Anti-Matter Created By Laser At Livermore

zootropole alerts us to a press release issued today by Lawrence Livermore National Laboratory, announcing the production of 'billions of particles of anti-matter.' "Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear. The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.' This new ability to create a large number of positrons in a small laboratory opens the door to several fresh avenues of anti-matter research, including an understanding of the physics underlying various astrophysical phenomena such as black holes and gamma ray bursts." The press release doesn't characterize the laser used in this experiment, but it may have been this one.

Comments

Hey!

[Robin47]

Watch where you point that thing!

Re:Hey!

[MarkRose]

Don't lase me, bro!

Re:Hey!

[Iamthecheese]

Anti-matter particle beam... AMPB..nah.. Beam of Antimatter Particles! thats it! BAP

Re:Hey!

[DigitalHammer]

SHOOP DA WHOOP :P

Re:Hey!

[kauttapiste]

Do not look into the anti-matter beam with remaining eye!

Re:Hey!

[andrikos]

Tell that to the shark who has this laser mounted on his back

Re:Hey!

[aliquis]

Time until US military develop this into a weapon?

Re:Hey!

[flatcat]

I think it is this one it can smash anything!

Re:Hey!

[Lord Apathy]

Time until US military develop this into a weapon?

That is the first question that I though of. Is it cheaper to produce antimatter this way instead of the standard. With a large ass atom smasher. The air force has already stated that it is interested in a antimatter weapon.

Never fails to amaze me how stupid people can actually be. People don't realize how dangerous a antimatter bomb would be. Antimatter weapons are not like nukes. Nukes can't go off on their own. They require a trigger. A antimatter weapon can. Just the slightest change in energy level or failure in the containment.

Take the there types of weapons, fission, fusion, and annihilation. Named after their core detonation processes. And put them in a field with no maintenance. On their own the fission and fusion weapons will fail but will never go off. Eventually both bombs will be inert and completely harmless.

But the antimatter weapons will eventually go off 100% of the time when the containment eventuality fails. Messing with these weapons is simply fucking insane.

Re:Hey!

[Anonymous Coward]

Sounds just like Dynamite.

Re:Hey!

[hardburn]

Little Boy (droped on Hiroshima) converted 600 mg of matter into energy. For the same level of explosion of an anti-matter bomb, you'd need to create 300 mg of anti-matter (since it also annilates with 300 mg of regular matter). Also note that Little Boy was several orders of magnitude smaller in yield than modern bombs.

NASA estimates using 10 mg of anti-matter to get to Mars, at a cost of $250 million to make the stuff using bleeding edge techniques available in 2006. Assuming this new technique drops that by an order of magnitude, and the price scales linearly with the amount of anti-matter you want, then it'll cost (250 / 10) * 30 = $750 million for a Little Boy equivilent.

Conclusion: anti-matter bombs are not cost effective compared to nukes, and are unlikely to ever become so, unless we find a natural source of anti-matter.

Re:Hey!

[Lord Apathy]

Conclusion: anti-matter bombs are not cost effective compared to nukes, and are unlikely to ever become so, unless we find a natural source of anti-matter

Cost effectiveness and military thinking often do not go hand in hand. Bring up the Manhattan project, it cost just over 2 billion dollars in 1945 to develop the A-Bomb. That was a lot of freaking dough in 1945. Now one can argue that it would have been more cost effective to put that money in better aircraft and incendiary weapons and simply burn Japan to the ground. No, the army wanted its big bomb and got it.

Same thing applies to antimatter weapons. That and there are other thing to think about with antimatter bombs. Their effectiveness and the ease at which they can be used. The smallest effective nuke, about 3kt, fits in a backpack and probably would weigh a 100 kg after shielding is added. Harder to sneak something like that past a border guard. With out the shielding it would be smaller and lighter but then there is detection from radiation leakage.

A antimatter weapon of several times the destructive power would fit in a fedex envelope. Would require no radiation shielding. Deployment could be as simple as mailing it to a target. Now this is only possible if containment devices can be gotten that small. I'm sure they can because there is no law of physics stating they can't. There is a law of physics stating how small a nuke can be.

Of course you don't have to ship a nuke in, in a backpack. You just shoot it from a missile or drop it from a plane. But all these methods can be detected and traced back to the source. Plane and missile have to come from somewhere.

There are many benefits to antimatter weapons to the right parties would offset their costs. One more thing your assuming that we can't come up with a cheap way to make antimatter. The same assumptions where made about the atomic bomb back before 1945. We know how wrong those where.

Re:Hey!

[Anonymous Coward]

Such a waste of materia to, we need it (especially if said materia happen to be a human.) /aliquis

I could say that this should go the same way as biological and chemical weapons, but then wars retarded in each and every way so that seems unnecessary.

Re:Hey!

[aliquis]

Conclusion: anti-matter bombs are not cost effective compared to nukes, and are unlikely to ever become so, unless we find a natural source of anti-matter.

He's probably in this thread already but what you're asking for seems to be: Nibbler.

Re:Hey!

[danieltdp]

So now sharks with frikin lasers can create antimatter? We are all doomed!

Re:Hey!

[Lord Apathy]

Just to set the record straight Nibbler shits DarkMatter, not Antimatter. WTF the difference is in this case I have no clue.

Re:Hey!

[mog007]

The Air Force has expressed interest in antimatter weapons for years, but if they've made any progress in the field, they're being quiet about it.

Re:Hey!

[Anaerin]

A antimatter weapon of several times the destructive power would fit in a fedex envelope. Would require no radiation shielding. Deployment could be as simple as mailing it to a target. Now this is only possible if containment devices can be gotten that small. I'm sure they can because there is no law of physics stating they can't.

Okay, considering that a single atom of the air (Or, indeed, the FedEx envelope you want to send this antimatter in) would be enough to start an annihilative reaction, you would have to be VERY certain of your containment system.

Such a containment system would need to have:

• A perfect vacuum, to remove the possibility of a random air atom colliding with your precious antimatter (Currently extremely difficult, if not impossible to manage)
• Some form of contactless barrier on the inside, to prevent the antimatter touching it's container (Anti-gravity and/or repulsor fields, then. Also currently virtually impossible within our atmosphere, let alone within a vacuum)
• Enough miniturisation to make all this fit in such a small area

And, to be honest, if you had that, you could apply the same technology to Uranium/Plutonium and ship a nuke via FedEx.

As they would say on Discovery Channel: Myth Busted.

Re:Hey!

[Anaerin]

Dark matter exists in our universe, is (as far as we know) totally nonreactive, but is massively dense, creating it's own gravitational field (So much so, it can affect the light coming from distant galaxies in an effect known as "Gravitational lensing").

Anti-matter, on the other hand, is very reactionary, and will react with normal matter, annihilating both itself and the matter to create gamma radiation.

Re:Hey!

[aliquis]

Ah, ok, sorry. Since it's used as energy source for their space ship I thought it was anti-matter (but if it was maybe his litter box would seize existing after a while.)

It's indeed dark, even black, in the series :)

I wonder what the benefit of using dark matter is, whatever dark matter happen to be. Or well, we already know it's Nibbler poop, but except that?

Does this mean

[sleeponthemic]

That the true enterprise of the future will have a "Shark Drive"?

Re:Does this mean

[SQLGuru]

I for one welcome our shark overlords with anti-matter rays strapped to their head?

Layne

Re:Does this mean

[Anonymous Coward]

LOL sharks LOL

Holy Mackerel!

[AKAImBatman]

Does anyone know how much energy this takes? They mentioned the previous petawatt laser experiment that was decommissioned, but I didn't see where it mentioend the power required for this experiment. If the laser guess by kdawson is correct, we could be looking at a mere 400 joules per 1E11 positrons. Which (if I'm not mistaken) would be an unheard of efficiency for creating antimatter! (Can someone verify? My brain is fried at the moment.)

What I find interesting is that this level of production is competitive with Fermilab. Even if they ran this twice an hour, they'd handily meet or outstrip Fermilab production.

Even more interesting is the possibility for mass manufacture of antimatter. By using mass-produced gold targets, you could rotate the materials in and out of the machine every few seconds, creating previously unseen amounts of antimatter. Such a process could easily provide materials for an antimatter catalyzed fission drive. Possibly even enough to power new forms of interplanetary propulsion.

Am I the only one who's getting really excited about this? /dreamer

Re:Holy Mackerel!

[theheadlessrabbit]

...Such a process could easily provide materials for an antimatter catalyzed fission drive. Possibly even enough to power new forms of interplanetary propulsion...

Am I the only one who's getting really excited about this?

probably. they still haven't been able to crystallize di-lithium yet.

Re:Holy Mackerel!

[FlyByPC]

Even more interesting is the possibility for mass manufacture of antimatter. By using mass-produced gold targets, you could rotate the materials in and out of the machine every few seconds, creating previously unseen amounts of antimatter.

If true, this is the 1940s all over again -- only on a larger scale. A thimbleful of antimatter would make any H-bomb look like a popgun. (...and yeah, I know we're not yet talking about anywhere near that order of magnitude. Yet.) It would certainly help with space exploration -- but we humans can't even be completely trusted with gunpowder and jet airplanes yet. *sigh*

Re:Holy Mackerel!

[Anonymous Coward]

Thermodynamics at work. Converting matter to antimatter and then into energy will take more energy than was released. Unless there is some kind of 'catalyst' that lowers the input energy requirements.

Re:Holy Mackerel!

[magarity]

Possibly even enough to power new forms of interplanetary propulsion
 
Yeah, because NASA (and similar agencies around the world) have whopping piles of cash laying around for this.
 
Reporter: What's it like to fly the new spaceship?
Pilot: Like burning a load of gold as fast as I can!
 
Yeah, and you think the class warfare rhetoric between the rich and poor nations is bad now?!?

Re:Holy Mackerel!

[Anonymous Coward]

By itself, that many positrons wouldn't provide anywhere near a net positive amount of energy. If you annihilated them all with electrons and managed to capture 100% of the resulting energy, you'd have 10**11 electron masses * c**2 ~= 0.016 Joules.

Sure, you could use the antimatter to fuel some other reaction as you suggested, but then again we already have fission reactors which produce net positive energy.

Re:Holy Mackerel!

[Joe The Dragon]

Just use a zpm to power it.

Re:Holy Mackerel!

[AKAImBatman]

Why is everyone so hung up on an energy-positive reaction? Antimatter is the ultimate in fuel for space-propulsion as it produces the highest theoretical amount of energy for the least possible mass. (i.e. 100% conversion - losses to nuetrinos that cannot be captured) This plays well into the rocket formula, giving antimatter drives a specific impulse unattainable with other rocket methodologies. In fact, the far-flung future may see c-ships traveling the stars based on matter-antimatter drives.

What I want verified is not if this process is energy efficient or not. I want to know if this process is several orders of magnitude more efficient than the current Fermilab and CERN processes.

Sure, you could use the antimatter to fuel some other reaction as you suggested, but then again we already have fission reactors which produce net positive energy.

Once again, antimatter catalyzation makes the fuel more efficient for its weight and thus plays well into the rocket formula.

Re:Holy Mackerel!

[AKAImBatman]

Yeah, because NASA (and similar agencies around the world) have whopping piles of cash laying around for this.

Yeah, research dollars would never fund anything like that. Except when they do.

Is it really so hard to click through the links? :-/

FWIW, there are quite a few antimatter engines on the drawing board. They're only missing one key component: Antimatter. And this new technology may be the key to providing it in spades. (Relatively speaking, of course.)

Re:Holy Mackerel!

[frieko]

Bah!! We can't trust NASA to burn our gold, there's special agencies for dealing with this sorta thing!

Re:Holy Mackerel!

[AKAImBatman]

If true, this is the 1940s all over again -- only on a larger scale

Not really. We've already done the whole Cold War/Mutually Assured Destruction thing. Our weapons are already far, far larger than we could ever deploy here on Earth. Making them that much bigger only makes them that much more useless. At best, the only real advantage would be that they could be scaled down.

Until we start looking at warfare on an interplanetary or interstellar scale, our existing nukes and possible antimatter warheads are going to sit in their silos and go unused. Or in the case of antimatter bombs, I simply hope they're not built. The idea of a large-scale antimatter warhead being prevented from detonation by mere magnetic fields maintained by the nearest power plant is not an appealing idea. Just disrupt the power infrastructure for long enough and we'll blow ourselves to kingdom come. :-/

Re:Holy Mackerel!

[zippthorne]

60e6*1e3 kcal / c^2= 2.8 kg of antimatter will give any H-bomb look like.. uh.. something that's the same size as an H-bomb. H-bombs have been proposed (and postulated to have been built) that are larger than 60 MT, and a pop-gun typically has only a few Joules, so you'd need many orders of magnitude more than 2 kg of antimatter to make an H-bomb look like a pop-gun. something like.. four times the mass of mount Everest, in antimatter.

Re:Holy Mackerel!

[Kagura]

Does anyone know how much energy this takes? They mentioned the previous petawatt laser experiment that was decommissioned, but I didn't see where it mentioend the power required for this experiment.

The great thing about this for spaceflight isn't that it takes a lot or a little to produce antimatter, but rather that the density of usable energy is orders upon orders of magnitude greater than chemical or electric rockets. Denser energy leads to more fuel carried leads to greater delta v leads to semi-relativist flight leads to hate leads to suffering. These can even be used within the atmosphere to launch rockets from the ground easier than you can say "prompt gamma ray output".

Re:Holy Mackerel!

[Boronx]

Until we start looking at warfare on an interplanetary or interstellar scale, our existing nukes and possible antimatter warheads are going to sit in their silos and go unused.

Nukes have already been used, and do to dangerous attitudes like yours, which seem to proliferate as more time passes since the last use, they are likely to be used again.

Re:Holy Mackerel!

[Kagura]

There's nothing wrong with your post--I'm just pointing out that it's still not close to 100% conversion:

Not all of that energy can be utilized by any realistic technology, because as much as 50% of energy produced in reactions between nucleons and antinucleons is carried away by neutrinos, so, for all intents and purposes, it can be considered lost.

Re:Holy Mackerel!

[techno-vampire]

It's even worse than that. During a panel at LACon II, back in '84, Dr. Robert Forward said that according to the best calculations, if you dropped a lump of anti-matter on the floor, it wouldn't vanish in a flash of gamma rays, it would sizzle like a drop of water on a hot griddle. You see, the anti-matter can only interact with its environment and annihilate on its surface, and there's this little thing called the "cube-square law" that says that very little of it is going to be on the surface.

Re:Holy Mackerel!

[Klaus_1250]

(60e6 * 1e3 kcal) / (c^2) = 2.7931967 grams. That is about a factor 1000 less.

The largest H-bomb ever build/detonated, the russian Tsar Bomb, was about 50MT, but capable of 100MT. I never heard of anything larger, but is/was there?

Re:Holy Mackerel!

[AKAImBatman]

Nukes have already been used

Yeah, once. (Twice if you want to be pedantic.) Then never again. The whole point was that the display of force showed that the weapons were too dangerous to use. As long as the various sides have them pointed at each other, no one dares use them.

The only reason why the Cold War was so terrible was that the USA and the USSR were both waiting for the other to attack. Since neither one liked each other much (for both idealogical and practical reasons) the chance that an armed conflict would happen between the two powers was pretty darn high. Except that an armed conflict might precipitate into a nuclear war should either side feel backed into a corner.

Thus the reason why the US didn't win Vietnam. The chance of starting a nuclear war was too great to risk pressing the war to a conclusion. Which raised the (very legitimate) question of why we were even in the conflict to begin with.

Re:Holy Mackerel!

[AKAImBatman]

That would probably be why I said, "i.e. 100% conversion - losses to nuetrinos that cannot be captured". Apologies for mixing in the minus sign rather than spelling it out. As I mentioned previously, it's late and my frain is bried. ;-)

Re:Holy Mackerel!

[ravenshrike]

Bzzt, wrong. Converting M into AM takes a certain amount of energy which may or may not be(probably is) less than the energy released by a M/AM annihilation event.

Re:Holy Mackerel!

[Rayban]

What would happen if you aerosolized said cube with a small explosive?

Re:Holy Mackerel!

[Anonymous Coward]

We already have fission reactors which produce net positive energy, so there is no need to research any alternative energy source?

Re:Holy Mackerel!

[Ann Coulter]

It should be (60e6 * 1e3 kcal) / (2*c^2) = 1.39659835 since the normal matter that will also be annihilated will contribute to the mass-energy conversion.

Re:Holy Mackerel!

[Hal_Porter]

A thimbleful of antimatter would make any H-bomb look like a popgun.

A popgun. You see? You see? Your stupid minds! Stupid! Stupid!

Re:Holy Mackerel!

[Quantum Jim]

I don't think this compares with Fermilab. The fine article is talking about creating positrons, not anti-protons. This isn't the first time I've heard about creating positrons from a laser shown upon a gold foil target. Here are two (from 2004 and 2001 respectively) that I just found on Google Scholar describing a result and a theory behind the positron production:

http://llacolen.ciencias.uchile.cl/~vmunoz/download/papers/wclpp05.pdf
http://www-project.slac.stanford.edu/lc/local/PolarizedPositrons/doc/ClassicalPapers/B_Shen-J_Meyer-ter-Vehn-PRE65_16405.pdf

It also isn't very efficient. They make 10^11 positrons per 400 J of energy input. If those positrons react with 10^11 electrons, they produce gamma rays with the energy 2 * (electron mass * (10^11)) * (c^2) = 0.0163742083 joules. Maybe it is more efficient than Fermilab, but that's still not very much. Since these are light positrons - not heavy anti-protons - I don't think these results would be very useful for fusion. Maybe as a source of gamma rays or as a research tool.

Re:Holy Mackerel!

[Thanshin]

Indeed, the manufacture of antimatter bombs would most certainly accelerate space exploration.

Re:Holy Mackerel!

[AKAImBatman]

Thank you sir, you are my hero. (Even if you did just burst my balloon. :-P) Now I'm off to get some rest. By morning all the math should make sense again and I'm sure I'll be kicking myself with a "why didn't I see that?"

Thanks again! It really is appreciated. :-)

Re:Holy Mackerel!

[techno-vampire]

Good question. I presume that the reaction would be somewhat more energetic, but nobody thought to ask, and he didn't say.

Re:Holy Mackerel!

[lysergic.acid]

that's a pretty interesting concept. it seems very far-fetched, but they've obviously put a lot of thought into the technical and logistical problems such a ship would face. here's an excerpt of my favorite part:

Shield
Our ship is icy-white in colour for the very excellent reason that its exterior is made of water ice, one of the most abundant substances in the universe. When we travel at extreme velocities, dust particles impact our ship with the energy of a nuclear bomb, and even hydrogen atoms erode her hull. Before embarking on a mission, we re-make the surface of the ship with ice harvested from the abundant comets surrounding the star we're departing. During the mission, self-reproducing robots built with molecular-scale engineering repair damage to the ice shield around our ship. The ice protects us against impacts with interstellar and intergalactic gas and tiny dust particles. If we hit something of tangible size, like a rock, it'll be a really bad day; astronomers on distant planets will catalogue yet another enigmatic gamma ray burst.

hopefully by then we'll have invented deflector shields and inertial dampeners (so that humans can ride on such ships without being liquefied).

Re:Holy Mackerel!

[shma]

If true, this is the 1940s all over again -- only on a larger scale.

Calm down. The energy released by annihilating 100 billion positrons doesn't even come to 10 millijoules. Let me put it another way. According to Wikipedia, 0.6 g of matter was transformed into energy in the first uranium bomb explosion. This amount of anti-matter weighs 10^-16 g. That's 16 orders of magnitude less energy released. On top of that, there's no way to contain antimatter for long periods of time, so there's no way to gather enough anti-matter to make a bomb. But even if that technology were discovered tomorrow, and we could produce this much anti-matter every second, it would take a billion years to get enough anti-matter to make a bomb as powerful as only the first atom bomb. Feel better?

Re:Holy Mackerel!

[techno-vampire]

Nuclear devices in the megatons have only been deployed and detonated in a theater of openly declared war twice.

If you're referring to Hiroshima and Nagasaki, you're wrong. Both of those devices were in the kilotons, not megatons.

Re:Holy Mackerel!

[Boronx]

The only reason why the Cold War was so terrible was that the USA and the USSR were both waiting for the other to attack. Since neither one liked each other much (for both idealogical and practical reasons) the chance that an armed conflict would happen between the two powers was pretty darn high. Except that an armed conflict might precipitate into a nuclear war should either side feel backed into a corner.

You are misinformed about how close and how often the US and USSR came to nuclear exchange, and at the very real strategic possibility that first strike was the safest option, and at the political strength of it's proponents. This is beside the near-missed accidental launches that happened on both sides several times.

You probably are also not aware of how far the nuclear situation has deteriorated since the end of the cold war.

Your Panglossian view of Nukes and MAD, which is probably representative of a broad swath of people who would rather not think about this world of terror, will lead us right towards nuclear war.

Thus the reason why the US didn't win Vietnam. The chance of starting a nuclear war was too great to risk pressing the war to a conclusion. Which raised the (very legitimate) question of why we were even in the conflict to begin with.

Where the hell did you get this idea? What could we possibly have done to Vietnam that would have caused a nuclear attack from the communists? If we'd turned Vietnam into glass ourselves, a long shot but maybe. Even so, that outcome even without retaliation would have been much worse than the one we got.

Re:Holy Mackerel!

[alxkit]

is it the same NASA that does not have whopping piles of cash laying around to do urine degustation?

Re:Holy Mackerel!

[Hal_Porter]

That page on c ships is fascinating

    Alpha Centauri 4.36 ly 268 days 0.999128 4.56 years
          Sirius 8.64 ly 314 days 0.999769 8.84 years
          Polaris 783 ly 1.71 years 0.999999997 783.4 years

Is it me or is 8.84 years not a bad deal for a trip to Sirius?

I suspect if you had the technology to make the antimatter, some sort of suspended animation would be well within your capabilities too given current advances in molecular biology. And given time you could colonise the galaxy slowly but surely in series of short (<20ly) hops from star to star.

Re:Holy Mackerel!

[AKAImBatman]

We learned an invaluable lesson out of Vietnam. We learned that the Cold War was not going to be won on military might. Which eventually lead to the solution of bankrupting the USSR. (Something which would have eventually happened anyway, just much slower.) The part that hurts is that we learned the lesson at the cost of millions of lives. At that high of a price, we may as well have dropped a nuclear bomb.

Don't get me wrong. I do not have a particular position on the war. In fact, many South Vietnamese are very grateful for the work our troops did over there. But in the 20/20 hindsight of history, we can see what an incredible price the Cold War exacted. The desire not to return to such horrors is a strong incentive for the world to never fire their nuclear arsenals in anger.

Of course, there is the sticking point of Iran. There's a good chance a LOT of people in the Middle East could die should Iran gain nuclear weapons and decide to use them regionally. There's a fair likelihood that Iran would be glassed over in retribution, but the damage will have already been done. With a little luck and a lot of prayer, MAD will ensure that Iran never fires her weapons.

Re:Holy Mackerel!

[Anonymous Coward]

Anti matter bombs are not very practical because they require quite large amounts of anti-matter -- and more anti-matter you have the harder it is to contain.

So the containing is the problem. Atomic weapons are quite small and easy to store for a long time. Anti-matter bombs leak constantly because of quantum effects.

Re:Holy Mackerel!

[Alex Belits]

Which eventually lead to the solution of bankrupting the USSR. (Something which would have eventually happened anyway, just much slower.)

Or, to be exact, it didn't happen.

Re:Holy Mackerel!

[linzeal]

The US military has already started demanding one. Which means some other country has a program as well, my bet is Russia. The only peaceful use for such power that I can conceive of would be to restart the core of a planet like Mars to give it a magnetic field.

Re:Holy Mackerel!

[Kagura]

Well, in my mind 50% loss is quite a lot, but I said there's really nothing fundamentally wrong with your post. Just thought it was an interesting enough fact. ;)

Re:Holy Mackerel!

[iamapizza]

A thimbleful of antimatter would make any H-bomb look like a popgun.

It'll give new meaning to the term "pin drop silence".

Re:Holy Mackerel!

[Pr0xY]

I believe you are mistaken. Everything I've hear suggests that a teaspoon of the stuff could level a city.

Re:Holy Mackerel!

[Anonymous Coward]

Presumably, since this is using lasers, the gold is somehow focusing the photons and increasing the probability that the photons decay to electron positron pairs. But then again I haven't had a particle physics class so this is wild speculation. As far as I know positrons are only made through nuclear decay or photons spontaneously turning into an electron positron pair.

Re:Holy Mackerel!

[Pr0xY]

except that anti-matter/matter collisions have a FAR more efficient conversion to energy so you need much less of it.

Re:Holy Mackerel!

[CarpetShark]

Our weapons are already far, far larger than we could ever deploy here on Earth. Making them that much bigger only makes them that much more useless.

One could argue that all wars are worse than useless. Doesn't stop them happening. In fact, the US Air Force has already shown interest in anti-matter weapons:

http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2004/10/04/MNGM393GPK1.DTL

http://en.wikipedia.org/wiki/Antimatter_weapon

Re:Holy Mackerel!

[Anonymous Coward]

H-bombs have been proposed (and postulated to have been built) that are larger than 60 MT, and a pop-gun typically has only a few Joules, so you'd need many orders of magnitude more than 2 kg of antimatter to make an H-bomb look like a pop-gun.

Where are the "-1, irritating fucking pedantry" and "-1, unable to understand a figure of speech" moderation options?

Re:Holy Mackerel!

[Anonymous Coward]

Is it me or is 8.84 years not a bad deal for a trip to Sirius?

That depends on whether you can get a good deal on a billion tons of sunscreen too.

Re:Holy Mackerel!

[Whiteox]

It wasn't a war, it was a police action.

Re:Holy Mackerel!

[skavenger]

Pedantic? Really?

To say nukes were only used once or twice is terribly misleading. Nukes were only used in a military capacity twice. Even more accurately, they were only used in a military capacity against strategic targets twice. They've been used for political posturing and military advancement approximately 2,000 times in various settings and with varied payloads.

This isn't intended to devalue the magnitude of the decision to effectively annihilate large numbers of human populations or suggest that testing is necessarily equivalent, just to remind you that the tactical application of nuclear weapons is not the only undesirable consequence of developing, distributing, and maintaining those weapons. Even unused nukes have serious consequences to the well being of humans and ecosystems in general.

The display of force in Hiroshima and Nagasaki demonstrated that the weapons were too morally reprehensible to use against human targets. The militarization of the United States and other nations has prevented critical assessment of the relative danger of these weapons from being reflected in policy until fairly recently. Check the graph on that wiki. Does it seem as if people suddenly became aware of the danger of nukes in 1945, or merely their effectiveness? And I'm not even getting into the tailings piles, superfund sites, government payouts to victims of testing, and so on.

Pedantic? Try having a complete thought before accusing someone of pedantry. There are more things going on here than the dramatic end of people's lives or your fantasies about interstellar warfare.

Re:Holy Mackerel!

[Whiteox]

You've got to accelerate and slow down.

Accelerating at 1g to close to the speed of light then slowing down at 1g to be able to orbit the planet does take time as well. Probably double time for the trip to Alpha Centauri. I don't have the math to work it out though.

Re:Holy Mackerel!

[EdIII]

the whole Cold War/Mutually Assured Destruction thing

That ONLY applies to large countries like China and Russia. The powers that be in those countries have just as much to lose as we do. Cooler heads have always prevailed and those weapons just sit unused for decades.

What you are not taking into account is unstable governments that possess nuclear capabilities like North Korea and Pakistan (possibly Iran in the future). I would even include India in that statement since they just might be crazy enough to attack Pakistan if suitably provoked. After all, it's just a huge religious conflict with those governments and their people when you get right down to it. North Korea excluded of course as it seems to be at war ideologically with the rest of the planet entirely.

The greatest threat is terrorist organizations such as Al-Q. They are such religious zealots and possess unwavering faith that they will be rewarded in heaven for the destruction of the infidels on Earth. If any one of those terrorists organizations got a hold of nuclear material it is NOT a question of if they use it, but when and what target. Al-Q with anti-matter weapons? Kiss most of the civilized world good bye.

The effect of M.A.D as a deterrent is proportional to the size and sophistication of the groups of people that possess such technology. M.A.D works the most effectively on superpowers and the least effectively on depressed homicidal maniacs that just want enough people to feel their pain as they die.

People as a whole cannot be trusted with any kind of weapons. Every day someplace on this planet somebody is killing a bunch of other people with a weapon. Sometimes with a reason, other times just because they are mentally unstable. With a few notable exceptions, those weapons have a limited effect. A couple of guys with automatic weapons could kill a couple dozen people before being taken out by law enforcement. One determined group of people can take out hundreds of people with enough explosives like the Hilton in Pakistan recently.

One guy with an anti-matter weapon can destroy the whole planet. As the availability of anti-matter technology to people rises towards 100% so does the chance of us annihilating ourselves.

Maybe the future will be as idealistic and Utopian as Star Trek. I hope so. However, you get even one mentally unstable screwball with very high levels of technology and the body counts start rising orders at a time.

Re:Holy Mackerel!

[davedx]

It's creating positrons - you can't fuel a spaceship with positrons.

Re:Holy Mackerel!

[EdIII]

hopefully by then we'll have invented deflector shields and inertial dampeners (so that humans can ride on such ships without being liquefied).

Don't forget the Holodeck. Intergalatic trips without it might as well just be a mobile prison. Do you remember cross country trips with your parents or grand parents? Multiply that, by like a million or something.

Re:Holy Mackerel!

[ion.simon.c]

Anti-matter bombs leak constantly because of quantum effects.

Cite?
I didn't know that antimatter bombs existed. OTOH, I'm an ignorant fucker, so perhaps it's not surprising. ;)

Re:Holy Mackerel!

[ion.simon.c]

Verily, this is -at present- the best thread attached to this article!

Re:Holy Mackerel!

[ion.simon.c]

OT: More people need to take your .sig to heart. Seriously. : D

Re:Holy Mackerel!

[Kirth Gersen]

AKAImBatman (238306):

the only real advantage would be that they could be scaled down.

Excellent point. Back in the 80s people were muttering about "suitcase nukes", though for some reason that quieted down -- maybe Sandia never got the funding.

With significant amounts of antimatter -- like about 10**12 times as much as discussed in the article -- and a good containment system, you could make a bomb the size of a pencil eraser that would take out the Pentagon. Not that there's anything wrong with that.

Re:Holy Mackerel!

[Johnno74]

Antimatter weighs the same as normal matter.

Yep, about .6g of matter was converted to energy by little boy. That means the same energy would be released as .3g of matter meeting .3g of antimatter.

Not sure where you got 10^-16g.

Yes antimatter is powerful. But not by that many more orders of magnitude.

Re:Holy Mackerel!

[Anonymous Coward]

Am I the only one who's getting really excited about this? /dreamer

Yes, Sheldon

Re:Holy Mackerel!

[OrangeTide]

Reposting links to ill informed posts you made doesn't make your armchair evaluation of the politio-economic situation any more correct.

Re:Holy Mackerel!

[mr_gorkajuice]

Well, it all depends. I don't know much about the density of antimatter, and the explosive power depends on mass, not volume. Though, considering how rare antimatter is and how difficult it is to work with, one could very well say that a teaspoon of antimatter is a LOT of antimatter. Everything's relative, y'know. And speaking of relativity, E = mcc is the key to figuring the explosive power, as this describes the mass-to-energy convertion rate.

Let's say there's 5 grams of antimatter in a teaspoon.
E = 0.005 kg * 300000 m/s * 300000 m/s = 1350000000 J = 1.35 GJ
For comparison, the explosive force of one ton of TNT is 4.18 GJ, so yeah - roughly speaking, 15-20 grams of antimatter equals one ton of TNT.
However, I have no clue how much TNT it takes to level a city.

Re:Holy Mackerel!

[bytesex]

Vietnam was a tie !

Ok. So go see 'a fish called Wanda'.

Re:Holy Mackerel!

[Bizzeh]

i assume 1.21 jiggawatts

Re:Holy Mackerel!

[Candid88]

I've always thought the Cold War was more of a media thing than anything else. Warning about an imminent threat of nuclear war is obviously a darn good way of getting people to buy your newspaper or watch your TV news program - and not to mention getting people to vote for you (and conversely, telling people not to panic is nearly always a big vote loser).

In reality, there were some disagreements and various localized conflicts (predominantly in 3rd world countries, just like we have today) but compared to the landscape leading up to the first two world wars, it was all (comparatively) pretty trivial stuff really.

Re:Holy Mackerel!

[Davidis]

anti matter reacts with matter. inorder to store antimatter it needs to be seperated from its matter counterpart. This takes energy. Because at the molecular level antimatter is quite unstable (the reason we dont alot of it) we cannot be 100% certain that there is no matter inside the container. or that a subatomic particle of matter will not enter it. at the moment there are no KNOWN antimatter bombs. but to put this into perspective in 1940s there were no KNOWN nuclear bombs until after nagasaki and hiroshima. by known i mean outside of the military and associated trades. (official secrets act?)

Re:Holy Mackerel!

[JohnFluxx]

I did the calculations for an earlier post:

If you accelerate at 9.8m/s^2 for half the journey and -9.8m/s^2 for the second half of the journey (so that it's just like earth's gravity) then you would arrive at the planet after:

1.94 arccosh(n/1.94 + 1) years

For n=10.5 light years, this gives 4.9 years.

For other values of distance:
4.3 ly nearest star 3.6 years
27 ly Vega 6.6 years
30,000 ly Center of our galaxy 20 years
2,000,000 ly Andromeda galaxy 28 years

(For distances bigger than about a thousand million light years, the formulas given here is inadequate because the universe is expanding. General Relativity would have to be used to work out those cases.)

So for someone in the rocket, they could arrive at the planet in 4.9 years.

If you had an 100% efficient engine (using anti-matter/matter), the fuel required would be:

d Stopping at: M
4.3 ly Nearest star 38 kg
27 ly Vega 886 kg
30,000 ly Center of our galaxy 955,000 tonnes
2,000,000 ly Andromeda galaxy 4.2 thousand million tonnes

I find it fascinating that within a human lifetime (for the people in the rocket) we could travel to another galaxy.

(I'm a theoretical particle physicist)

Re:Holy Mackerel!

[savuporo]

It was also horribly impractical and ineffective. Large yield nuclear weapons are now normally regarded superseded by MIRV-type warheads.

Re:Holy Mackerel!

[Davidis]

NEVER AGAIN now where have i heard that before. WW1 WW2 every war since. I take it your not a student of history. After world war 1 over 90 years ago now. every country was adamant that war on that scale w2ould never happen again. After world war 2 and the atrocities commited by the NAZI regime in the holocaust every country was adamant that a genocide would never happen again. Ok now since ww1 there ahs been other wars where trench fighting and guns are still used and the death toll is similar. after ww2 there has been other genocides. So BS america or another big headed arogant nation will use nukes again on an offensive scale. MAD will follow the like of the league of nations, nato and the un will be as powerless as iraq has shown them to be. ANd yes they are as otherwise how can you explain how a group of hundreds of nations with large navies cannot even stop the pricay happening to trade ships around somalia. (a country on the eastern coast of africa(a continent south of europpe))

Re:Holy Mackerel!

[Anonymous Coward]

You seem to be ignoring Israel already having nuclear weapons. And considering past behaviour, they're more likely to pull off a nuclear first strike than Iran would, should the latter ever get nuclear weapons.

Re:Holy Mackerel!

[Davidis]

actually hes right. in any reaction energy is lost. If this matter to antimatter is a endothermic reaction then you need to take into account the energy being entered. This will be less than the resulting energy but as the matter being used in the final event is created elsewhere with its own energy then the rules do not apply as we are not using a closed system or analysing all the data. by the rules of thermodynamics there is always energy loss but with antimatter half the energy and mass of the bomb is the target itself.

Re:Holy Mackerel!

[vikstar]

Why is everyone so hung up on an energy-positive reaction? Antimatter is the ultimate in fuel for space-propulsion

Why is everyone so hung up on space-propulsion? Anything that you put a battery or fuel into will run almost forever.

Re:Holy Mackerel!

[Alex Belits]

I was there, you moron.

Re:Holy Mackerel!

[ion.simon.c]

So, to summarize:

Basic Physics lesson.
State Secrets, so we can't be sure.

Thanks. :)

Re:Holy Mackerel!

[Gromius]

Just a small point: positrons!=anti protons, so this isnt beating fermilab just yet :)

Positrons are pretty easy to make as they are a fundamental object and are readily produced by photons. In fact as a high energy photon hits matter, it will pair convert into an electron-positron pair. So to make a positron you just need a big laser :)

Anti-protons are very difficult because you need to produce 2 anti up quarks and one anti down in a pound state. Thats as tricky as it sounds. In practice you just bash a stream of protons into a target and hope for the best. Hence the rather low efficiency.

Re:Holy Mackerel!

[Kagura]

Hmm, as I recall they were 0.013 and 0.021 megatons for Hiroshima and Nagasaki, respectively. ;)

Also, when you write it this way, it makes the impact of "20 megaton" nuclear bombs a lot more powerful. Pin not indented.

Re:Holy Mackerel!

[Kagura]

at the moment there are no KNOWN antimatter bombs. but to put this into perspective in 1940s there were no KNOWN nuclear bombs until after nagasaki and hiroshima. by known i mean outside of the military and associated trades. (official secrets act?)

There's also no KNOWN lost Ark of the Covenant or photon torpedoes or earthquake/weather control devices in government possession. By known, I mean outside of military and associated trades. (Official Secrets Act?)

Re:Holy Mackerel!

[locofungus]

It's even worse than that. During a panel at LACon II, back in '84, Dr. Robert Forward said that according to the best calculations, if you dropped a lump of anti-matter on the floor, it wouldn't vanish in a flash of gamma rays, it would sizzle like a drop of water on a hot griddle. You see, the anti-matter can only interact with its environment and annihilate on its surface, and there's this little thing called the "cube-square law" that says that very little of it is going to be on the surface.

I disagree. If we're talking about macroscopic sizes (say a gram or two) then while initially the reaction might be "slow" the heat is going to very quickly vaporize the antimatter (and the floor it's resting on) and you're going to get a dramatically increased reaction speed.

Plutonium-238 will vaporize itself if you collect a large enough lump of it in one place and Pu-238 is a positively gentle decay compared to matter-antimatter annihilation.

One of the significant engineering problems for building a nuclear bomb is keeping the device together for long enough for there to be significant fission (and fusion where appropriate) taking place. A lump of antimatter wouldn't have that issue - even if it took a tenth of a second to annihilate rather than a few nanoseconds of fission in a bomb it's still going to be pretty catastrophic.

Tim.

Re:Holy Mackerel!

[Kagura]

Satchel nukes and devices that fit within safely firable artillery shells or were hand-portable were manufactured in usable quantities. Some key bridges in Germany were even designed to be destroyed by man-portable nukes that would be emplaced upon full-scale war.

"Suitcase nukes" are just a hip and a skop away.

Re:Holy Mackerel!

[Anonymous Coward]

What the hell else could he be referring to?

Re:Holy Mackerel!

[ultranova]

One guy with an anti-matter weapon can destroy the whole planet. As the availability of anti-matter technology to people rises towards 100% so does the chance of us annihilating ourselves.

Okay, hold it there. This experiment - and all conceivable ones - uses energy-to-matter conversion to create the antimatter. Since energy is converted equally to both matter and antimatter, the theoretical best efficiency of this process is 50%. When antimatter annihilates with matter, it is converted back to energy along with matter, so it releases 200% of its mass in energy. In other words, assuming perfect processes either way, antimatter creation plant acts like an extremely high-capacity battery.

In other words, in order to destroy the world with an antimatter bomb, you first have to produce this energy some other way and store it as antimatter. Hoover Dam produces 2080 megawats, according to Wikipedia, which means 2,080,000,000 Joules/sec. Also according to Wikipedia, a megaton of TNT is equivalent to 4.184×10^15 Joules. This means that it would take about 23 days to produce enough antimatter for a single megaton explosion using all the power produced by the Hoover Dam for this project.

Or, to put it even simpler: to get even nuclear-level antimatter weapons, you need to have nuclear power plants or equivalent to begin with, so why not simply make conventinal nukes ? It's less conspicious and they're less likely to blow up on your own face.

So please stop fear-mongering. It's done us enough harm and killed enough people already by stalling the sprea of nuclear power plants, thus forcing the use of fossil fuel plants to meet our energy needs with all the associated nasty poisonous and mildly radiactive smoke they spill into the air. Mad scientists trying to blow up the world belong to sc-fi stories and have nothing to do with reality.

Re:Holy Mackerel!

[Tony Hoyle]

Judging by Hiroshima, it's in the kiloton range.

Re:Holy Mackerel!

[marcosdumay]

"but we humans can't even be completely trusted with gunpowder and jet airplanes yet."

I dunno... We already have enough power to destroy most of the Biosphere, improving that power to destroy the entire planet can not be much worse.

Re:Holy Mackerel!

[sdpuppy]

There's also no KNOWN lost Ark of the Covenant or photon torpedoes or earthquake/weather control devices in government possession. By known, I mean outside of military and associated trades. (Official Secrets Act?)

Excellent!

BTW, you forgot aliens - there are no aliens either.

{quickly pushes antenna back into head}

Re:Holy Mackerel!

[192939495969798999]

Livermore has some seriously big lasers, including a 750 Terawatt number that creates tiny, short-lived "sun's". Don't point that one in your eye!

https://www.llnl.gov/str/Remington.html

Re:Holy Mackerel!

[dafradu]

If true, this is the 1940s all over again -- only on a larger scale.

I prefer my weapons of mass destruction to be big fat size of a house rockets then something you can carry around on your keychain.

Re:Holy Mackerel!

[sdpuppy]

That assumes that your antimatter is in convenient handy dandy molecular form. If your antimatter is in the form of a bunch of anti-electrons in some containment system which is opened, they'll shoot out faster than a bunch of slashdotters set loose in a computer convention. They will disperse rapidly.

Re:Holy Mackerel!

[Anonymous Coward]

This appeals to the mad scientist in me. Just an ounce of this stuff is enough to create a bomb equivalent to one Megaton TNT. But the best part is there is no critical mass. This means bombs can be scaled down to create beautiful beautiful weapon systems. e.g. a toy airplane sized UAV could carry thousands of milligram sized bomblets each with the explosive force of a 1000 pounder. One such UAV would have more firepower than the Shock and Awe that was unleashed on Bagdad in the first Gulf War! e.g. a small sattelite in low earth orbit could lay waste to the entire US of A by launching thousands of ball bearing sized bomblets into the atmosphere. They would be completely undetectable by radar and reach their targets in seconds. e.g. a sharpshooter armed with bullets containing tiny anti-matter bombs could destroy an entire tank brigade and a fleet of helicopters before they even knew what hit them. It is not only wise to develop this technology before our enemies do so (and they will), it is our duty!

Re:Holy Mackerel!

[oodaloop]

Al Qaeda has been trying to build a nuclear device for some time now, and they certainly have no compunction against setting off a nuclear war. If they could get their hands on an anti-matter bomb that could blow up North America, they'd set it off in a heartbeat. I'm sure there are other weirdo groups that would love to start the apocalypse too.

Re:Holy Mackerel!

[Anonymous Coward]

"but we humans can't even be completely trusted with gunpowder and jet airplanes yet. *sigh*"

Hey, never mind that crap...we can't even be trusted to reliably manage beer and tricycles.

Yet.

Re:Holy Mackerel!

[mevets]

Aren't they already doing this? I saw a documentary once that featured a huge spaceship powered by it.

Re:Holy Mackerel!

[NatasRevol]

Twice?

For the record, we've dropped nuclear bombs on four countries.

Japan, Spain, US, Greenland.

Not all of them were on purpose, but that doesn't mean they weren't dropped.

http://en.wikipedia.org/wiki/List_of_military_nuclear_accidents

Three of the four countries still have radioactive material on the ground from them. And they just couldn't find it in Greenland.

Re:Holy Mackerel!

[windsurfer619]

I love how you're right because if you're wrong, no one would be alive to say anything about it.

Re:Holy Mackerel!

[argStyopa]

Pretty much correct on the largest H-bomb, but not precisely so. Whether this matters is a question of your level of interest.

Largest bomb detonated was the 50mt Tsar bomba, by the Soviets (http://en.wikipedia.org/wiki/Tsar_bomb). It was actually scaled down from it's theoretical max yield by 50% due to concerns about fallout. Some speculate that the real consideration was that the pilots couldn't get away sufficiently to survive a 100mt blast.

" The fireball touched the ground, reached nearly as high as the altitude of the release plane (so a 10km/6-mile diameter fireball), and was seen and felt almost 1,000 km (621 miles) from ground zero. The heat from the explosion could have caused third degree burns 100 km (62 miles) away from ground zero. The subsequent mushroom cloud was about 64 km (40 miles) high (nearly seven times higher than Mount Everest) and 40 km (25 miles) wide. The explosion could be seen and felt in Finland, even breaking windows there.[7] Atmospheric focusing caused blast damage up to 1,000 km (621 mi) away. The seismic shock created by the detonation was measurable even on its third passage around the Earth.[8] Its Richter magnitude was about 5 to 5.25.[9]"

It was found to be ultimately inefficient as a weapon, except for the 1960's version of epeen.

Re:Holy Mackerel!

[Anonymous Coward]

This article talks about positron production (which are positively charged particles). Your Wikipedia article requires anti-protons, which are negatively charged. The rest mass of the proton (or anti-proton) is much larger than the electron/positron. An understanding of this experiment may lead eventually to a means of producing anti-protons, but this experiment as it stands is not going to be helpful in any fission reaction driven by anti-protons.

Re:Holy Mackerel!

[Anonymous Coward]

For n=10.5 light years, this gives 4.9 years.

am i missing something? how do you travel 10.5 lightyears in anything less than 10.5 years?

Re:Holy Mackerel!

[shma]

except that anti-matter/matter collisions have a FAR more efficient conversion to energy so you need much less of it.

I'm taking that into account. 64 kg of uranium was in the first atom bomb. 0.6 g of that was converted into energy. I'm assuming all of the antimatter produced here is converted into energy.

Re:Holy Mackerel!

[MikeBabcock]

Mutually assured destruction is undermined by weapons that can be deployed covertly.

If you could deploy weapons of mass destruction to the opposing 'force' without their knowledge, they would never get to hit the 'fire' button and they'd be dead without firing back.

Mutually assured destruction is only valid because both parties were launching nukes in big ICBMs that would be seen over the oceans/northern ice sheet in time for a counter-strike to be launched.

Re:Holy Mackerel!

[shma]

I don't think you understand what I'm saying. The experiment we're talking about in THIS article produced 10^-16 g of anti-matter. That's far less than the amount of matter converted to energy in the first atomic bomb.

Re:Holy Mackerel!

[Abcd1234]

Yes, you're missing something. Two words: Time Dilation.

Re:Holy Mackerel!

[clonan]

Question...

For the mass of fuel you mentioned, how much payload would you move to the target location?

Re:Holy Mackerel!

[Shakrai]

It's all an invention of American war-losers who still can't admit that they were beaten by people of "inferior race".

Given that we were there fighting on behalf of that "inferior race" I'd say that you deserved your troll mod. You'd have to look back to the Pacific Front in WW2 to find racial undertones in our campaign against someone.

Nobody in USSR cared about Vietnam (or China, or Yugoslavia, or Cuba, or Nicaragua, or Grenada...) enough to start a nuclear war.

No, they didn't. The USSR aided North Vietnam primarily to tie down the United States. We did the same thing to them in Afghanistan. This is how Great Powers play the game with other Great Powers in the nuclear age -- because the consequences of going to war directly are too horrible to contemplate.

Re:Holy Mackerel!

[Kayden]

How would that actually prevent the explosion? Wouldn't the magnetic field only prevent anti-matter/matter annihilation in a vacuum? There's plenty of matter in the air to un-create. Wouldn't the magnetic field either change the trajectory of the warhead or, at best, slightly shape the blast? I don't see how it could actually be neutralized.

Re:Holy Mackerel!

[Shakrai]

The display of force in Hiroshima and Nagasaki demonstrated that the weapons were too morally reprehensible to use against human targets

I don't see how you can claim that they were any more morally reprehensible than firebombing cities with conventional weapons. A civilian killed by a ton of high explosive is just as dead as one killed by a fission reaction.

As far as the "morality" of bombing civilians goes -- it was total war and the Axis powers bombed their share of civilian targets. Funny how few people mention this when they condemn the Allied powers for Hiroshima, Nagasaki or Dresden. There are some other cities I could mention: London, Warsaw, Coventry, Nanjing, Rotterdam, Belgrade, etc, etc, etc.

Re:Holy Mackerel!

[Anonymous Coward]

I may be wrong here, but your calculations are way off anything reasonable I might imagine - you didn't account at all for relativistic effects at all. A big question is how come you can travel faster than light (you cite 3.6 years for 4.9 ly for the nearest star).

And if you did account for relativistic effects, you should mention that the times you cite are subjective to relativistic speed, and when you get to Vega everyone who sent you will be long dead.

But why let numbers get in a way of a +4 Interesting (thank god not insightful) post.

Re:Holy Mackerel!

[Anonymous Coward]

IANAP, but you are, and you piqued my curiosity

So, please enlighten us how we can travel 1500 times faster that the speed of light to the center of our galaxy...

Re:Holy Mackerel!

[MikeBabcock]

Luckily there's already a "-1 for enemies" and you can just mark the person as someone you don't like the comments of if they annoy you.

Personally, you're too thin-skinned to have an opinion I'd care to contemplate -- I found the response somewhat entertaining.

Re:Holy Mackerel!

[Anonymous Coward]

You left out where the energy to sustain 1 gee is going to come from. Also with \gamma>>50 the blue shifted microwave background is not looking so nice.....

I find it far more interesting that .5c looks possible with a antimatter drive. It opens up the local stars at least.

Re:Holy Mackerel!

[SparkleMotion88]

The idea of a large-scale antimatter warhead being prevented from detonation by mere magnetic fields maintained by the nearest power plant is not an appealing idea.

I'm sure there is some way to get around the need for external power. Maybe the warhead could annihilate tiny amounts of payload in order to power a generator.

And the desire for anti-matter weapons will certainly be there. I agree with you that they probably won't be used in place of nuclear weapons. Instead, anti-matter can be used to create convenient semi-conventional weapons. That is, a small bomb/missile that could completely destroy (for example) a battleship or factory without any residual radiation or WMD-related scorn from the international community.

Re:Holy Mackerel!

[Anonymous Coward]

The first half is correct, but the second half is wrong. Since you're accelerating at a fixed 1 g in your timeframe, your engine is working at a fixed rate (the engine hum will be constant), so the fuel you need is proportional to travel time in the traveller's timeframe, not the distance traveled. This is of course assuming mass_ship >> mass_fuel, but I think you assumed that as well.

Re:Holy Mackerel!

[Anonymous Coward]

Errm. Slight problem. The speed of light is 300,000,000 m/s *not* 300,000 m/s (were you thinking of km?). That means the 'teaspoon bomb' is 1 million times more powerful, i.e. in the megaton range and plenty enough to level a very large city.

Re:Holy Mackerel!

[raynet]

Or even better, use antimatter explosives.

Re:Holy Mackerel!

[Anonymous Coward]

(I'm a theoretical particle physicist)

Then you should know that going over the speed of light is not really feasible ;)

Re:Holy Mackerel!

[jshackney]

Which raised the (very legitimate) question of why we were even in the conflict to begin with.

You should probably start your quest for answers with the French.

Re:Holy Mackerel!

[khallow]

You're using the wrong calorie. Should be roughly 2.8 kg. Here's the calculation:

1 ton TNT == 4.184*10^9 J
mass equivalent m = 60 megatons TNT/c^2 = 2.5104*10^17 J / (9*10^16 m^2/s^2) ~ 2.8 kg.

It's commonly misunderstood just how much mass in a nuclear bomb is converted to energy.

Re:Holy Mackerel!

[clonan]

Umm, all the time frames were quoted as from the point of view of the guy on the rocket.

He never said the rocket was traveling faster than light.

Re:Holy Mackerel!

[JohnFluxx]

> you didn't account at all for relativistic effects at all.

It fully takes into account SR effects.

> A big question is how come you can travel faster than light
It doesn't. All times as for the people in the spaceship, as I stated. The reason it takes less time is because of time dilation.

> when you get to Vega everyone who sent you will be long dead.
Indeed.

Re:Holy Mackerel!

[lymond01]

Well, if antimatter can make a clean explosion rather than a radioactive cloud, we may end up using it after all. The ability to wipe out a city, a mountain, a dam without any fallout would be a huge threat because people might actually use it.

Re:Holy Mackerel!

[JohnFluxx]

Time dilation and distance contraction. This are special relativity effects.

For the people on earth, the ship takes 4 million years to travel 4 million light years at close to the speed of light. But for people in the rocket, it can be a very short amount of time.

Re:Holy Mackerel!

[OrangeTide]

I assumed you were there by your name and knee jerk reactions. It does not mean you knew what the hell happened. You only know what you were told.

Maybe if you had degrees in economics and diplomacy I might take you more seriously.

Re:Holy Mackerel!

[Lord Apathy]

ve always thought the Cold War was more of a media thing than anything else

And you would be wrong. The Cold War was very much real. There was a number of time we came very close to nuclear extinction. One of my earliest memories of school happened in kindergarten. They where doing a nuclear attack drill, setting off the sirens, and getting the civil defense going and shit like that. They told us to get under our desks and put our books over our heads. Like that shit was going to help. One of the things that is burned into my memory while hiding there was the sound of the little girl behind me crying.

While the threat of nuclear annihilation is greatly diminished, the risk of nuclear war has increased. The US and Russia still have massive stock piles of aging weapons but its doubtful that we will use them in a full exchange. The threat of nuclear war on a limited scale is still there.

When a terrorist organization was to get a hold of a nuclear weapon they won't have as many qualms about using it. I say when because it is only a matter of time before one does. What will happen then? US policy has always been total retaliation with nuclear weapons if attacked with them. What will happen when a US city goes up under a terrorist mushroom cloud?

Re:Holy Mackerel!

[JohnFluxx]

> You left out where the energy to sustain 1 gee is going to come from

I gave the calculations for the energy/mass required to sustain 1g.

> Also with \gamma>>50 the blue shifted microwave background is not looking so nice.....

Shields :-)

Re:Holy Mackerel!

[JohnFluxx]

> The first half is correct, but the second half is wrong.

No it's not :P

> so the fuel you need is proportional to travel time in the traveller's timeframe, not the distance traveled.

The formula I gave isn't proportional to the distance traveled. it's a hyperbolic relation to distance.

> This is of course assuming mass_ship >> mass_fuel, but I think you assumed that as well.

The opposite - I assume mass_fuel >> mass_ship

Re:Holy Mackerel!

[Anonymous Coward]

I love this example because it demonstrates that a person can travel "faster than light" i.e. 10.5 light years in 4.9 years.

To the person there is in fact no limit to how fast he can travel, if he measures distance before he sets out.

To the outside observer he's never going faster than light, of course.

Re:Holy Mackerel!

[Anonymous Coward]

We've already done the whole Cold War/Mutually Assured Destruction thing.

Sure. And, following your line of reasoning, we won't do it again because we always learn our lesson the first time, which is why the lessons of history are never repeated.

Your unbridled optimism is clouding your reasonable reading of humanity's penchant for self-interest. Tell me that the suicide bombers still working in droves today are going to be repelled by the notion of mutually assured destruction. It hasn't yet, it's just smaller-scaled.

Re:Holy Mackerel!

[Anonymous Coward]

Note that

1 t ~ 4e9 J ~ 4e6 kJ ~ 1e6 kcal!

Re:Holy Mackerel!

[daem0n1x]

Yeah, those evil fascists killed thousands of innocent civilians. To show how much superior we are, let's do exactly the same.

Re:Holy Mackerel!

[cciechad]

You need to double that as the antimatter would react with an equal amount of regular matter but I think there must be some other flaw in your calculations as according to wikipedia 1 gram of antimatter would be equal to 43 kilotons of TNT.

Re:Holy Mackerel!

[techno-vampire]

Plutonium-238 will vaporize itself if you collect a large enough lump of it in one place and Pu-238 is a positively gentle decay compared to matter-antimatter annihilation.

Well, yes, but you have to remember that in the case of Plutonium, the reaction is taking place all through the sample instead of just on the surface. Makes a big difference in the rate, you know.

Re:Holy Mackerel!

[techno-vampire]

Of course. Bob Forward specified a lump the size of a bowling ball IIRC. He didn't cover what would happen if the anti-matter were in the form of a cloud of sub-atomic particles. That's why I specified a lump.

Re:Holy Mackerel!

[Anonymous Coward]

And how much time would have elapsed, on earth, if they returned the same way ? ( I am not a theoretical physicist )

Re:Holy Mackerel!

[hxnwix]

At a certain temperature, the lump starts to change into gaseous state. Then you start to change into gaseous state.

Re:Holy Mackerel!

[kwikrick]

For n=10.5 light years, this gives 4.9 years.

eh? speed of light? Relativity? Anyone?

Re:Holy Mackerel!

[Shakrai]

Yeah, those evil fascists killed thousands of innocent civilians. To show how much superior we are, let's do exactly the same.

No, to show them how much superior we are, let's win the war. It was a total war, remember? Every single source of the nation is poured into fighting and winning the war. Civilians working in arms production, logistics, research, etc, etc are legitimate targets in a total war. It's not pretty but what about war is?

Re:Holy Mackerel!

[techno-vampire]

Presumably Dr. Forward took that into account. I'd also presume he took the rates at which heat would be generated and would be dissipated into account. For a physicist, that's part of the job, you know.

Re:Holy Mackerel!

[Anonymous Coward]

So they lied to me in high school?

c/9.81 = 3.56e6 s = .968 year

Doesn't that mean that if you accelerate at a constant 9.81 m/s^2 for more than a year, you exceed the speed of light?

Wouldn't there also be the issue of navigation to avoid obstacles? What is the probability of going straight for 2 million ly without hitting something? 2 billion tons of fuel at light speed, that probably hurts.

Re:Holy Mackerel!

[joe_frisch]

Making positrons isn't all that hard. At SLAC we use about 20GeV to produce (and capture) 1 positron (efficiency is 1/40,000). Plans for a next generation accelerator did about 10X better. Making anti-protons (like fermilab) is MUCH MUCH harder. The problem is that a proton has 3 quarks and you need to make them all together - very unlikely. The fundamental process is something like 100,000X less efficient that making positrons. The LLNL experiment is still very interesting science, but it doesn't lead in any obvious way to efficient production of antimatter.

Re:Holy Mackerel!

[Anonymous Coward]

Thank you for these calculations...they are quite inspiring.

BTW, what would the mechanism of your engine be? How would we account for conservation of momentum?

Re:Holy Mackerel!

[JohnFluxx]

Pretty much just the distance travelled, times 2, in years.

So going to Andromeda galaxy and back again (2,000,000 light years) would take 56 years according to the person in the spaceship, and he would come back to a world that has aged 4 million years.

Pretty mind blowing.

Re:Holy Mackerel!

[JohnFluxx]

You're forgetting about time dilation, just like everyone else that has replied to my comment asking about this. Time slows down for the people in the space ship (or viewed another way, the distance is length contracted)

Re:Holy Mackerel!

[JohnFluxx]

As you accelerate, you 'just' get closer and closer to the speed of light and time slows down for the people in the spaceship. This is what this is all based on - that the constant acceleration means that time slows down more and more for the people on the space ship.

At the peak speed for travelling to another galaxy, say, they will still only be travelling close to the speed of light, but a million of years will pass on earth for something like a year or two for the people in the rocket.

> Wouldn't there also be the issue of navigation to avoid obstacles?

Yes, a huge issue. After accelerating for just one year, the heat that exists in space (microwave background cosmic radiation) will be hitting the spacecraft will be hotter than any known material could withstand.
We would have to have some sort of 'light shield' that we have not yet invented or something.

Re:Holy Mackerel!

[JohnFluxx]

> BTW, what would the mechanism of your engine be?

Some sort of mechanism to turn mass into light.

Combining matter and antimatter would be a good candidate, although I assume we can do so with 100% efficiency. We can currently reach 50% I think, which is probably good enough.

> How would we account for conservation of momentum?

The light carries the momentum.
For momentum to balance, you have to have that:

fuel_mass * fuel_velocity = ship_mass * ship_velocity

But you also don't want to carry lots of fuel. So you want the fuel_mass to be very very small and the fuel_velocity to be very very large. The natural candidate is to thus emit light itself. (In this context, light has (relativistic) mass)

Re:Holy Mackerel!

[nsteinme]

Don't your calculations require the assumption of Newtonian physics? If I follow your math correctly, if you travel 10.5 ly in 4.9 years, you are exceeding the speed of light.

Re:Holy Mackerel!

[Anonymous Coward]

Unfortunately, that's only true to a point. The chance of a nuclear exchange is still uncomfortably high. Nuclear weapons are a cornerstone of modern American military doctrine, so any conflict could turn nasty rather quickly.

Re:Holy Mackerel!

[Alex Belits]

I assumed you were there by your name and knee jerk reactions. It does not mean you knew what the hell happened. You only know what you were told.

Really? Living and working there I would somehow miss important details of economy and structure of USSR/ex-USSR society that some American asshole raised entirely on anti-USSR/anti-Russian propaganda would know? That would require more tinfoil than ever was used (or mentioned) by American conspiracy nuts, and US has plenty of conspiracy nuts.

Maybe if you had degrees in economics and diplomacy I might take you more seriously.

And only from American university, where they stuff your heads with propaganda formulas, right? Don't tell me, "degree in economics" means anything but belonging to one of your conflicting "schools of economics" with purely ideological statements at the core of their dogmas. Oh and diplomacy... like who, Condoleezza Rice?

Re:Holy Mackerel!

[Alex Belits]

Given that we were there fighting on behalf of that "inferior race" I'd say that you deserved your troll mod. You'd have to look back to the Pacific Front in WW2 to find racial undertones in our campaign against someone.

Oh, Americans, defenders of people of every race again themselves. Why oh why are you hated by all non-Americans?

No, they didn't. The USSR aided North Vietnam primarily to tie down the United States. We did the same thing to them in Afghanistan. This is how Great Powers play the game with other Great Powers in the nuclear age -- because the consequences of going to war directly are too horrible to contemplate.

This is what they told you? Really?

USSR cared as much as those countries were close to USSR borders. Of course, being American you couldn't possibly know that Afghanistan shared a border with USSR. With Vietnam, if anything, USSR cared more about effect on China (that, again, was across the border and had very strained relationship with USSR) than some stupid Yanks scoring some worthless allies in that poor and massively fucked up region.

But nooo, for Americans it's less an embarassment if it was some kind of proxy war and massive conspiracy to make them less glorious than they were supposed to be. What a bunch of losers.

Re:Holy Mackerel!

[JohnFluxx]

> Don't your calculations require the assumption of Newtonian physics?

No, this is an integration of the special relativity lorentz transformation.

Re:Holy Mackerel!

[Anonymous Coward]

I wish this post could be placed at the top of the page. After a while all "funny" posts start to seem the same old. Just another stupid internet meme. It's nice to see someone using their brain a little. For that matter I'm surprised you even post or read slashdot.

Re:Holy Mackerel!

[Ifandbut]

Yes, a huge issue. After accelerating for just one year, the heat that exists in space (microwave background cosmic radiation) will be hitting the spacecraft will be hotter than any known material could withstand.
We would have to have some sort of 'light shield' that we have not yet invented or something.

What about those cloaks we have been seeing alot about. We can make materials that are invisible to some wavelengths of light so it would just be a matter of adapting it to a large scale with a wide range of wave lengths. Citation: http://en.wikipedia.org/wiki/Metamaterials#Cloaking_devices
This is not counting actual space dust impacts because that would tear a hole through it very fast. However, I think this is basically the 'light shield'.

Re:Holy Mackerel!

[Anonymous Coward]

I don't see how you can claim that they were any more morally reprehensible than firebombing cities with conventional weapons. A civilian killed by a ton of high explosive is just as dead as one killed by a fission reaction.

Thats easy enough, the nuke leave cancer causing materials in the land for a great many years to come, while the firebombing is much more easily cleaned up.

You use a nuke to not kill, but exterminate your target and curse their children for a thousand generations.

"Modern" warfare is all about genocide and ethnic cleansing now, the whole point is no longer just to defeat your enemy, but to poison his land and his bloodline in the hopes that he dies a slow and painful death through disease and pestilence long after the battle has been fought.

In many ways it's worse then some medieval tactic of dropping bubonic plague into your enemies water supply.

Don't believe me? You can start by looking up rates of cancer and birth defects in the areas around Hiroshima and Nagasaki, Agent Orange in Vietnam and "Gulf War Syndrome" in the current and previous wars in Iraq and Afghanistan do to the use of chemical and depleted uranium rounds. you don't have to drop the big one anymore to leave the battlefield a nuclear wasteland.

All things considered, I'd say that the napalm bomb isn't all that bad for those that come after the fire is out.

Re:Holy Mackerel!

[Anonymous Coward]

I really don't understand how you propose to travel 4.3 ly in less than 4.3 years and so on...

What am I missing ? Is this due to relativistic effects making the ship clock run slower than an outside observers clock ?

Please enlighten me... If it takes light an x amount of time to move from point a (some star) to point b (some other star) then the distance in lightyears is what an outside observer sees, but for the photons themselves the transfer appears to be instantaneous ? (because they do not take any time at all to accelerate ?)

Aaarghhh... this relativity stuff makes your head ache :)

I've already moderated elsewhere in this thread (on stuff that did make sense to me) so posting this anonymous.

Re:Holy Mackerel!

[Shakrai]

being American you couldn't possibly know that Afghanistan shared a border with USSR.

What a waste of a three digit UID if all you do with it is repeat bad stereotypes and troll. Wanna trade user accounts? You can troll with my six digit UID and even have the benefit of good karma while it lasts.....

Re:Holy Mackerel!

[MarkTina]

What happens when your little space ship hits a bit of dust ? :-)

Re:Holy Mackerel!

[ceoyoyo]

There are a few other concerns. The process is about two thousandths of a percent efficient. And uses lasers. If you were going to scale it up to produce enough antimatter to be useful for propulsion you might as well just point the necessary lasers at your spaceship and use a solar sail. No fuel carried trumps even antimatter fuel.

Re:Holy Mackerel!

[JohnFluxx]

Please have a look at some of my other replies to people asking the same thing.

> Is this due to relativistic effects making the ship clock run slower than an outside observers clock ?

Yes. Time dilation.

>but for the photons themselves the transfer appears to be instantaneous
Yeah photons do not experience time or even distance. For them, everything is at the same place at the same time. You get zeros and infinities in the equations.

Re:Holy Mackerel!

[expatriot]

I not sure what you meed by 2,000,000 ly in 28 years. Obviously you cannot accelerate that much because of the hard limit of light speed (and the effect of increasing mass as you approach light speed).
Of course if you mean some radically new and unimaginable technology, why not assume you can get there in five seconds.

Re:Holy Mackerel!

[JohnFluxx]

Hi, please see my other replies - a lot of people have asked the same thing! The answer, basically, is time dilation. Time for the people in the ship will slow down. While it will take 2 million years for people on Earth, it will only take 28 years for the people in the ship.

You could get there in 5 seconds, but the acceleration would pulp you.

Re:Holy Mackerel!

[OrangeTide]

Really? Living and working there I would somehow miss important details of economy and structure

Living and working in America doesn't appear to make Americans experts on the situation either.

And only from American university

I'd accept Danish, Belgium, Canadian, English or French universities as well as numerous others.

Oh and diplomacy... like who, Condoleezza Rice?

I can name numerous people with degrees in diplomacy and/or economics. Listing names achieves what goal again?

(look at the knee jerk reaction to all the things he imagined I would say, when he has no clue what anyone's position is. Not the Russian government, and not some random slob on the internet)

Re:Holy Mackerel!

[Anonymous Coward]

Slight problem is that you'd need tonnes of the stuff to maintain 1g for years.

Re:Holy Mackerel!

[Johnno74]

Ahh ok. Sorry, You're quite right :)

Re:Holy Mackerel!

[BCGlorfindel]

What would happen if you aerosolized said cube with a small explosive?

I presume you mean a small explosive like, say, I dunno, anti-matter?

Re:Holy Mackerel!

[Tenebrousedge]

Look, I don't care about whatever point you're trying to make. I'm sure you feel very strongly about it, too, but could you please try to be less of an asshole when making your points?

Rhetoric used to be an art form. How sad that the educated are not now taught to express themselves.

If I may weigh in on the topic of your discussion, I would say that both of you need further proofs: neither having lived in a country, nor having a degree are sufficient evidence of much of anything. Since the matter being discussed is mostly a matter of historical fact, you should probably dig up some economic records of some sort. But I suspect you just want to rant and froth a bit; I'll leave you to it.

Re:Holy Mackerel!

[Anonymous Coward]

which is why in star trek, when they were creating their torpedos, they broke apart the matter and antimatter into very small masses, and interwove them together. the smaller the particle and the more even the mix, the more bang and less fizzle.

also in star trek, they created a stream of a small mass of antimatter and matter, instead of just mixing reagents. they had the tech to just dump them together i guess, but the energy output would be more disappointing.

so the same is true for a powerplant, starship, or weapon... you have to create an even mixture at a very small particle size to have any real effect...

seems someone built in a very clever safety mechanism. but when we manage to override it, will we open up new dangers?

Re:Holy Mackerel!

[mknewman]

If you accelerate at 9.8m/s^2 for half the journey and -9.8m/s^2 for the second half of the journey (so that it's just like earth's gravity) then you would arrive at the planet after: 1.94 arccosh(n/1.94 + 1) years For n=10.5 light years, this gives 4.9 years. For other values of distance: 4.3 ly nearest star 3.6 years 27 ly Vega 6.6 years 30,000 ly Center of our galaxy 20 years 2,000,000 ly Andromeda galaxy 28 years

Doesn't anyone else see a problem with this? You are talking about exceeding the speed of light. The MINIMUM it's going to take to go 4.3 ly is 4.3 years. Your formula is wrong.

Re:Holy Mackerel!

[Anonymous Coward]

I know this is slashdot... but did you *really* have to go and figure that one out?

Re:Holy Mackerel!

[EdIII]

I'm not fear mongering. With all due respect you should read comments completely and maybe even look to the parent post to understand the conversation before making your contributions.

I understand what you are talking about with anti-matter weapons and I will stipulate for the purposes of *this* conversation that you are 100% correct.

What I was speaking to was the concept of Mutually Assured Destruction. The other poster was trying to say we should have no fear at all about this technology *possibly* being used for a weapon since M.A.D will protect us all from each other.

My statement that you quoted holds true as long as you assume anti-matter weapons could be created as dangerous as the other poster said they could be. Substitute whatever technology you want. StrawBerry Shortcake Super Muffins. It makes no difference.

My comment was on human behavior regarding weapons of mass destruction, not on any specific technology on how to create them.

Re:Holy Mackerel!

[Anonymous Coward]

So in anti matter bomb there will be a blender, probably :)

Re:Holy Mackerel!

[mknewman]

No, you are missing something. Relativistic effects. As you gain speed your mass goes up. Higher mass means less acceleration, and you don't pass GO (186,423 miles/sec).

Your calculations and the ones on the C-Ship page are wrong, they assume infinite acceleration past light speed. In reality you will never get past light speed so the shortest time it will take you is slightly slower than a beam of light. 30,000 ly to the center of the galaxy will take YOU 30,000ish years, where observers on the Earth will think you took millions of years.

Re:Holy Mackerel!

[Anonymous Coward]

Phew, good thing you posted. Nobody else saw any problem with the GP's post.

Re:Holy Mackerel!

[sdpuppy]

Ah - OK, sounds good. I like my oatmeal lumpy, why not antimatter?

Should be interesting to try (but when you try it, I'll still stay behind this little plastic shield at a reasonable distance, think maybe 3,000 miles would be enough just in case? :-) :-) Even if there isn't a big boom, my doctor advised me to limit my exposure to gamma rays since my skin started turning orange and chunky

Re:Holy Mackerel!

[JohnFluxx]

An iron meteorite typically has a density of 8000 tonnes per cubic meter. To fuel a craft to another galaxy, you'd need 2 spherical meteorites, each 1km wide. One made of matter, one made of anti-matter.

While this is large, we can pick up the 1km wide matter meteorite easily in space. So to travel 2 million light years to another galaxy requires us to 'only' produce a sphere 1km wide of anti-matter. This isn't really doable at the moment, but it's hardly a fantastical feat.

Re:Holy Mackerel!

[Anonymous Coward]

You sure sounded like a rocket scientist to me.

Re:Holy Mackerel!

[Abcd1234]

No, you are missing something. Relativistic effects. As you gain speed your mass goes up. Higher mass means less acceleration, and you don't pass GO (186,423 miles/sec).

So? That doesn't change the fact that, as you reach velocities that are a significant fraction of c, time dilation means that, from the perspective of the traveler on the ship, they can traverse a distance of 10.5 ly in less than 10.5 years. To quote Wikipedia (that bastion of truth):

Time dilation would make it possible for passengers in a fast-moving vehicle to travel further into the future while aging very little, in that their great speed retards the rate of passage of on-board time. That is, the ship's clock (and according to relativity, any human traveling with it) shows less elapsed time than the clocks of observers on Earth. For sufficiently high speeds the effect is dramatic. For example, one year of travel might correspond to ten years at home. Indeed, a constant 1 g acceleration would permit humans to travel as far as light has been able to travel since the big bang (some 13.7 billion light years) in one human lifetime. The space travelers could return to Earth billions of years in the future. A scenario based on this idea was presented in the novel Planet of the Apes by Pierre Boulle.

Of course, from an outside viewer's perspective, it'll take (in our original example) 10.5 years, period.

Incidentally, this effect has been demonstrated in satellite experiments. Clocks onboard satellites become skewed relative to clocks on the ground because time, from the perspective of an outside observer, actually passes slower on the satellite. Conversely, this means that, from the perspective of the clock on the satellite, it actually travels further, in absolute terms, than it's velocity (as we on the ground observe it) should allow... not unlike the passenger on our relativistic ship. And this effect is so pronounced that GPS satellites actually have to compensate for it.

Now, it's also true that, as you approach c, you need more and more fuel to sustain your acceleration, but that's a separate issue, and I have no idea if the OP included that as part of his/her required reaction mass calculations.

Your calculations and the ones on the C-Ship page are wrong,

Umm... given I'm not the OP, I don't have any calculations. :) That said, I'm afraid it is you that's incorrect. I'd suggest doing a little reading on time dilation and SR.

Re:Holy Mackerel!

[skavenger]

You don't? Firebombs (or any other form of generalized attack) are certainly devastating and morally reprehensible when dropped on population centers. They can make people exposed to the explosion and resulting fire just as dead as someone killed by a nuclear blast. What they don't do is cause radiation poisoning, irradiated water, plants, and wildlife, birth defects, and all the other things associated with exposure to high levels of radiation. Oh, and those nasty consequences of the application of nuclear weapons are also present in the production and testing prior to military application.

Still care to argue that there isn't a meaningful distinction?

Both forms of attack are reprehensible, but also distinct. The nature of the conflict does not change this. The agent of destruction does not change this. Your straw man could be vaporized or incinerated, it's just as weak.

Re:Holy Mackerel!

[Alex Belits]

Living and working in America doesn't appear to make Americans experts on the situation either.

US economy is not designed as a giant nonprofit with most of the trade limited to domestic economy, like USSR system worked -- in US it's possible to create or conceal massive economic crisis or boom for years by mere manipulation of debt and foreign trade, as we can see on the example of the last two decades. USSR economy, with all its secrecy at the local level, was way too big and way too monopolized by the government to hide anything important -- it was pretty obvious that between 70's slow growth and mild recession in early 80's it could have done better, however if growth of production outpaced growth of population (the only way to truly get in trouble for a "giant nonprofit" like USSR), it would be immediately visible -- there would be shortages of products, unemployment and sudden massive replacement of domestic production with easily recognizable imports in short term followed by visible decrease in quality of life for most of the population. This is not what happened -- oil trade became less profitable, so local industry had to pick up the slack, however merely fixing 70's policies that were widely regarded as irresponsible complacency would be sufficient.

As it was revealed later, Gosplan (the guys with then-state-of-the-art capability to analyze and simulate domestic economy, and with all data about all transactions collected for them by the rest of the government) projected continuation of recession and slow improvement but neither crisis nor boom in the foreseeable future up to the year 2000. Taking into account that they had to be conservative, and could not take into account accelerating progress in technology that only started later (and greatly improved the economy of China, Taiwan, South Korea, etc.), USSR could dedicate a small percentage of its enormous production capabilities to electronics and get far ahead of those predictions -- still with no crisis and minor economic reforms.

However in late 80's population's EXPECTATIONS of the economy changed way before anything changed in the economy itself. After being spooked by visible mild recession, Gorbachev's government performed a massive propaganda campaign promoting supposed wealth and stability of Capitalism, trying to pave a way to its still-undecided-on economic reforms along with their (already successful and welcomed by the population) political reforms. Propaganda campaign included some pretty wild claims about quality of life and availability of consumer products, housing, etc. in "the West" and specifically US, and denigrated everything that was then available in USSR, making an impression that "something has to be done" and "oh noes, I don't have a house and two cars".

Communists thought, it would be a great idea to reuse (again, then-current) Reaganites' anti-Communist propaganda to support their reforms of supposedly "failed system". Much of that spilled into population's consciousness, and this is why Americans heard so much pleasant noises from Russia/USSR at that time. Despite initial acceptance, reforms were a massive failure, and caused real, easily visible slide into poverty and deterioration of infrastructure -- that was visible in mid-90's when USSR and its "nonprofit" economy were all but memory.

It was the greatest weakness of their system that few idiots at the top can cause massive amount of destruction on a whim, however they were hardly unique in this way -- just look what Social Conservatives did to US, and they didn't even have to reform anything.

I'd accept Danish, Belgium, Canadian, English or French universities as well as numerous others.

Aren't those treated in their respective countries as glorified accountants? Certainly in no European country it as a secret that economic policy is dictated by whatever party or coalition of political parties is in charge, and all pretenses that it's somehow "scientific" are seen as quacker

Re:Holy Mackerel!

[Alex Belits]

Look, I don't care about whatever point you're trying to make. I'm sure you feel very strongly about it, too, but could you please try to be less of an asshole when making your points?

Why would I? Being an asshole is the cornerstone and starting point of every claim that my proud American friends ever made about economy.

Rhetoric used to be an art form. How sad that the educated are not now taught to express themselves.

It is needed as an art form when people have to conceal facts.

If I may weigh in on the topic of your discussion, I would say that both of you need further proofs: neither having lived in a country, nor having a degree are sufficient evidence of much of anything.

Eyewitness evidence is now as bad as regurgitation of propaganda op-ed pieces, right? Great standards you have here...

Since the matter being discussed is mostly a matter of historical fact, you should probably dig up some economic records of some sort. But I suspect you just want to rant and froth a bit; I'll leave you to it.

What records? Volumes of production and government budget from 80's USSR? The figures that became available are nowhere close to claims that American "economists" made at the time, especially claims about huge percentage of military spending (why would it when neither military nor civilian production involves profit?). What else do you want -- my paycheck stubs, university services lists and grocery receipts from 80's? I don't think, I kept those.

Re:Holy Mackerel!

[Alex Belits]

Oh noes, people disagree with you.

Re:Holy Mackerel!

[Tenebrousedge]

Why should you not be an asshole? Because it's unpleasant to read and does not lend support to your argument. No matter if you've argued with friends in the past over this; they aren't here now, and most people here are either not American or not compelled to be an asshole as a matter of course. You can't win yesterday's argument by being savage today.

Rhetoric is necessary to influence people. It is what distinguishes effective communication from mere words strewn on a page. Concealing fact can fall within the bounds of an effective argument, but this is not generally the case. Also, there are other ways of concealing fact. Secrecy, for example, is probably far more effective than rhetoric.

Eyewitness evidence is notoriously unreliable, and your own unsubstantiated opinion is fit for no purpose that I'm aware of. The same is true of this other fellow, and of myself: none of us have any more inherent credibility than any other. To promote your view, then, you must have a well-written argument, or have a set of facts that speak for themselves. Since you have no apparent aptitude for the former, the latter is necessary.

As to the standard of proof, that is for your opponents to decide. I think you'll find the bar is set rather low; I would accept anything more reliable than opinion. You could probably even find an economist that you liked and argue why his opinion should be considered reliable. Facts and figures would, of course, be appreciated.

Perhaps you could write a Journal on this subject, since the discussion here is likely over.

Re:Holy Mackerel!

[OrangeTide]

I see it doesn't make you an expert on US economics either. neat.

Re:Holy Mackerel!

[Anonymous Coward]

You can't abuse Lorentz contraction this way in non-flat spacetime. It's true that in SR (which applies to Minkowski spacetime only) length contraction falls out of the preservation of Galillean invariance, so in the frame constructed such that a traveller, his or her space ship and a clock are all at rest, the clock will report a surprisingly short interval while at relativistic speeds versus the bulk of matter in the Milky Way. However, in GR you need to construct a valid solution to the Einstein field equations, and there you run into massive (pun intended) problems with tidal effects on your constructed frame of reference precisely because real spacetime is *not* Minkowski spacetime.

Try it: choose a geodesic which will avoid large scale gravitational accelrations at low speeds and then solve the EFE for that geodesic bearing in mind the nature of spaceship, passenger and clock. Note that momentum becomes a factor ("Einstein stress energy [momentum] tensor" for a reason) at relativistic speeds through even *fairly* flat spacetime, and this transforms to differential off-axis accelerations of components of the spaceship-passenger-clock system. Along realistic courses through the galaxy, these accelerations are large enough to overwhelm structural integrity, and the result is that your system shakes apart spectacularly. This is easier to reason about if you analyse the system from another frame, such as one in which there is no dipole redshift in the arms of the galaxy (spacetime looks quite corrugated in that frame, something like Newton's rings).

As an analogy think about a powerboat traversing water which has only a few minor ripples; at low speeds the boat hardly notices, but at high speeds the boat is bounced around dangerously (racing speedboats might even flip end over end or break apart when hitting a small wave). The key here is that a *mostly* flat field of water transforms into dangerous accelerations when an object traversing that field has sufficient momentum.

For a more practical example, consider Einstein lensing, where a photon (or, more usefully, many photons following very similar geodesics) acquires substantial off-axis accleration as it experiences weak changes in the gravitational field.

There are other objections to structures moving at speeds very closely approaching c, but the key one is that dissociation of structures is expected when you cannot construct a frame of reference such that advancing on axis components and receding components never develop momentums approaching their binding energies. (Another way of looking at this is escape velocity differences in components of a structure versus acceleration of the whole structure; or: why are rockets launched from near the equator, and where does all the Earth's helium go?)

Re:Holy Mackerel!

[Alex Belits]

Why should you not be an asshole? Because it's unpleasant to read and does not lend support to your argument. No matter if you've argued with friends in the past over this; they aren't here now, and most people here are either not American or not compelled to be an asshole as a matter of course.

Why would I care about feelings of people whose most dear beliefs and positions I am trying to discredit?

You can't win yesterday's argument

What "yesterday argument"? Americans' unwavering belief in their glorious history is very much the current problem.

by being savage today.

Being someone's enemy does not make me a savage.

Rhetoric is necessary to influence people. It is what distinguishes effective communication from mere words strewn on a page. Concealing fact can fall within the bounds of an effective argument, but this is not generally the case.

I would rather express my idea in the form that can be judged by the content. Smart people will get it, and I am not interested in convincing dumb people, humiliating them is good enough.

Also, there are other ways of concealing fact. Secrecy, for example, is probably far more effective than rhetoric.

Conceal facts that are already announced by your opponents, so rhetoric is used to twist their meaning and distract the observers. I thought, that was pretty obvious.

Eyewitness evidence is notoriously unreliable, and your own unsubstantiated opinion is fit for no purpose that I'm aware of.

As opposed to what, political propaganda that is reliable in being wrong, misleading and manipulative? Appeal to authority when my original claim is that authority figures are lying? It's not like my experience is not backed by tens of millions of other people who had seen the same (though most wouldn't bother talking to Americans unless you ask them).

To promote your view, then, you must have a well-written argument, or have a set of facts that speak for themselves. Since you have no apparent aptitude for the former, the latter is necessary.

Really? Actually I did both, it's just the result is something you don't like, so you can't accept it. Congratulations, you are a true American patriot.

Re:Holy Mackerel!

[JohnFluxx]

Which is why I specifically stated that my equations will not hold for distances larger than a galaxy, where you require GR.

Re:Holy Mackerel!

[Alex Belits]

Oh yeah. Experts on US economy. The people who were explaining you under Reagan how trickle down works. The people who were explaining you under Clinton how stock market speculation and some kind of uniquely American capability to profit from technology can sustain your economy forever. The people who were explaining you under Bush how there is no economic ill that can't be solved by a $300 tax refund advance. The people who paraded inflated GDP numbers in front of you without telling you how it includes hidden debt and inflation. The people who declare recessions two years too late after they sort out the numbers doctored over the previous year. The people who pretend that current debt crisis is caused by bad loans as opposed to be the result of the same cause -- the whole economy fueled by overstretching debt and trade deficit.

I see why you believe that it was possible to completely conceal some kind of disaster in USSR economy -- because you project onto others what you don't dare to admit about your own country.

Re:Holy Mackerel!

[Tenebrousedge]

Why would I care about feelings of people whose most dear beliefs and positions I am trying to discredit?

Don't care about their feelings, care about the feelings of the people who you are trying to persuade.

What "yesterday argument"? Americans' unwavering belief in their glorious history is very much the current problem.

Given the wide publication of 'A People's History of the United States' and other similar literature, I would say that is an overbroad generalization. "Yesterday's argument" is explained by the context of that sentence. I am sure that re-reading my post will clear up that difficulty for you.

Being someone's enemy does not make me a savage.

I'm sorry if your English isn't very good, but it is not necessary to be a savage to be characterized as having savage behavior. That error almost seems deliberate.

I would rather express my idea in the form that can be judged by the content. Smart people will get it, and I am not interested in convincing dumb people, humiliating them is good enough.

Your content is spurious and devoid of anything but self-righteous vitriol.

Conceal facts that are already announced by your opponents, so rhetoric is used to twist their meaning and distract the observers. I thought, that was pretty obvious.

You must not have actually read what I wrote.

As opposed to what, political propaganda that is reliable in being wrong, misleading and manipulative? Appeal to authority when my original claim is that authority figures are lying? It's not like my experience is not backed by tens of millions of other people who had seen the same (though most wouldn't bother talking to Americans unless you ask them).

Perhaps you have a problem with only reading what you want to read. Back your assertions. If tens of millions of people agree with you, there should be some indication of that. Probably out of tens of millions you can even find an economist. Hell, you can't even find the "authority figures" you're railing against. Who are you fighting here? Do you have this argument in the mirror each morning?

Really? Actually I did both, it's just the result is something you don't like, so you can't accept it. Congratulations, you are a true American patriot.

Now this is just slander and projection. Clearly you cannot distinguish between criticism of what you say and criticism of how you say it. If you'd taken the time to comprehend my statements, you'd find that I have been focused solely on the latter.

"I did both." Bullshit. Your writing is abysmal, and you have no facts, and a single vehement assertion. How many ways can I rephrase this? You can't just jump to the end of the argument, declare victory, and have done. If events happened as you say they did (and we have no particular reason to doubt you), then they can't have vanished into a void. There must be some evidence---produce it.

Understand that what you're doing is the equivalent of saying (with great rancor) that the mountains on Pluto are green. Despite what you think, few people really care one way or another. However, while there is no particular reason why what you say should not be true, it is not made true merely by your word alone.

If you cannot muster any evidence, then you are no different than the stereotypical American you deride. Your militant belief in your own self-righteousness is identically despicable.

Re:Holy Mackerel!

[Anonymous Coward]

The issue of scale comes in not from distance but from speed.

With increasing speed particles gain energy.

With increasing speed fields gain energy too.

That is fundamental to GR, and is required for Galillean invariance at high speed.

Looking at it from the Gallilean perspective: inside the ship, variations in the gravity field will be like waves; as the ship speeds up relative to the gravity field, the amplitudes of the field will be felt to increase. Enough amplitude and the ship breaks apart. Outside the ship, from an observer who is moving is much slower relative to the gravity field, as the ship speeds up relative to the gravity field, ship's constituent particles will be so energetic that they will be strongly deflected by low-amplitude variations in the gravity field.

You do not need galactic scales, you merely need enormous speed relative to a field with which the ship's components will couple. The two important ones with which it will couple will be gravity and electromagnetism. As with an increase in energy of photons (excitations in the electromagnetic field), the ship will observe an increase in the energy of gravitons (excitations in the gravity field).

At speeds very near the speed of light, even very small, gentle, slow-rolling fields become quite violent, leading to possibly large second, third and fourth derivatives of velocity.

Moreover, even thinking just about gravitation expressed in geometry terms, relativistic speeds lead to an experience of highly curved space (stress energy tensor, after all) which leads to the same sort of accelerations (and 1st, second, and third derivatives of acceleration).

This is a real issue as we dramatically decrease proper_length / \gamma(\nu); our ship is riding over increasingly narrow but increasingly tall waves in spacetime, or experiencing increasingly large and increasingly rapid changes in amplitude of scalar fields.

As with the problem in dealing with extremely high energy photons colliding with the front of the ship, even though to a relatively still outside observer those photons look low energy, the ship will also be experiencing extremely deep deformations of spacetime, even though spacetime looks pretty flat to a relatively still outside observer.

A small bit rock would do enormous damage collision-wise with the ship even at fast, but nonrelativistic, closing speeds. The same bit of rock given relativistic closing speeds would experience the huge deformation in spacetime the spaceship's huge energy would produce; alternatively (by Lorentz transformation) the spaceship would experience a huge gravitational acceleration produced by the approaching rock.

Likely result at very high relativistic speeds: ship and small rock tear each other apart tidally.

You are right though that the gravitation of the galaxy would be important at large ranges, because it would act as a brake on the space ship, just as it does for extremely high energy particle radiation (cosmic rays). There is a recent discussion of this on Phil Plait's badastronomy blog, in fact. Tidal effects would come into play given differential accelereation among the component particles of the relativistic space ship. Parts of the ship would slow down more than other parts, and rigidity does not work as you might expect in highly curved spacetime, as you would have around a ship with high rest mass moving at very high speed relative to the bulk of the milky way galaxy. As \gamma(\nu) increases, the milky way galaxy's mass starts looking a lot like a black hole from the perspective of a passenger in the spaceship; at some point you cross the point at which you calculate an escape velocity greater than the binding energy of some components of the ship. Rip!

With a sufficiently large \gamma you get this from much smaller masses, even Msun as you depart the solar system or enter the target one. With a sufficiently large \gamma you get this from asteroid masses or even smaller. ISM or even unseen mass

Re:Holy Mackerel!

[JohnFluxx]

Thanks for the reply. I was thinking about your previous reply last night - I didn't mean to reply to you in such a terse form.

I will reread what you've written and think about it all some more - thank you.

Do you have any suggestions on what to read for this? Thanks

Re:Holy Mackerel!

[Anonymous Coward]

Sure, a good first starting point is Carroll, Sean, "Spacetime and Geometry: An Introduction to General Relativity". 2003. ISBN 0-8053-8732-3

A good chunk of the book walks you through the maths you need to deal with GR, notably differential geometry. A decent library will have a copy you can leaf through before digging into your wallet; it's not really geared for outright beginners -- it helps to have a good understanding of quantum and classical electrodynamics, special relativity and calculus, but you won't need University-graduate-level maths or knowledge, and the book is no substitute for grad courses (although it might be used in one!)

Schutz, Bernard F., "A First Course in General Relativity". 1985 978-0521277037 is easier and more didactic, but shows its age a bit with respect to things like Einstein Lensing, and missing mass issues (after all it predates BOOMERANG by a decade or more...) Schutz's math books are good too (and so are Schaum's).

If you want much harder than Carroll, he has an excellent bibliography, and there's always arxiv's qc-gr :-) :-)

However, 't Hooft's bibliography is online http://www.phys.uu.nl/~thooft/theorist.html and also worth reading. 't Hooft also recommends Carroll, fwiw. He also recommends his own book, which is hard compared to Carroll's.

't Hooft is one of the people you will want to read if you find SR, GR and QED easy. (In fact, if you do, sign up as a part time student doing physical cosmology!)

While you're thinking, analytically, your relativistic journey is pretty similar to Supplee's paradox in the presence of nonuniform gravitation. Matsas's arxiv preprint is here and is very steep for anyone, which is why I'm not typing any mathmode stuff here (not that slashdot supports it...). Supplee's ocean is somewhat analogous to the natural realization of free space, and the sub is directly analogous to your relativistic space ship -- the analogy is closer if you fly a geodesic above the plane of the galaxy, such that the mass halo can be seen as the surface of the ocean and the more visible mass forms the ocean floor, with "neutral buoyancy" being a constant acceleration towards the plane of the galaxy.

This geodesic is necessarily something like an arc seen from a nonrelativstic observer looking edge-on at the galaxy, since there is more mass towards the middle of the milky way than towards the edge.

But what does the ship do as it accelerates? Does it follow this arc as planned, or is it accelerated downwards towards the plane of the galaxy or upwards away? Is this gravitational acceleration uniform (this is not in Supplee's paradox, it requires thinking about the distribution of matter) at a given speed? What happens to any non-uniformity as the ship accelerates along the planned arc? etc.

If you can grok the idea of different large clumps of stars in the galaxy influencing the spaceship flying over top of the galaxy, then narrowing that down to a spaceship flying through the galaxy (which because of the inverse square law is much lumpier spacetime!) should be straightforward. :-)

Sorry about drowning you in this stuff. You are right about Lorentz-Fitzgerald contraction happening, and would be right in an ideal flat spacetime about the practicality of relativistic interstellar or intergalactic travel with respect to the lifetime of a traveller. Unfortunately real spacetime is not flat at all, so special relativity is an insufficent toolset for this problem, and your traveller's lifetime would be dramatically shortened by a rather spectacular local shaking apart.

Re:Holy Mackerel!

[JohnFluxx]

I tried with Sean Carroll's No Nonscense Guide To GR a while ago, and found it quite difficult to follow - he moves quite rapidly without any real exercises to do to check that I understand it.

It's certainly interesting.

Re:Holy Mackerel!

[Alex Belits]

Don't care about their feelings, care about the feelings of the people who you are trying to persuade.

I am not trying to persuade American patriots -- most of them are incapable of changing their opinions. My arguments are intended for the benefit of the observers. I can change my opinion if presented with convincing argument supported by facts, however "How do you dare not to believe in what I believe?!" does not count as such.

Given the wide publication of 'A People's History of the United States' and other similar literature, I would say that is an overbroad generalization.

Publishing dissenting books does not change the prevailing public opinion.

"Yesterday's argument" is explained by the context of that sentence. I am sure that re-reading my post will clear up that difficulty for you.

If you expect me to be able to read your mind, you are sadly misinformed about the nature of my mental abilities. I can only understand what is actually written, not what you assumed when writing it.

I'm sorry if your English isn't very good,

I can assure you that my English is just fine.

but it is not necessary to be a savage to be characterized as having savage behavior. That error almost seems deliberate.

Being someone's enemy does not involve "savage behavior", either. I do not subscribe to the idea that everyone has to pretend being everyone's friend -- I find it to be more honest and even polite to make my position clear and avoid unnecessary confusion. I am not an American. I do not care about anything that distinguishes Americans from the rest of the world. I have witnessed things that directly conradict American version of history. I know that most of Americans' feeling of self-worth and life goals are based on carefully constructed mythology that I am debunking. Obviously I can't expect to be met with anything less than hostility no matter how much I will sugar-coat the truth, so I choose not to do it at all.

Your content is spurious and devoid of anything but self-righteous vitriol.

Actually most of it is historical facts that can be easily verified by checking circumstances of USSR dissolution, economic policies under Brezhnev/Gorbachev/Yeltsin/Putin, declassified documents revealing actual USSR military budget in 80's, etc. Of course, American patriots would rather claim that facts are vitriolic (or, as some American comedian said, reality has bias).

Perhaps you have a problem with only reading what you want to read. Back your assertions. If tens of millions of people agree with you, there should be some indication of that.

If tens of millions experienced high quality of life, it is at least an indication that economy was actually doing well -- you can't turn tens of millions into some kind of shielded privileged class within a country with USSR-style economy. If same tens of millions seen no change at the point when USSR was dissolved, and rapid deterioration of conditions after reforms that were supposed to improve the economy, it's a natural conclusion that USSR dissolution was not caused by any kind of "economic collapse", and subsequent reforms had more to do with 90's crisis than anything USSR-specific.

Probably out of tens of millions you can even find an economist.

As I already established, being a professional economist does not turn a person into instant authority on the subject of economy. What American economists were saying about USSR "collapse" contradicts with evidence.

Hell, you can't even find the "authority figures" you're railing against. Who are you fighting here?

Journalists, economists, politicians, policymakers and writers who planted ideas about "USSR economic collapse", "trickle-down economy", and various implied beliefs of American superiority i

Re:Holy Mackerel!

[Anonymous Coward]

blah blah blah

You're hopeless. I believe that what you say is probably correct, but clearly I've been wasting my time responding.

I wish you good fortune in your quest to---what? Piss off Americans? Educate them to your opinion? There can be nothing wrong with the perspective you are trying to impart, at least. One would just hope---bah. I've said too much already.

yours most sincerely
-T

doh!

[Digitus1337]

Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear.

It's so simple, I wish I'd thought of it!

Re:doh!

[gaspyy]

Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear.

It's so simple, I wish I'd thought of it!

Don't worry, someone probably already has a patent on it.

Re:doh!

[Anonymous Coward]

This idea was invented by Shampoo.

Re:doh!

[Anonymous Coward]

no.. no it wasn't

Re:doh!

[Anonymous Coward]

GOLD! is that Ron Paul I see with the knowing smile?

Re:doh!

[jmerlin]

Gold? Bah. That's so egyptian.

I'd like to be buried in a pyramid with statues carved of me out of antimatter. Finally, I can loot King Tut and make my dream a reality!

Efficiency Considerations

[omnilynx]

I wonder how efficient this process could be made. If it could be done with relative efficiency, would it be worthwhile to start looking at antimatter as a viable energy storage solution for certain applications? As far as I was aware, one of the major roadblocks to that was the antimatter creation process.

Re:Efficiency Considerations

[Kagura]

As far as I was aware, one of the major roadblocks to that was the

Nah, after you defeat the Onett Chief of Police, they open up the roadblock down the path that leads to Twoson.

Re:Efficiency Considerations

[compro01]

If the summery is right about what laser they used and the energy use for such (400J), and the count of the particles (~100 billion), and we were able to capture all energy from the annihilation (E=mc^2), we're looking at about 0.004% efficiency.

We're a looooooooooooooong way from having antimatter as a viable energy storage solution.

Lasers

[Chuck Chunder]

Is there anything they can't do?

Re:Lasers

[superdave80]

It's even more amazing when you consider that when lasers were first developed, no one thought they would have much practical use. They were "A solution looking for a problem."
http://www.press.uchicago.edu/Misc/Chicago/284158_townes.html

Now, try to imagine modern technology without lasers...

Re:Lasers

[Anonymous Coward]

ya, but luckily everything they cant do is covered by nanotubes

Re:Lasers

[Anonymous Coward]

Is there anything they can't do?

Fix Vista?

Re:Lasers

[syousef]

Is there anything they can't do?

Yes, there is! That is what the sharks are for!

Re:Lasers

[Anonymous Coward]

A message from the alternate universe without lasers:

*pops in a cartridge to the video player*. Eh? You guys actually use disks?! How ridiculous, that cartridge happens to have 5TB of space, and contains some ultra-high-def porn. You think you have it bad seeing a zit on a girls bum? Ha, when they show their bums, I can tell how good they wiped their ass!

*shivers*, yes, a world without lasers is truely horrifying. *heads back to his nice, low-def porn stash*, horrifying indeed.

Re:Lasers

[marcosdumay]

Quite impressive, even more when you think that all that comes from the questioning of why do coal shine red when hot...

Re:Lasers

[harry666t]

We still have no anti-sharks to mount these lasers on, so they're pretty useless ATM.

Re:Lasers

[jmerlin]

They can't crystallize dilithium..

wait..

has anyone tried this!?


Perhaps afterwards we can stabilize Omega particles...

Re:Lasers

[invisiblerhino]

The same question applies to sharks.

so does this mean free energy?

[Anonymous Coward]

i've heard ufo conspiracy believers say that when you combine anti-matter and matter you get instant energy.

bob lazar http://www.youtube.com/watch?v=JDwQssm86xo&feature=related

http://www.astro.virginia.edu/~jh8h/glossary/antimatter.htm

Re:so does this mean free energy?

[Xiroth]

No. We will not be able to get energy out of this than it costs to generate the anti-matter. With regards to energy, at best this will be a energy storage device. However, its unique nature may prove useful for various future applications - now that this sort of potential is available, people will start to think about how to use it.

Science Journalism FAIL

[Valacosa]

The anti-matter, also known as positrons...

*Sigh*

I guess the PR agent who wrote the story didn't even read the Wikipedia page on antimatter. Either that, or he/she just isn't a good writer -- that statement implies that all positrons are anti-matter and all anti-matter is positrons. Only the first statement is true.

Re:Science Journalism FAIL

[pavon]

that statement implies that all positrons are anti-matter and all anti-matter is positrons.

Okay, I guess I don't understand anti-matter as well as I thought I did, and reading the link didn't help. So, I'll ask - why is the first half of that statement not true?

Re:Science Journalism FAIL

[Anonymous Coward]

The anti-matter, also known as positrons...

vs.

Anti-matter, also known as positrons...

Teh English lungage be your friends!

Re:Science Journalism FAIL

[Valacosa]

I never took particle, so I can't go into the same depth as some of my friends could. But basically, there's this whole zoo of particles most of which you've heard of. Electrons, protons, etc. Most* of these particles have a corresponding antiparticle. The proton has the antiproton. The neutron has the antineutron. And the electron has the positron. If it helps, you can think of it as the "mirror universe" of the particle zoo -- the antiproton is a proton with an evil streak and a goatee.

Matter is made up of protons, neutrons, and electrons, among other things. By the same token, antimatter is made up of antiprotons, antineutrons, and positrons. The statement "Anti-matter, also known as positrons..." is as ridiculous as the statement "Matter, also known as electrons...". It's either a scientific or grammatical error, and I can't figure out which would bother me more.

Anyway, I hope that helps.

* AFAIK, bosons don't have antiparticle equivalents, only fermions do. But unless you're a physicist or really interested in the subject, don't worry about the distinction between bosons and fermions. I won't help you get laid, that's for sure.

Re:Science Journalism FAIL

[DMUTPeregrine]

The first half is true, as he said. And it doesn't imply that all antimatter is positrons, merely that all antimatter created by this process is positrons.

Re:Science Journalism FAIL

[Anonymous Coward]

i think he means that anti-matter encompass several things while positrons specifics a specific type of antimatter. if i remember correctly, (it's been a while), anti-matter is matter that has the opposite charge then normal; proton having a negative charge and electrons having positive charges. positron probably only refers to one type of them.

Re:Science Journalism FAIL

[Ed_1024]

Does anyone know what happens when two unequal normal and anti- particles meet, e.g. an electron and a positron annihilate to two gammas but what is the result of a positron-proton interaction, for instance? What is 1835/1836ths of a proton (if that's what happens)?

Re:Science Journalism FAIL

[Whiteox]

What a great pick up line: Did you know that bosons don't have antiparticle equivalents, only fermions do?

Someone try that please as I don't get out much.

Re:Science Journalism FAIL

[EdIII]

don't worry about the distinction between bosons and fermions. I won't help you get laid, that's for sure

" iT won't help you get laid, that's for sure"

Sometimes the little things make a huge difference don't they? :)

Re:Science Journalism FAIL

[bloobloo]

Nothing. They would repel each other as they both have positive electric charges.

Re:Science Journalism FAIL

[kmac06]

As the other poster mentioned, they would repel each other, but that's not really the end of the answer. If they could be brought close enough together (which they certainly could), they still wouldn't annihilate, because of conservation laws. For one, charge would not be conserved (two positive charges would disappear). Lepton number conservation (think number of electrons conserved) and baryon number conservation (think number of protons conserved) would also be violated. It's for these same sort of conservation laws that negative electrons don't annihilate with positive protons all the time.

Hot plasma jets!

[Dutchmaan]

The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.'

Apparently, it seems I can create anti-matter from eating too much TacoBell.

Re:Hot plasma jets!

[cpricejones]

WhiteCastle is also an efficient catalyst for dark matter creation. And dare I say more cost efficient?

uhm

[Anonymous Coward]

there goes the galaxy

All or Nothing

[Jheralack]

I always wondered if they could assemble enough anti-matter to perform a Cavendish experiment if it would prove to be repulsive to regular matter gravitationally. I know the current theory doesn't call for it, but hey, that's why we do the experiments. Very symmetrical (in comparison to the electrostatic force equation), and very cool, if it turned out to be true. On the other hand, somebody should stop these fools now. The next thing they will want to do is bottle the stuff, and regular nukes would be toys in comparison.

Re:All or Nothing

[maugle]

Oh, that's a fun thought. On the other hand, I don't really see anyone trying to build an antimatter bomb any time soon, since just keeping one on hand would be incredibly risky:

Something goes wrong storing a nuke: Area sealed off, that particular spot possibly radioactive
Something goes wrong storing an antimatter bomb: Area vaporized, that particular spot the center of a city-sized crater

Re:All or Nothing

[meringuoid]

The next thing they will want to do is bottle the stuff, and regular nukes would be toys in comparison.

Inefficient. Producing antimatter this way still takes more energy than the antimatter releases in annihilation. Where's the benefit? An antimatter bomb would be smaller and lighter than an equivalent hydrogen bomb, but still far more expensive. No form of power generation in the world can come close to the efficiency of a hydrogen bomb.

Work out a miraculous means of making antimatter cheaply, in bulk and with lower energy input than its annihilation yield, and then we'll talk about antimatter bombs.

Re:All or Nothing

[Anaerin]

While a H-Bomb is more efficient, an Antimatter bomb could be expanded over time, collecting a very large quantity of antimatter particles and storing them together over a period of months or years. Think buying one Lego block per hour and slowly building yourself a model of the Eiffel tower, or filling a gas can, rather than taking a stick of TNT or a plaster mould. A H-Bomb is fixed. Once it's constructed, it's 'full', whereas this would enable a "Cache" of antimatter to be built over time and stored until it is needed. Not that I'm encouraging anything like this, of course.

Re:All or Nothing

[Anonymous Coward]

Inefficient. Producing antimatter this way still takes more energy than the antimatter releases in annihilation. Where's the benefit? An antimatter bomb would be smaller and lighter than an equivalent hydrogen bomb, but still far more expensive.

You answer your own question. It would be smaller and lighter, small and light enough to be a huge tactical and strategical benefit in quite a few scenarios, more than enough to outweight the cost. Militaries aren't exactly on the cheap, if you haven't noticed.

Hiroshima in a sniper rifle bullet, anyone? Suitcase bomb in hundred megaton range? Any takers? Thought so.

Wow PET scans anyone?

[Billy the Mountain]

This may open the possibility of cheaper PET scans. Currently, the limitation of PET scans is the answer to this question: "How far away is the nearest Cyclotron?" The half life of the radioactive material used in Positron Emission Tomography, typically Flourine-18, is ~110 minutes. With a laser that can generate positrons, you could have a mobile PET scan unit that would only need to rely on being able to connect to the grid.

BTM

Re:Wow PET scans anyone?

[Atlantis-Rising]

I believe, although I am certainly no expert, that hospitals and places that do PET scans do not take delivery of the radioactive materials with such short half-lives directly; they keep on hand material that will decay into the materials they need, which allows them to keep it on hand for longer.

Re:Wow PET scans anyone?

[krysith]

No, I don't think so. F-18 is usually used as part of FDG (Flourodeoxyglucose), a biologically active molecule, so that the positrons are emitted from where glucose is consumed. Having random positrons flying throughout your body won't make for a very effective PET scan.

Also, wouldn't it be more effective to just use Ga-68 if you are far from a cyclotron? It has a 68 minute half-life and is produced from Ge-68 generators, which have a 271 day half-life. I have a NIST traceable sample of Ge-68/Ga-68 in equilibrium, which we use to calibrate the F-18 dose calibrators,because there is no way to get a NIST calibrated F-18 sample.

Re:Wow PET scans anyone?

[Anonymous Coward]

Incorrect, Sir. Having worked at a PET laboratory I feel the need to correct this.

You're right that PET works by measuring positron/electron annihilation produced gamma rays. But taking a PET image is not like taking an x-ray. The radiation source is not external. PET is a functional imagining method that uses internal radiation. It means that the radioactive stuff is injected into you in fairly large doses.

The positron active isotope, like F-18, is injected into the patient as part of normal molecules like certain hormones. Other isotopes might be used in things like radioactive glucose for example. These chemicals then travel in the bloodstream and rapidly accumulate in certain parts of the body. Where and how strongly they accumulate varies between molecules and the current metabolism levels in the target tissue.

Since the positron decay happens all the time in the molecules, after a short while you have certain parts of the body radiating more positrons than the rest. These positrons annihilate within about a centimeter of the decay spot and produce two gamma rays at a 180 deg angle. Some of these ray pairs can be recorded at the detector ring(s) and using some fancy 3D statistical analysis a picture is created indirectly.

A portable positron source might have other uses, maybe in radiotherapy, but as such it can't be used in PET imaging and I doubt a rather weak positron source could actually create the isotopes in situ either. (not a nuclear physicist but I understood synchrotrons use very energetic protons to create the isotopes.)

Re:Wow PET scans anyone?

[Anonymous Coward]

This may open the possibility of cheaper PET scans. Currently, the limitation of PET scans is the answer to this question: "How far away is the nearest Cyclotron?" The half life of the radioactive material used in Positron Emission Tomography, typically Flourine-18, is ~110 minutes. With a laser that can generate positrons, you could have a mobile PET scan unit that would only need to rely on being able to connect to the grid.

BTM

You are mixing up two parts of a PET scan. The raw materials for a scan are isotopes, such as Fluorine-18. These isotopes are injected into the patient as part of some biologically active molecule, for instance sugar. After a while, the sugar become incorporated into cells, with more sugar in metabolically active cells. The isotopes then decay, releasing a positron. Each positron released will give it's location in the body.

Blindly generating positrons doesn't help PET scans since the location of generation is more important that the quantity of particles.

Re:Wow PET scans anyone?

[Anonymous Coward]

The reason a PET scan works, is not just because positrons are produced in the decay of F-18. It is because the source of the positron is some active site (such as FDG might go to), and the positron doesn't travel far (microns-mm) before it gives rise to the two 511 keV gamma annihilation photons. It is the detection of those 2 photons which allows one to calculate where the FDG was, when the F-18 decayed. This other means of producing positrons isn't going to help that.

Re:Wow PET scans anyone?

[Anonymous Coward]

Except for that pesky gamma radiation. Thanks, but I like my skin color the way it is. I don't look good in green. Trust me, you wouldn't like me when I'm green.

Re:Wow PET scans anyone?

[ceoyoyo]

PET scans do not involve injecting antimatter. The gamma rays produced by the positrons produced by the radiopharmaceutical are detected, yes, but the radiopharmaceutical and it's metabolic properties are what make PET different than an x-ray.

We already have x-ray machines that work quite nicely using electricity.

Reading skills FAIL

[Anonymous Coward]

They said "The anti-matter", so it means the anti-matter that they produced, not anti-matter in general.

interesting implications

[erbbysam]

From what I can gather from the comments and the article, this could become a stable fissionable reaction which would, hypothetically(assuming you can build up and store this stuff) produce an almost unlimited amount of energy? or is the gold(if there are no alternatives)/energy consumptions be too great?

Science Journalism Critique FAIL

[Anonymous Coward]

Either that, or he/she just isn't a good writer -- that statement implies that all positrons are anti-matter and all anti-matter is positrons. Only the first statement is true.

Nice try, but not true. Your argument would be correct if the statement had read "Anti-matter, also know as positrons...", but it does not. Rather the author says "The antimiater, also known as positrons...".

This sentence only refers to the antimatter created during this experiment. And, near as I can tell, positrons are indeed the only form of antimatter produced in the experiment.

The lesson here - don't post smug messages denouncing someones incorrect grammar when their grammar is in fact correct. Check your facts.

Re:Science Journalism Critique FAIL

[windsurfer619]

None the less, the statement still reads as ambiguous with article or without. One can only draw the correct meaning from the statement if you already know "antimatter" and "positrons" aren't equivalent terms.

Er, if you didn't know that, is it really in the reporters place to give a lecture to the reader on anti-matter? I think that tidbit was just for the knowledgeable. I agree with grandparent: you're just arguing for the sake of arguing.

Re:Science Journalism Critique FAIL

[Anonymous Coward]

And your just gay.

Re:Science Journalism Critique FAIL

[Anonymous Coward]

The news item

"Intel unveiled three new processors today. The processors, also known as Intel Core i7, ..."

does not imply that all processors are Intel Core i7. Learn to parse English.

Re:Science Journalism Critique FAIL

[windsurfer619]

Gee, I wonder who that was posting as AC!

Wow!

[Profane MuthaFucka]

I am hoping that they can produce enough anti-matter to make a weapon of some kind. An anti-matter bomb would be many many thousands of times more powerful than even a hydrogen bomb, and it gives me great hope to think that a bomb that huge would make America even safer than thousands of nuclear warheads already make it.

Oh wait, that was just me getting into touch with my inner-Teller.

Re:Wow!

[ravenshrike]

No, an AM bomb would be much more efficient than a thermonuclear device, which is currently the most efficient energy generation system available.

What about gold-nanoparticles instead

[ancient_kings]

of a pinhead? I know making gold nano-particles can be done by anyone, anywhere. It is very simple to do. They are much smaller than a pinhead and their arrangement can easily be made so that the surface area is billions of times larger than a pinhead. Now, can a simple pointer laser set off positrons? If not, how about a green laser? If not, how about shining the green laser through a $600 frequency doubler crystal onto those gold nano-particles?

Re:What about gold-nanoparticles instead

[Patrik_AKA_RedX]

I tried that last summer and I can tell you shouldn't do this. My parents still have a hard time believing they lived there for 12 years and never noticed the 500m wide lake behind the house.

Where's the boom?

[TheBlunderbuss]

Where are the anti matter particles now?
I would think they're touching matter, since they didn't just harmlessly disappear.

Isn't there supposed to be an enormous explosion when matter and anti-matter meet?
Or is that fiction? or friction? Or fission? Or fusion? or confusion?

Re:Where's the boom?

[Boronx]

You just missed it.

Re:Where's the boom?

[SanityInAnarchy]

My understanding is, they probably did harmlessly disappear -- matter/antimatter annihilation turns matter directly into photons. Intuitively, I assumed a positron and an electron will turn into two photons -- Wikipedia confirms that this is what usually happens, though there can be more.

So, billions of particles means probably billions of photons.

Now, Google the number of photons put out by a simple 100-watt light bulb...

The point is, well, look at how many atoms are in a thimble -- and each of those atoms is going to have more than one electron. Take just the electrons in a thimble-full of matter, convert them to antimatter, and you have a much bigger boom.

So, weaponizing this would definitely be more dangerous than weaponizing nukes. I always thought it would look cool to see a planet cracked in half, but I also kind of want to live...

Re:Where's the boom?

[compro01]

You are fantastically overestimating how much they made. 100 billion particles seems like a lot, but it's actually only about 9.1x10^-17 grams (91 attograms). You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.

Re:Where's the boom?

[Anonymous Coward]

People usually stop noticing things when they evaporate into a flash of light.

Re:Where's the boom?

[Anonymous Coward]

E=mc^2

100 billion positrons canceling with 100 billion electrons is 200,000,000,000 * 9.1093826(16)Ã--10â'31 kg = 1.8 * 10^-19 kg

E=(1.8 * 10^-19)*3*10^16

E = 5.5 * 10^-3 J

E = .0055 jewels of energy. Far less then the laser - you might measure it but you aren't going to feel it. As opposed to 1 Joule of energy to lift an orange a meter. Now consider if you made a *gram* of antimatter instead, then you'd get 1.8*10^14 J of energy - or 40 kilotons of TNT, 3 times the yield of the bomb that leveled hiroshima.

In short, it was just really, really small due to the tiny mass of 100 billion positrons.

Re:Where's the boom?

[Anonymous Coward]

You could stand in front of it, but then you'd have no Livermore!

I'll get me coat...

Re:Where's the boom?

[domatic]

I think you mean "Where is the kaboom?!? There was supposed to be a giant Earth-shattering kaboom!"

Re:Where's the boom?

[Mgccl]

confusion caused by Confucius?

Re:Where's the boom?

[kannibul]

"standing right...in the middle of the spray of particles"

Random thoughts:

Might be a bit warm...and tingly.

Dey just makin it rain bro.

Re:Where's the boom?

[compro01]

We're taking about energy levels sufficient to light a 1W lightbulb (one of those tiny christmas tree lights) for about 16 milliseconds, roughly one refresh cycle of an old CRT monitor. If you were pretty close and they all annihilated in a small area all at once, you might see a small blink of light.

Re:Where's the boom?

[Anonymous Coward]

You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.

before or after your face melted?

[captcha was miracles!]

Re:Where's the boom?

[Anonymous Coward]

Well, you would loose 17 grams of weight.
Can they control the anti-matter with some human-friendly field? If so, what about removing unwanted elements (fat? cancer?) with stream of particles?

Re:Where's the boom?

[kwikrick]

You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.

Except you'd also be standing in front of the frickin' laser...

Re:Where's the boom?

[compro01]

Read closer. that's 9.1*10^-17. 0.000000000000000091 grams.

Re:Where's the boom?

[Anonymous Coward]

You are fantastically overestimating how much they made. 100 billion particles seems like a lot, but it's actually only about 9.1x10^-17 grams (91 attograms). You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.

Re:Where's the boom?

[Anonymous Coward]

You are fantastically overestimating how much they made. 100 billion particles seems like a lot, but it's actually only about 9.1x10^-17 grams (91 attograms). You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.

Until you get angry and turn into a green monster from all of the Gamma ray exposure...

Re:Where's the boom?

[Anonymous Coward]

As was already calculated, it's 0.018 J. 1 J is the work needed to move 100g by 1 meter. It would be a noticeable, but minor flash probably.

RHPS

[winphreak]

Why do I find it funny that this just makes the anti-matter laser in Rocky Horror Picture Show somewhat... feasible?

Rediculous.

Re:RHPS

[ichbineinneuben]

Thank you. I had the words anti-matter and laser associated in my mind, but could not remember where I had heard them together. You have solved that mystery. Now, back to designing that shark-mounted laser turret...

LAUNCH VEHICLE?

[Anonymous Coward]

What about powering some kind of heavy-lift launch vehicle, to heft heavy payloads into orbit?

I'd read about research into using nuclear isomers to power scramjets and even long-duration predator-style drones, but the nuclear isomer stuff didn't pan out back then (interestingly, it's now making a comeback, thanks to LLNL)

Anyway, couldn't anti-matter similarly be used to generate the x-rays to heat propellant, or even just an airstream? That could make for a lightweight rocketship. Although you'd probably want it to be unmanned.

Quick question for anyone with the knowledge

[Hojima]

Does anyone know if this might someday lead to antimatter plants? From a special on discovery, I heard that antimatter has a 100% mass to energy conversion, and uranium/plutonium is very expensive to enrich, so using gold for energy wouldn't be too impractical. This would be very exciting research if it does mean cheap energy at that scale with no pollution.

Re:Quick question for anyone with the knowledge

[nebaz]

No. While antimatter may have a 100% mass to energy conversion, it takes more energy to create it than it gives off.

Re:Quick question for anyone with the knowledge

[KasperMeerts]

Sorry,the energy you get from the antimatter, if you can collect every single bit, it still even lower than the energy needed to fire the laser. That's conservation of energy for ya.

Re:Quick question for anyone with the knowledge

[CroDragn]

You can't generate a net positive energy source with antimatter. Best you can hope for is to use the antimatter as a form of energy storage (think battery, fuel, etc). Of course, storage problems make it impractical for nearly every use, so don't expect anti-matter cars... ever. Space travel, however, would greatly benefit from a decent means of generating antimatter, since fuel mass trumps most other concerns in that field and anti-matter provides the most thrust/mass of any theoretical substance.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

dot

Re:Quick question for anyone with the knowledge

[kaizokuace]

One step closer to developing the matter/anti-matter reactor. Star Trek will become reality!

Re:Quick question for anyone with the knowledge

[Pr0xY]

I don't necessarily think you are wrong here, but I have a doubt. The reason why is that you wouldn't necessarily be "gaining" energy if you got more out than you put in, because you are simply releasing the energy of the destroyed mass.

As long as the energy required to create the positrons is less than MC^2 (and I would imagine it would be) since anti-matter/matter has a approximate 100% mass to energy conversion, then there should be a net "gain".

Once again, I don't there energy is being "created" here, but more that the energy of the destroy matter is being released.

Similar to how nuclear bombs can produce many many megatons of explosive power from a small catalyst. That too is just releasing the energy in the mass.

Now, making anywhere near efficient use of this energy in anything besides an explosion (bomb/rockets) is another and very important issue.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Don't you mean less than 2MC^2? Since only 1/2 of the annihilated matter is -anti...

Re:Quick question for anyone with the knowledge

[hvm2hvm]

They created billions of positrons with a high power laser. The antimass(?) of a positron is the mass of an electron or 9.1E-31. Let's round it up and say we have 1E+12 positrons. Combine them with 1E+12 electrons, you get
9.1E-31*2E+12*(3E+8)^2=0.018 J.

Now I'm guessing the laser used is pretty powerful and that it consumes a lot of energy. If we take the specs of the laser linked in the summary, then it used 150J on one pulse which is not the true amount of energy they put into the device (it says it takes 30minutes between pulses at full power). The energy used is thousands or millions of times greater than the energy gained.

Of course, lasers might not be the most energy efficient way of creating antimatter but that doesn't change the fact that if you want to turn m matter into antimatter you will need at least 2*mc^2 energy (at least that's my intuitive guess).

Nuclear devices emit huge amount of energy with relatively small energy inputs because the reaction is selfsustaining, something inside the reaction keeps it alive. What you want is something that destabilizes matter and makes it turn into energy by, say, throwing a special particle at neutrons and/or protons. Turning it into antimatter only to collide it with matter afterwards is just a huge waste of energy.

Re:Quick question for anyone with the knowledge

[hvm2hvm]

Sorry, the result for the energy should be 0.16J not 0.018J.
The rest of the post still stands.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Nuclear devices emit huge amount of energy with relatively small energy inputs because the reaction is selfsustaining, something inside the reaction keeps it alive. What you want is something that destabilizes matter and makes it turn into energy by, say, throwing a special particle at neutrons and/or protons.

Yes, a self sustaining process that annihilates matter is what we relly need!

Re:Quick question for anyone with the knowledge

[ultranova]

You can't generate a net positive energy source with antimatter.

Make hydrogen containers with very thin gold walls - or more likely frozen pellets coated with gold. Bombard the gold with a laser, turning the surface layer into antimatter. Antimatter annihilates with the matter below it and creates an explosion, which heats and compresses the hydrogen, igniting a fusion reaction.

It is, essentially, the equivalent of a fission-initiated fusion, which is proven to work and work well. The difference is that there's no lower bound to the size of an antimatter explosion - even a single electron and positron annihilate - so you can make the explosion be of suitable size for a power plant. And of course annihilation, as the name implies, doesn't leave behind radioactive materials, just gamma rays.

Besides, Laser Antimatter Fusion is pretty much the epitome of cool ;).

Re:Quick question for anyone with the knowledge

[Gromius]

You produce anti-matter in anti-matter-matter pairs. Ergo your idea can not work.

I spent a while thinking if you could exploit the W boson which produces anti-matter - matter pairs of different flavour but I couldnt think of a way. Regardless any way which somebody could come up with would give such a small theoretical energy gain that you would almost certainly lose it through efficiency loses.

Re:Quick question for anyone with the knowledge

[marcosdumay]

"The antimass(?) of a positron..."

Anti-matter has mass, ordinary mass, just like matter.

Re:Quick question for anyone with the knowledge

[sdpuppy]

Yes, this experiment accomplished - converting energy into antimatter

The point is having the ability to produce lots of these particles in a directed manner, capture and store them for further study.

Previously the main source for antimatter was certain types of radioactive decay and nuclear reactions.

(example: if you go to the hospital for PET imaging - they inject you with radioactive material that decays by emitting anti-electrons = positrons)

If you want something that could potentially produce energy, this is not it - although in studying the process and the particles we might eventually learn how to produce antimatter more efficiently (to store energy) or perhaps even with net gain by inducing some sort of nuclear reaction.

Re:Quick question for anyone with the knowledge

[entgod]

Even if it wouldn't be possible to use as "free energy", think about think about the possibilities of antimater in some sort of power cell. I hear antimatter has a pretty good mass/energy ratio :)

Re:Quick question for anyone with the knowledge

[Mattsson]

Even if the energy to covert matter into anti-matter is more than we get out in the reverse process, it might be a very high-density way of storing energy for later use.

Re:Quick question for anyone with the knowledge

[entgod]

I know you're trying to be funny but that's exactly what the fission reaction used in power plants is. That's why we get more energy out of it than what we have to put into it.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

You mean it CURRENTLY takes more energy to create it than it gives off.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Of course, lasers might not be the most energy efficient way of creating antimatter but that doesn't change the fact that if you want to turn m matter into antimatter you will need at least 2*mc^2 energy (at least that's my intuitive guess).

According to my intuition, your intuition is in error. Even if we're creating the antimatter from whole cloth we would be spending:

mc^2 + processing inefficiencies

But during the annihilation, a matter particle is also annihilated producing:

2 mc^2 - processing inefficiencies

Thus, the total released energy is something along the lines of:

mc^2 - 2 * processing inefficiencies

Whether or not we can develop a process where the second part of the equation doesn't dominate (that doesn't go on to level the city) is the real question.

Re:Quick question for anyone with the knowledge

[Kugala]

With fission we get the Uranium/Plutonium out of the ground, it costs us only a small amount of energy to get relative to what it produces in a power plant. With anti-matter, it costs just as much to create it as it produces, plus overhead etc. It'll never produce energy. However, as an above poster pointed out, it's the most efficient energy storage device we're aware of, so there's potential for cars to space vehicles.

Re:Quick question for anyone with the knowledge

[david.given]

As long as the energy required to create the positrons is less than MC^2 (and I would imagine it would be) since anti-matter/matter has a approximate 100% mass to energy conversion, then there should be a net "gain".

Alas no. Antimatter is made from scratch, from pure energy. The laws of physics forbid the conversion of normal matter into antimatter. So not only do you have to feed in MC^2, you also have to do it in an incredibly inefficient way, because squeezing enough energy into a small enough space to 'condense' into matter is really, really hard.

Re:Quick question for anyone with the knowledge

[mattcasters]

Interesting, a cool laser ignition driven antimatter fusion combustion engine.

Re:Quick question for anyone with the knowledge

[FTWinston]

The only difference is that the quarks have opposite charge.

Re:Quick question for anyone with the knowledge

[VoidCrow]

That doesn't stop it being incredibly useful (and incredibly dangerous). And, if you can place your antimatter plants nearer the *Sun*...

Re:Quick question for anyone with the knowledge

[VoidCrow]

Can I have your babies? Or vice versa? Either would be cool.

Re:Quick question for anyone with the knowledge

[SolusSD]

lets clear this up-- antimatter is _not_ theoretical. It is real, as real as normal matter. I heard it referred to as a theoretical substance as recently as this year to TV.

Re:Quick question for anyone with the knowledge

[technomom]

....and iPods, which will then be known as "antiPods".

Re:Quick question for anyone with the knowledge

[cbiltcliffe]

so there's potential for cars

Are you sure you want the current crop of moronic drivers running around with even a tiny amount of anti-matter in their cars? Hell. That'll make the current flaming wrecks seem like a walk in the park.

Could you imagine this:
http://www.youtube.com/watch?v=LyCP97a-fTI
(need to sign in, as it's rated mature)
being considered a minor accident?

Re:Quick question for anyone with the knowledge

[d3ac0n]

Heh, that's what I was thinking.

"Forget all this crazy theoretical crap. When do I get my Warp Drive damn it?!"

Re:Quick question for anyone with the knowledge

[Lord Ender]

Our energy problems are solved! We've invented a generator that doesn't use expensive fossil fuels at all! It just uses gold!

Re:Quick question for anyone with the knowledge

[rubycodez]

inertial confinement fusion with deuterium pellets surrounded by gold has already been done, but antimatter isn't a significant part of the fusion process. Even in this article, the amount of antimatter produced is miniscule

Re:Quick question for anyone with the knowledge

[Jonny_eh]

But wouldn't you actually release the energy when the anti-matter and matter is recombined? This would release the combined energy of both types of matter.

It'd be great if someone more knowledgeable than me can explain how anti-matter can be turned into energy.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Does anyone know if this might someday lead to antimatter plants?

You mean like a venus fly trap?

Re:Quick question for anyone with the knowledge

[AchilleTalon]

Mod parent up. The whole point here is exactly what he said. Producing a huge amount of anti-particles for further study, experiments, injection beams into colliding devices, etc.

Re:Quick question for anyone with the knowledge

[squoozer]

Antimatter is the new hydrogen. Always mistaken for an energy source but once the containment issues are fixed a really good energy store.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

I know you're trying to be smart, but that's what GP was referring to.

Re:Quick question for anyone with the knowledge

[PeeAitchPee]

And of course annihilation, as the name implies, doesn't leave behind radioactive materials, just gamma rays.

Oh, good.

Re:Quick question for anyone with the knowledge

[Elladan]

I heard on TV that an omnipotent sky monkey plans to torture us all in a volcano forever because some woman made out of a guy's rib ate a snack with a talking snake.

And that was supposed to be an education show!

Re:Quick question for anyone with the knowledge

[gadget junkie]

They created billions of positrons with a high power laser.[...]

Why create Billions when you can create....... Millions???

Re:Quick question for anyone with the knowledge

[Lord Apathy]

The laws of physics forbid the conversion of normal matter into antimatter

Can you quote what law forbids this? I don't doubt you but my brain is vacationing in Bermudan this week, sent me a post card and everything "Glad your not here.." Anyway I'm just a little fuzzy today.

Re:Quick question for anyone with the knowledge

[Retric]

If I am not mistaken this produces both particles and anti particles at the same time. Also if you using antimatter to generate heat to make electricity your only got to be ~40% efficient so it would still be a net loss.

Re:Quick question for anyone with the knowledge

[CroDragn]

Didn't mean to imply antimatter was just theoretical, just that there are other theoretical matter types out there and antimatter trumps 'em in terms of energy storage.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Can you quote what law forbids this? I don't doubt you but my brain is vacationing in Bermudan this week, sent me a post card and everything "Glad your not here.." Anyway I'm just a little fuzzy today.

It was the 15th commandment, but Moses acidentally dropped it:

15. Thou shalt not produce antimatter from matter.

Re:Quick question for anyone with the knowledge

[hvm2hvm]

"mc^2+processing inefficiencies"
Yes, that seems more accurate. I was thinking it wrong there. Now if we can get the energy out/in ratio above 50% of mc^2 this would create huge amounts of energy.

Re:Quick question for anyone with the knowledge

[Deadplant]

You need to channel the matter and anti-matter streams through dilithium crystals.

I think you need to use anti-hydrogen though, not just anti-electrons.

Re:Quick question for anyone with the knowledge

[Deadplant]

uranium is costly to enrich but the hard work of creating the uranium atoms was done for us by the sun a long time ago.
There is no (known) similar reservoir of anti-matter available to us. We have to create any anti-matter from regular matter using the full++ required energy. There is no pool of energy to draw from; any pool of energy would have to be filled by us and therefore pointless.

Re:Quick question for anyone with the knowledge

[Deadplant]

doesn't leave behind radioactive materials, just gamma rays."

lolz, *just* gamma rays.

Re:Quick question for anyone with the knowledge

[Doc Ruby]

It shouldn't necessarily take more energy to split matter, like these gold particles, into antimatter and matter components, than the total energy equivalent of the original matter target. When the mutual annihilation is finished, the matter+antimatter mass is "gone", not reconverted to the original matter.

Conversion to antimatter before mutual annihilation might be the intermediary step that makes controlled, small scale 100% matter/energy conversion practical.

Re:Quick question for anyone with the knowledge

[Doc Ruby]

Actually, the GP is correct about this experiment. I see now that the experiment didn't convert the gold target to matter and antimatter, but rather used the gold target (without consuming it) to convert the laser to energy, which decayed into matter and antimatter. So the energy in the antimatter's mass is indeed less than was in the laser, as was the energy in the resulting matter, the sum of which was still less than (or perhaps equal to) the energy in the incoming laser. No laser is 100.0% efficient, so the energy to make the laser beam is greater than the energy recoverable in the matter+antimatter reconversion back to energy. And of course making the rest of the apparatus consumes energy not recovered, too.

Re:Quick question for anyone with the knowledge

[Frnknstn]

Taking that further: 'processing inefficiencies' are likely to relative to the amount of mass you produce. This means your final equation:

gain = (mc^2) - (m * inefficiency constant)
  = m( c^2 - inefficiency constant )

So, as long as we us less than about 44937758900000000000 joules of energy to make a kilogram of antimatter, store it, transport it, annihilate it and harvest the resultant energy, it's all gravy.

Re:Quick question for anyone with the knowledge

[Roger W Moore]

uranium is costly to enrich but the hard work of creating the uranium atoms was done for us by the sun a long time ago.

Not quite. It was done by a star which preceded the sun and which went supernova about 6 billion years ago.

Re:Quick question for anyone with the knowledge

[Kugala]

Well, assuming the amount of energy required to move a car around doesn't change signficantly, and you still had a range of about the same, the total amount of energy stored in fuel wouldn't change either.

Of course, they probably will get higher, and there's a decent market for vehicles with thousand plus mile ranges I'd imagine (Trucks specifically).

Then again, gas tanks really don't explode or even catch fire currently...so it's possible to design a safe system.

I'm personally more worried about the possibility of flying cars. This morning 2 people pulled in front of me without looking...and we expect them to navigate in 3 dimensions?

Re:Quick question for anyone with the knowledge

[Deadplant]

I stand corrected.

Re:Quick question for anyone with the knowledge

[nsteinme]

You might be too quick to assume that anti-matter cars will never exist, trivial as this speculation is.

Imagine someone in the railroad era of the 1800s thinking, "Surely there will never exist horseless carriages powered by fossil fuels. It is not practical." While today it is certainly prohibitively expensive, if not impossible, to practically store antimatter in the equivalent of a gas tank of a vehicle, this speaks nothing of the possibility of future practicality.

Re:Quick question for anyone with the knowledge

[Liath]

There's something disturbingly hilarious about "deadplant" laughing at gamma rays

Re:Quick question for anyone with the knowledge

[danieltdp]

Its the quantum numbers that get switched. And mass is no such a thing

Re:Quick question for anyone with the knowledge

[Tranzboy]

I don't think it would work quite as easily as you've outlined. For instance, let us consider the frozen bits of Hydrogen. How will you coat them with gold? Assuming you could, when you shot the pellet with a laser, why wouldn't the laser+mAm reaction just blow the pellet apart without initiating fusion?

Re:Quick question for anyone with the knowledge

[severoon]

Wow...reading this thread makes me a bit sad, and I can only hope that all the participants in this conversation up to now were not exclusively schooled in the US. (Sadly, I suspect it is so.)

Physics is the study of manifestations and transformations of energy. One of the basic laws of physics is that energy is conserved. If you pump so many GeV of energy in the form of coherent radiation into gold atoms, it seems from this article that some fraction of that energy is converted into positrons. When those positrons collide with electrons in equal numbers (as they're sure to do in this universe given even a very short period of time), the matter-antimatter pair annihilate each other and mass is converted back to radiation energy.

The amount of energy released in this annihilation is equal to the amount used to create the positrons in the first place, which is necessarily less than the energy of the laser light incident on the gold atoms. Some of that incident light is going to be lost knocking electrons off, knocking gold atoms out, heating the gold, getting absorbed and re-emitted as a different frequency of light, etc. We've only been looking at the actual point of energy transformation, too...if we go even further back in the chain, we have to look into the efficiency of the laser itself. Certainly less than 100% of the energy consumed by the device is emitted as a coherent light beam even before we look at how this beam is interacting with the gold.

So, by definition, antimatter cannot be a first energy source in this universe. Antimatter could be useful as a means of storing a large amount of energy, but not as an ultimate source. (Unless we find a naturally occurring, ready source of antimatter that we can harvest, which would probably require a wormhole to an alternate universe and a means of controlling that wormhole. Uh oh, queue up the Star Trek / Stargate SG-1 nerds...)

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

that may change soon. 100 billion particles verses the head of a pin. head of a pin is probably about one to five grams.

9.10938188 Ã-- 10-22 kilograms of antimatter were produced.

now that will react with the same amount of matter.

this yields a total of 1.82187638 Ã-- 10-21 kg of reactant.

Plug in E=MC^2

E = 1.82187638 Ã-- 10^-21 * 8.98755179 Ã-- 10^16 m^2/s^2

E = 0.000163742083 kg m^2 / s^2

now this was just the energy release of a billion positrons interacting with normal matter.

as the mass increases, the energy increases at an incredible rate.

if they produced one gram of antimatter, through another series of breakthroughs taking ten years, it would equal the destructive power many times greater than hiroshima.

they key is for the energy required by the laser to be less than the energy output, which will eventually occur as mass increases.

the reason this doesn't violate any laws of physics is that it took the mass (or energy) of the head of a pin of gold in order to create the billion positrons. thus the reaction was massively inefficient. however, with enough scale, that inefficiency could solve world energy problems (and maybe life problems aka death) if we don't run out of gold on the planet.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

from other comments, we might need some clarification here...

was the gold partially converted, aka the billions of particles were emitted from the gold resulting in the gold being billions of particles light?

or did the gold convert the energy into antimatter.

if the gold converted the laser energy into antimatter then yes this is an inefficient process.

if the gold itself was converted into antimatter, causing electrons to change their structure somehow, then this might be a scalable solution.

based on the complexity required, it looks like it's the previous...

but that should be made clear in the article which I did not see.

Re:Quick question for anyone with the knowledge

[kurzweilfreak]

Just don't make him angry, you wouldn't like him when he's angry...

Re:Quick question for anyone with the knowledge

[isorox]

Does anyone know if this might someday lead to antimatter plants?

Like Triffids?

Re:Quick question for anyone with the knowledge

[cbiltcliffe]

No, the amount of energy in a "fillup" won't change significantly, but if a gas tank catches on fire, it will burn slowly over time, due to not being able to get enough oxygen.

If an antimatter fuel system ruptured, you'd have a pretty much instantaneous "burning" of all the fuel in the car. I'm guessing there'd be quite a few road craters that would need to be repaired.

Re:Quick question for anyone with the knowledge

[LrdDimwit]

But where do the sharks come into the equation? I think it would work better if you used shark / antishark annihilation.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Assuming the positrons could be created with less than MC^2, we would never be able to utilize all of that energy, no matter how good we are. No machine can be 100% efficient.

Re:Quick question for anyone with the knowledge

[mog007]

Assuming you're talking about burning Hydrogen with Oxygen to make water, containment is a non-issue. The biggest issue with the Hydrogen economy is actually getting the Hydrogen, it's not easy.

Now, if you're talking about containment for fusion, well that's a totally different thing.

Re:Quick question for anyone with the knowledge

[sjs132]

Can I have your babies? Or vice versa? Either would be cool.

Sorry, No. My wife would wonder where they went to... Could I offer you a Cat?

Re:Quick question for anyone with the knowledge

[sjs132]

Yes! I'm gonna buy all the gold I can and corner the next energy market!

Re:Quick question for anyone with the knowledge

[VoidCrow]

Sure... got any sardines?

Re:Quick question for anyone with the knowledge

[AJWM]

I ask the same question.

For any given particle, you have a problem in that converting it to antimatter violates conservation of electric charge (and spin?), but physics will occasionally let you fudge stuff like that if you do something else at the same time to get net conservation. Since a neutron has both charges, it should be "easy" to convert it to an antineutron (okay, you're converting three quarks to their antiquarks). Aka "reversing the polarity of the neutron flow" ;-)

Mind, being net chargeless, anti-neutrons are tricky beasts to do anything with, it's not like you can contain them in electric or magnetic fields.

Re:Quick question for anyone with the knowledge

[Pr0xY]

You are probably right, so I'm not asking this out of disagreement, but more curiosity.

Isn't the energy emitted going to be from the annihilation of *both* the matter and anti-matter?

So since the reaction only requires that you expend energy in creating the anti-matter. (I know there is overhead and inefficiencies but i'm simplifying for discussion sake).

In the end, we've gotten the energy from 2 * MC^2, but only payed for MC^2. Since ordinary matter is abundant and a natural resource (your requirement for it being a first energy source).

So, my question really boils down to can't the *regular* matter be first source and the anti-matter simply be what releases this energy?

you say: "The amount of energy released in this annihilation is equal to the amount used to create the positrons in the first place." Why isn't it equal to 2x the mass (both matter and anti-matter)?

Maybe I'm missing something.

Re:Quick question for anyone with the knowledge

[Pr0xY]

Ah wikipedia clarified it for me:

"Known methods of producing antimatter from energy also produce an equal amount of normal matter, so the theoretical limit is that half of the input energy is converted to antimatter. Counterbalancing this, when antimatter annihilates with ordinary matter, energy equal to twice the mass of the antimatter is liberatedâ"so energy storage in the form of antimatter could (in theory) be 100% efficient."

So it seems that since creating anti-matter also creates matter, you are only getting half of what you "paid" for in anti-matter back. Thus when you use it to annihilate regular matter, there is nothing to gain since you put in 2x the energy for the mass of anti-matter you got.

Re:Quick question for anyone with the knowledge

[RockDoctor]

As long as the energy required to create the positrons is less than MC^2 (and I would imagine it would be) since anti-matter/matter has a approximate 100% mass to energy conversion, then there should be a net "gain".

Why would you imagine that it takes less than "mc^2" (for m = mass of an electron-positron pair and 'c' standing for the speed of light in a vacuum, both in appropriate units) of energy to produce an electron-positron pair ?

Similar to how nuclear bombs can produce many many megatons of explosive power from a small catalyst. That too is just releasing the energy in the mass.

You're comparing apples and oranges. Or perhaps a better simile, considering previous plantings of space craft into sub-surface Martian orbits, would be that you're comparing newton-metres and lbf-ft, and that (like NASA), you're getting the conversion wrong.

The "megatons" of explosive energy release of a strategic nuke does not refer to the weight of the bomb (how could it be launched, or even carried in a bomber plane?), but to the amount of TNT (or another conventional chemical high-explosive, RDX perhaps) needed to produce the same energy release. That energy release is actually generated by the release of binding energy from converting around 1kg of hydrogen to around 0.96kg of helium.

If you wanted to convert that helium back into hydrogen, you'd have to power your device with the energy produced by exploding some megatons of high explosive (assuming that your energy conversion equipment is perfectly efficient).

IIRC, weight-for-weight you get less energy released from TNT than you do from burning the same weight of sucrose (table sugar) ; but you get the energy released more slowly.
(I haven't done the sums - I suspect that there's a cheat here arising from the fact that the TNT contains it's oxygen for combustion inside the molecule, while in the sugar case you're adding atmospheric oxygen. But I'd have to dig out the chemical tables, which i'm not going to do at this time of the morning.)

Re:Quick question for anyone with the knowledge

[severoon]

Exactly—though the main point of my response above was to make the point that the specific mechanics of how the process unfolds is irrelevant because a thermodynamic maxim must be adhered to: conservation of energy. (Actually, since Einstein, we know that mass is a form of energy, so conservation of mass-energy.)

It's useful to go into the details of energy state transformations only insofar as one would want to understand the process...but this isn't necessary to answer the question I was addressing. To understand whether a process will release energy for human use is fairly simple from the thermodynamic standpoint—all you have to do is calculate the total potential energy of the constituents at the beginning, and then calculate the total potential energy of the constituents at the end. If the sum of potential energy in the end state is less than the amount in the beginning constituents, the process is overall exothermic and can theoretically produce usable energy for human use (actually getting it is a different story...at least one reaction pathway from reactants to products must exist and that pathway must not release too much of the energy in unusable ways).

If you consider gas, for example, it has high potential energy. Adding a bit of energy in the form of a spark, in the presence of oxygen, provides a reaction pathway for the gas to react and form CO2, H20, CO, and a variety of other products. The sum of potential energies of the products is much lower than the initial reactants, gas & O2, so it's a net exothermic reaction and is useful.

Now that gas prices are high, you'll see scam sites that try to sell you the idea of increasing mileage using only water and no other additional energy source. One need not understand the proposed technology if you know basic thermodynamics, however, because water is an extremely low energy compound. Barring nuclear reactions, water is a product of reactions, not a reactant, because of this. Next time a child asks you why it's impossible to burn water, you'll have a ready answer: It's already been burnt. Sites selling a water-fuelled car technology typically try to confuse victims by discussing oxyhydrogen torches, or "water torches". These torches work by using electricity to electrolyze water—that is, split H2O into H2 and O2—and then burn the resulting gases to make a high-temperature flame. In these applications, though, H2O is an energy sink, not an energy source. The ultimate source of energy is vast amounts of electricity, which represents a lot more energy put in than comes out in the form of heat at the end of the process.

Re:Quick question for anyone with the knowledge

[Doc Ruby]

Actually, this experiment didn't convert matter into antimatter. It used matter (the gold target and a source of electrons ionized by the laser driven into the target) as a transducer of laser energy into quanta emitted by resonating electrons after they "interacted" with the gold nuclei. Those final energy quanta decayed into matter and antimatter. The antimatter included the positrons. The gold target and the electrons driven into it also remained with their mass quantity intact. The positrons' mass started life in this experiment as energy powering the laser.

Evidently that procedure is revolutionary in its positron generating efficiency, better than the usual radioactive sodium pathway (used in PET) that actually does convert matter into antimatter.

This kind of laser driven technique cannot produce a net energy gain on output, because no mass is converted to energy. However, it could efficiently store lots of energy in matter-antimatter pairs stored for later annihilation at 100% efficiency. The current procedure is very inefficient, possibly 10 million times (or more) the energy consumed by the 1.25 PW laser (producing 400 joules for 400 femtoseconds) than the energy available from the "billions" of positrons annihilable with an equal number of electrons (or their equivalent mass). But if the inefficiency comes from blasting the gold target with energized electrons that mostly miss the gold nuclei, wasting most of them, and the electron beam could be focused directly onto the nuclei, the efficiency could increase dramatically. Gold's nuclear radius is about 6.3pm, while its covalent radius is about 144pm. So over 500x the electrons are generated than are actually used interacting with the nucleus. If the laser must drive 0.2% the electrons, it might not need to be as high powered (and newly invented), so perhaps a couple terawatts laser rather than a petawatt laser might be required, which could be much more efficient. There is very likely a similar kind of efficiency to be gained if the laser energy conversion to the electrons' kinetic energy also misses most of the electrons, so laser power could be much lower if it's used to accelerate more electrons. If that phase of the reaction were also about only 0.2% efficient, then the overall inefficiency might drop from 10 million to only about 40x (2.5% efficient), ignoring the efficiency of powering the laser to start with. There are even fewer details in the LANL PR about the "interaction" of the electrons with the gold nuclei that causes the electrons to emit the correct quanta to decay into the matter+antimatter than has based these extrapolations on vague info, but if that newly discovered process can be improved in efficiency by close to the "missing" 40x, then the only inefficiency left is powering the laser. Nanoscale devices might achieve all these efficiency gains, possibly manufactured in large quantities at low cost. Which would produce highly efficient energy storage in antimatter form.

A long series of improbably "ifs". But hypothetically those are the parameters that could be tweaked to harness this reaction for practical value.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

Not quite. It was done by a star which preceded the sun and which went supernova about 6 billion years ago.

You make it sound as if there was a single star in the very same place now occupied by Sun that went supernova and left a nice huge cloud of heavy materials that makes up everything there is to the solar system now - that's very unlikely to be the case.

Really it was done by all the stars that ever went boom, each slowly enriching the gas cloud that eventually ended up as the Sun, the Earth, and all the rest of the assorted rubble.

Re:Quick question for anyone with the knowledge

[Anonymous Coward]

That's not "self-sustaining". Your parent was referring to a theoretical conversion of matter to antimatter that released more energy than is needed to do that conversion. With fission, you're limited to the few heavy elements that have a natural tendency to split, with the said antimatter reaction, you could run around turning half of everything in sight to antimatter and subsequently annihilate it with the other half, eventually turning all the mass in the entire universe into pure energy.

Re:Quick question for anyone with the knowledge

[Roger W Moore]

Supernovae produce U-238 and U-235 (I may have got the mass numbers slightly off) in roughly equal quantities. If we measure the relative abundance of these elements on Earth then we can see that they were produced roughly 6 billion years ago.

Of course there would very likely be material from other sources as well, not just that one particular star going bang but since the Earth is at least 4.5 billion years old the sun must be slightly older it is hard to imagine multiple supernovae contributing over time because that would some earlier than 6 billion years ago. You could, of course, have several supernovae all occurring at roughly the same time I suppose but, whether it was one or more stars going bang we do have some evidence that at least one of those stars went bang roughly 6 billion years ago.

Yeah, but

[wicka]

Does this really matter?

Kaboom?

[BriggsBU]

To quote my favorite Martian...

"Where was the kaboom? There was supposed to be an earth shattering kaboom!"

Mod parent up

[shrikel]

Yeah. Now just imagine a nanotube laser! That's probably what modified photon torpedos are made out of.

Re:Mod parent up

[Anonymous Coward]

done. Seriously, too lazy to dig up the reference, but nanotube laser arrays are already at least a decade old.

Its time

[gmuslera]

Intel should use those lasers to start to make processors that use positrons instead of electrons. Robots based on those positronic "brains" will have a big potential, and could last eons.

Re:Its time

[FooAtWFU]

That sounds dangerous. I, for one, am not willing to welcome our new robotic overlords! (Or regular human overlords with robot armies). Intel would need to come up with a scheme to keep the robots from harming people. Some sort of set of axioms... rules... laws, even... that would apply to all the robots they made, in order to keep them in line. Otherwise it would never work.

Re:Its time

[Anonymous Coward]

Easy fixed-see

http://www.dilbert.com/strips/comic/2008-11-14/

iDebt

[Tablizer]

Shoot a laser at the 700b bailout money, and see if a surplus appears.
       

flupbucket

[Anonymous Coward]

Sounds as legitimate as cold fusion. Remember that one?

Oblig...

[elthicko]

I for one welcome our new laser wielding, positron emitting, anti-matter overlords

Great heavens, that's a laser!

[Anonymous Coward]

Yes, Dr. Scott, a laser capable of emitting a beam of pure anti-matter!

Russia

[copponex]

Russia did not invade Vietnam. The United States invaded Vietnam because it is an historically paranoid state, and feared that communism would takeover east Asia were the grass roots movements of communists not exterminated. Similarly today, we're fighting them "over there" instead of "over here." It's just the manufacture of an enemy image that every government uses to maintain power.

Hell, when it comes down to it, why not let the Cubans take over Florida. After all if you stop them there's a risk of nuclear war.

Are you really afraid of the Cuban army? Really?

The Russians placed those missiles in Cuba because we placed missiles very close to their own borders. They made the mistake of thinking that it was okay to follow our lead.

And people in Florida would much rather live in peace under communism than die in a war.

What if you were right? Would you let any democratic principles get in the way of your own abject idealism?

Once the commies take over there will be peace.

Oh no! The commies! The reds, pinkos, the socialists! Run for your lives! Seriously. Only an insane person can turn cowardice into a call to arms.

After all, absolutely no one died in Russia or China or Cambodia after the Communist victory when they decided to get rid of their enemies.

And how many slaves and Native Americans did we kill in the last 200 years when we wanted to get rid of them? How many Vietnamese died before 1975 and after? How many dictatorships have we sponsored with our money and military technology?

You may not think there is blood on our hands, but we have plenty. I know you desperately want to get to the death toll numbers in your rebuttal, but imperialism and colonialism still take the cake for human misery. And if you don't think that America is an imperial empire... well. We have 700 military bases in almost every country of the world, and outspend the rest of the world in military expenditures. What else could I say.

Re:Russia

[Hal_Porter]

Communism killed tens of millions of people. I'd say that was worth fighting against, and worth helping allies against. Even South Vietnam.

Actually I'm typing this from Taiwan now. Back when Taiwan got military aid it was just a nasty a dictatorship as South Vietnam was. So was South Korea. Now both Taiwan and South Korea are democracies whereas China and North Korea have both lost tens of millions (up to 80 million in the PRC) to hunger and to political repression that still continues to this day. If the South Vietnam had survived there is no reason at all that it would not currently be as rich and as free as South Korea or Taiwan.

And if you were living under Communism, you'd have died in a concentration camp for whining about the government the way you obviously enjoy doing.

Re:Russia

[EdIII]

America is an imperial empire

Just remember one very fucking important point in that statement of yours..... Americans ARE NOT PART OF IT. It is the elite and corporate interests that *own* America and it's citizens that act in such a way.

American citizens are just another colony of oppressed people that belong to this "American Imperial Empire" that you speak of. Americans in general have no interests in controlling the rest of the world militarily or economically. Most citizens are far more concerned about the distractions like American Idol, Heroes, Paris Hilton, and Cheeseburgers loaded with chemical crap and zero nutrients. Those of us that tend to concern ourselves with the bigger picture and are consigned to the hell of having a modicum of intelligence are not interested in this Imperial Empire either. I don't mean that as arrogant as it sounds either.

It takes a special kind of person with certain traits and dispositions to cruelly exploit another race of people for their own gain. The average American does not possess those traits and *does not* understand, or perversely enjoy the fact, that buying certain products often helps perpetuate such exploitation in other parts of the world.

And how many slaves and Native Americans did we kill in the last 200 years when we wanted to get rid of them?

Once again, WHO wanted to get rid of them? The average person in those times simply lacked the ability to relate to Native Americans and come to an understanding. The greatest atrocities did not occur from regular people, but from our very own government, corporate interests, and military.

You might as well be saying that all the Chinese workers that participated in building the Great Wall of China actually *wanted* to build it in the first place!

Re:Russia

[meringuoid]

American citizens are just another colony of oppressed people that belong to this "American Imperial Empire" that you speak of. Americans in general have no interests in controlling the rest of the world militarily or economically. Most citizens are far more concerned about the distractions like American Idol, Heroes, Paris Hilton, and Cheeseburgers loaded with chemical crap and zero nutrients.

If America were a military dictatorship this might be a legitimate excuse. However, it is not; it is a representative democracy. Why do you not simply vote out the imperialists? Oh, wait: because the imperialists keep the cheeseburgers coming. Then the masses do support the imperialists, through their very apathy. Otherwise their cheeseburgers might become rather more scarce, their car might become smaller, and their clothes far more expensive for want of child slave labour.

Re:Russia

[OrangeTide]

Bingo. Business is grand and all. But business has a majority control over the political system in the US. And unfortunately for the world, it's not even the right kind of businesses in charge.

We basically elect representatives every election so they can be bribed, mislead or politically neutered to feed an engine that discards the free market in favor of an oligarchy of corporations and special interests.

Bring back free market capitalism (if it ever really existed in the US), and make sure our politicians represents the interests of the people as our constitution seems to imply.

Re:Russia

[damburger]

Global capitalism kills around 10 million per year, who die of hunger in a world with enough food production to feed everyone. This dwarfs even the politically motivated, inflated death tolls for 'communism' that you use to justify any excess of capitalism.

Re:Russia

[EdIII]

it is a representative democracy

LOL!!! ROFL!! I laughed so hard my drink came out my nose!

Representative Democracy? In what possibly way could you misconstrue that? The ruling elite (Elites, Politicians, Corporations, Military Industrial Complex) pass laws ALL THE TIME that no American wants.

The fact that a small percentage of us voted was just the decision being made between a Douche and a Turd Sandwich. Senators and Congressmen create and pass laws and funding measures all the time that only benefit the corporations.

Who really wanted the Patriot Act? My god, if you press me I can come up with at least 100 (no exaggeration) acts of congress that are appalling, and offensive to the average American.

No Sir! Politics in America DOES not represent the interests of the American People, and when it *appears* to do so, it is only because it furthers the goals of those in power to keep them in power.

LOL.

Citizen participation in politics only occurs when they are under the illusion (delusion really) that they have any meaningful effect on the outcome. You want to have a real meaningful effect? Sink 100 million dollars into a lobbying firm and hope your "bribe" money is better than the competitions.

Re:Russia

[Hal_Porter]

The vast numbers of deaths due to Communism are well documented

http://en.wikipedia.org/wiki/Great_Leap_Forward#Consequences
http://en.wikipedia.org/wiki/Holodomor#Death_toll

The problem for people like you is that these happened in areas that the Communists controlled, and directly because of government policies. If there had been no government at all and peasants had lived as they had before (i.e. in a capitalist system) they would most likely have been able to feed themselves. It was an attempt to turn people in serf labouring on collective farms that caused starvation on a massive scale.

Starving people in the third world hardly live under capitalism - the Ethiopian famine occured in rebel areas of a country controlled by a Marxist government.

If you just let people organise themselves, farmers will grow stuff and sell it to make money. Efficient businesses will take over inefficient ones. Quite quickly you'll have a problem of too much productive capacity (the EU pays people to not produce to keep prices high), rather than famine.

Capitalism works. Communism leads to slavery and mass starvation.

Re:Russia

[meringuoid]

You want to have a real meaningful effect? Sink 100 million dollars into a lobbying firm and hope your "bribe" money is better than the competitions.

If you have $100m to spare, form a political party, and then vote for it. The ruling elite are only a ruling elite because people keep voting for them. Stop doing that. If the masses in America really oppose the imperialists, then they can form a new party of their own and kick the imperialists out. That they do not do so indicates to me that the Americans do in fact support the imperialists, because that means the cheap cheeseburgers keep coming.

Admittedly, when the masses unite, establish a party to represent the interests of the common man, and get it elected to government, it's generally called 'Socialism'. That this is considered a dirty word in America is still more evidence that the Americans support the imperialists.

Re:Russia

[Anonymous Coward]

You must think of North Korea as a fine example gobal capitalism. The hunger, it's made of people! People!

Re:Russia

[caluml]

My god, if you press me I can come up with at least 100 (no exaggeration) acts of congress that are appalling, and offensive to the average American.

Unfortunately, I think the word average doesn't mean what you think it means. Or rather, it means what you think it means, but it isn't the right word to use there. Perhaps substitute "outward looking, progressive, intelligent" and you'll be more accurate.

Re:Russia

[sdpuppy]

Are you really afraid of the Cuban army? Really?

Dang, man, ever see those cigars they smoke?

Anybody putting one of those things in their mouth, you run from if you know what's good for you!

Re:Russia

[minvaren]

My kindgom for mod points.

Re:Russia

[Beyond_GoodandEvil]

Russia did not invade Vietnam. The United States invaded Vietnam because it is an historically paranoid state, and feared that communism would takeover east Asia were the grass roots movements of communists not exterminated
You know who else invaded Vietnam? China.
  How many dictatorships have we sponsored with our money and military technology?And if you don't think that America is an imperial empire... well. We have 700 military bases in almost every country of the world, and outspend the rest of the world in military expenditures. What else could I say.
I don't know if you heard, but after Nov. 4th all Americans were absolved of their white liberal guilt, so stop thinking such late 20th century thoughts and enjoy the new age of Aquarius.

Re:Russia

[Shakrai]

Who really wanted the Patriot Act?

Well, most of our elected officials in Congress and the half of the country that voted for GWB in 2004, apparently. But you can keep on believing it was the "military-industrial complex" if that helps you to sleep at night.

Senators and Congressmen create and pass laws and funding measures all the time that only benefit the corporations.

Which by extension would benefit the shareholders of those corporations (do you have a 401(k)?) and the employees thereof. Mind you, I'm not a big fan of corporate welfare but it's not nearly as one-sided as you are making it out to be.

Citizen participation in politics only occurs when they are under the illusion (delusion really) that they have any meaningful effect on the outcome

Yeah, because voting never has a meaningful effect on the outcome. It's not as though there have ever been close elections before.

Re:Russia

[Shakrai]

If you have $100m to spare, form a political party, and then vote for it. The ruling elite are only a ruling elite because people keep voting for them.

Who is this "ruling elite" supposed to be anyway? It's not a racial class in this country. It's not a financial class -- having money certainly helps you get into politics (just as it helps you get into a good school or land a good job) but it's not a prerequisite. You can find your share of non-rich people within the halls of Congress. You can find even more of them if you look at your State Legislature and local government. So who exactly is the "ruling elite"? I'm dying to know.

Admittedly, when the masses unite, establish a party to represent the interests of the common man, and get it elected to government, it's generally called 'Socialism'. That this is considered a dirty word in America is still more evidence that the Americans support the imperialists.

Socialism is a dirty word in this country because socialism tends to stifle individual liberty and the ability to innovate. It might be a workable model for other countries and I don't begrudge them for adopting it -- but it's not something that I would want to see implemented here. I've had enough of the nanny state as it is without giving it more power.

Re:Russia

[memco]

"If there is hope, it lies in the proles..."

Re:Russia

[aztektum]

Just because we're "represented" by idiots who we elected in a democratic fashion doesn't mean his statement was false.

Re:Russia

[Vancorps]

As a side note here, socialism isn't a dirty word for every American and a great many people do vote for third parties.

You simply cannot paint the American people with one brush, the strength of the country has always been through participation of people with opposing ideals. It forces everyone to compromise and make decisions for the greater good.

Quite naturally this system isn't perfect and the last 8 years are pretty solid evidence that we still have a lot more work to do. Still, America's population is the most diverse of any other nation with some shifts happening in other countries as they realize that if a German scientist has the solution to your problem, you hire the scientist rather than focusing your efforts on reconstructing his work on your own.

I won't say there aren't imperialists in government and that a lot of people even support them but there are also lots of socialists which is evidenced through our social security and medicare systems which are in the process of getting expanded.

It's a giant pendulum which swings from back and forth letting us try new strategies which doesn't always work out for the best but we have to keep trying, adjusting as we go.

Re:Russia

[geekoid]

"Russia did not invade Vietnam. "

Who said they did?

Vietnamese Communist fought against the south Vietnamese government.
Both sides supported by the big powers wit the same ideology.
Of course it was the red scare of the '50s that was the reason Military advisers were sent there to support the 'containment' policy of the era.

"The press release doesn't characterize...

[hendrix2k]

...the laser used in this experiment, but it may have been this one."

that's not true, theoretically

[someone1234]

You might find some antimatter deposit, somewhere.

Re:that's not true, theoretically

[Corporate Troll]

Where? In some natural magnetic field? Even, then... how are you going to extract it?

Re:that's not true, theoretically

[LucidBeast]

With a magnet or electric field?

Re:that's not true, theoretically

[apostrophesemicolon]

with a continuum transfunctioner, silly!

Re:that's not true, theoretically

[Ihmhi]

Just take it from the antimatter containment pods, duh.

Re:that's not true, theoretically

[Corporate Troll]

That's my best guess too. However, would the generated "extractor" magnetic field not merge with the "container" magnetic field? I foresee a lot of problems, but there are smarter people than me who'll probably know the solution ;-)

Re:that's not true, theoretically

[HertzaHaeon]

With antimatter shovels, duh!

Re:that's not true, theoretically

[entgod]

how are you going to extract it?

Maybe you don't, all you have to do is fling blobs of matter into it and collect the radiating energy

Re:that's not true, theoretically

[VoidCrow]

I think you'd have to take a *long* road trip to find it.

Re:that's not true, theoretically

[Anonymous Coward]

In antimatter Soviet Russia, . . . never mind

Re:that's not true, theoretically

[Anonymous Coward]

*thinks about it* Nah, can't you just make a black hole engine?

Re:Lasers^wGold

[Rtech]

Is there anything it can't do?

It's supposed to be Dilithiam Cystals not GOLD!

[itsybitsy]

Now we have to rewrite all those star trek episodes... or do we... Gold Pressed Latinum anyone...

However, you could create the antimatter slowly

[Colin Smith]

And annihilate it quickly.

 

Not enough anti-sunlight

[Anonymous Coward]

> Does anyone know if this might someday lead to antimatter plants?

Nah, there isn't enough anti-sunlight for them to grow....

6 billion euro wasted?

[xonen]

Does this mean that CERN just spent 6 billion euro for building a useless device called LHC?

a bigger bomb

[SethJohnson]

In this same vein, I came across another massively explosive device-- a tanker ship carrying liquid natural gas. Check out this quote:

"If it was an LNG tanker seized, we're looking at something potentially catastrophic," said Candyce Kelshall, a specialist in maritime energy security at Blue Water Defence, a Trinidad-based company that provides training to governments and companies combating piracy. "An LNG tanker going up is like 50 Hiroshimas."

Seth

Wrong laser!

[PhilHibbs]

Not this one?

So easy

[CSLarsen]

> Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear. It sounds sooo easy. Why didn't anyone think of this before?

"Great Heavens! That's a laser!"

[Antique Geekmeister]

"Yes, Dr. Scott. A laser capable of emitting a beam of pure anti-matter." It looks like we can no longer shout back 'Then it's not a laser!' Yes, some of us are old enough to remember going to the Rocky Horror Picture Show before it was a cult classic.

Re:"Great Heavens! That's a laser!"

[yours truly zerocool]

The LASER is misnamed; the expanded abbreviation is Light Amplification by Stimulated Emission of Radiation.

However the internal mechanism is not an amplifier, but an oscillation chamber. The proper name therefore is Light Oscillation by Stimulated Emission of Radiation, or LOSER.

Re:"Great Heavens! That's a laser!"

[notnAP]

Now the only choice is between being shot and being sent back to Transexual Transylvania (in the state of New Jersey).
Talk about being stuck between a rock and a hard place. (pun intended).

I'll tell you what's the matter ...

[clyde_cadiddlehopper]

We in the movement for the right to self-annihilate prefer to call it pro-nothing, not anti-matter.

It's <= 1kJ in any case

[omuls are tasty]

This is the most powerful laser at the facility, firing 2x1kJ per hour.

In any case, I think that Goldmember would disapprove of such practices with gold

Great! combine all the recent news...

[master_p]

1. laser weapons.
2. proton beams (CERN).
3. flying cars.
4. cloaking devices.
5. antimatter production.

Now all we need is artificial gravity and the road to conquering the stars will open!!!

4 words:

[Anonymous Coward]

Fallout 1/2/3 - Plasma Rifle

simple question

[yours truly zerocool]

for anyone that could and would answer: How could the antimatter be stored or handled for use? Given that these are positrons, would it be possible to contain them is a ceramic container, amongst Hydrogen-1, or both? I found the upthread PET scan remark interesting, but that works by measuring the decaying atoms as they travel through the blood. I don't see a way of using the positrons from the laser in a PET scan. Something like a CAT scan (x-rays) I would understand As an off-sub-thread follow-up, most hospitals using short half-life material are connected to a cyclotron lab via a pneumatic transport tube (the same kind they have at my local Costco)

Re:simple question

[Lord Bitman]

afaik, it has always been too hard to generate antimatter for this to be more than a theoretical question.

Bombs

[Ummite]

This antimatter creation could lead to a bomb device capable of very big destruction, without radioactive creation. This would make possible attack on countries that US would not have attack considering the country spoilage due to radiations. Yes they didn't create a lot of antimatter, but you can do that all day long until you have a mass enough to create the bomb. For conceiling, magnetic field should be enough. And there is possibility of using this into munitions, like a little magnetic sphere holding the antimatter, when crushed into something simply explode.

Magnetic containment won't work

[Kupfernigk]

You may not have noticed that same-charge particles repel. Otherwise you could create magnetic containment boxes full of ordinary electrons or nuclei. A simple experiment with a school Van Der Graaf generator will quickly show you just how strong that repulsion gets when even a tiny quantity of electrons are persuaded to gather in one place. To get a significant quantity of positrons or anti-protons, you are ideally going to need a large, geologically stable area, some very big metalwork and a huge budget. None of the current examples are terribly portable, in fact one of them extends under two different countries.

Of course, if you made do with neutral antimatter you could clump it together, but then your magnetic containment won't work.

Anonymous

[Anonymous Coward]

actually it was this one

https://lasers.llnl.gov/newsroom/in_the_news/index.php#quest

Does it make the shark swim faster?

[Burneypmcgillroy]

Lasers create the antimatter which offsets the matter add in some goose bumps and we have a real friggin' fast weapon here!

Obligatory Buckaroo Banzai quote

[Anonymous Coward]

PROF. HIKITA:
                We at the Banzai Institute have at last found that way. We have created a device called an "oscillation overthruster"... which systematically reorders matter by annihilating electrons, positrons...

PENNY PRIDDY:
        Oh, oh, I get it! What you're saying is that oppositely charged particles collide and blow each other up in a burst of energy. Like a tiny Big Bang, like a... a... a... b-b-Baby Bang!

PENNY PRIDDY:
        Well, I'm, uh, probably just, uh, stating the very obvious.
        (angrily, to herself)
        Shut UP... shut UP...

Shark Lasers

[Jason Levine]

Great. First we had to worry about sharks with lasers attached to their heads. Now we need to worry about sharks with lasers spitting out antimatter beams. Add a Reverse Scuba Suit into the mix and mass panic will ensue!

The Gods Themselves

[Derblet]

Reminds me of a story I read a long time ago.

Clarification: Anti-particles not Anti-Atoms

[Brit_in_the_USA]

They have generated anti-electrons (positrons) http://en.wikipedia.org/wiki/Positron and they are typically considered to be an anti-particle. This happens all the time in the upper atmosphere from cosmic ray collisions with atoms.

Most sci fi geeks yearn for anti-atoms ("true" anti-matter) as a high energy fuel storage or catalyst of yet made technology. Anti-atoms of hydrogen (anti-electron and anti-protons captured in stable anti-atomic formation) were made a few years ago in very small Qty. (approx. 10-100) at Cern I believe. That was much more exciting as with stable containment (I don't know if they managed that) discrepancies in theories of Quantum mechanics and gravity could be tested on these anti-atom counterparts.

matter- antimatter

[p51d007]

But Captain......I can't change the laws of physics! Just keep the matter & antimatter separate or you'll have a BIG problem. You'll have to dump the warp core!

That is not fair

[Technopaladin]

There would probably be a lab tech yelling at you to get out of the way.

antimatter as a terrorism weapon

[davidwr]

Someday, maybe 10, 50, or 100 years from now, we'll have a way to make and store antimatter relatively cheaply.

Imagine if you could hook a device up to 110V electrical mains and produce smallish quantities of antimatter. Now imagine an apartment full of these drawing the typical 70-150 amps an apartment can draw.

Now imagine leaving that device hooked up for a year or two or ten, slowly creating and storing enough antimatter to make a big boom.

Now imagine when there's enough antimatter to take out the building or the city block or more. One of the devices triggers and the resulting explosion triggers the rest.

Let's hope the feds and other agencies are doing tabletop exercises with these and similar scenarios.

Kent? This is Jesus.

[fialar]

Can that anti-matter pop a whole house of popcorn?
I bet it can't!

"All right Jesus, let me have it!"

Electron bomb?

[Taibhsear]

It's been a long time since physics class but if I recall correctly positrons are anti-electrons. Doesn't antimatter only annihilate matter of it's respective type? (ie electron-positron, proton-antiproton, etc.) So wouldn't this antimatter only annihilate electrons? It would essentially be ionizing matter (making it positive) that it comes into contact with, right? And how does a thimbleful of antimatter do anything more than annihilating a thimbleful of matter? (again these are positrons not antiprotons so I don't see how you can make an antimatter H bomb or nuclear bomb when the fuel for those are hydrogen, uranium, or plutonium.)

Forget sodium,

[GargamelSpaceman]

Throw a lump of antimatter into a lake and answer the most important question related to antimatter:

Does it sink or does it float?

Seriously, although most physicists would say that antimatter is attracted to matter via gravity, nobody has ever been able to do the experiment to find out if antimatter falls up or down.

There is at least a small chance that a lump of antimatter would rocket upward, annihilating against the atmosphere as it went. If the atmosphere annihilating against the lump broke it up into little bits, it would create a cone shaped explosion over your head. One would expect the little bits to break up faster, as they have more surface area per volume. As the force of the 'explosion' disintegrated the antimatter lump, the tiny particles would annihilate more rapidly. Unless of course, the explosion drove away any atmosphere from the immediate vicinity. Maybe that force would be enough to make a shield around the antimatter lump allowing it to survive until it got to outer space relatively unscathed. Who the hell knows?

But if it were attracted to matter via gravity, then it would sizzle, but also likely break up very soon. The little pieces would have more surface area than the big lump, and so would annihilate, ( and break up ) faster. The force of neighboring annihilations may contribute to speeding the breakup of the bits. It might be that the end result is a sort of conflagration that increases rapidly in rate.

Again, who knows?

Here's a fact calculated using Frink

15 gallons gasoline / ( c^2 ) -> micrograms

gives 23.365651177125987076 . So 23 grams of antimatter could fill up your SUV. Pretty cool eh? That's 455 kilos of TNT equivalent, or 928 McDonalds Big Macs.

A 60 megaton blast from an H-Bomb is equivalent to 111 billion McDonalds big Macs or 2.79 kg of antimatter annihilated.

Caveat read-or: I am not a physicist. When you annihilate antimatter to make energy, you do so with the equivalent amount of matter. So to annihilate 1 kg of antimatter, you need 1 kg of matter. So possibly, the amounts of antimatter above should be halved, since really, to annihilate 2 kgs of mass you need 1 kg of matter and 1 kg of antimatter. But, whatever, you get the idea.

Re:Forget sodium typo

[GargamelSpaceman]

Should be 23 MICROgrams of antimatter would fill up your SUV.

Obligitory

[tuxgeek]

Warp Drives?

Scotty you're a miracle worker!

[powerlord]

Okay... so they've got one of the Anti-Matter injectors working. ... How long till they get the warp drive back on-line?

Ionize electrons... wha ?

[cyberchondriac]

Anyone else catch this from TFA?

"In the experiment, the laser ionizes and accelerates electrons, which are driven right through the gold target."

Excuse me, but how the hell do you "ionize" an electron?!?
I'm sure they meant to say, "..the gold atoms, and accelerates electrons.."

Antimatter Plasma Torch

[Doc Ruby]

That setup seems an excellent prototype for a nanoscale torch directing antimatter particles at targets aimed by lasers and by magnetic plasma traps. Positrons touching electrons would annihilate, converting some mass to energy in a precise location, that would burn apart the matter connected at that location.

How do you manage the FTL travel?

[Anonymous Coward]

> For other values of distance:
> 4.3 ly nearest star 3.6 years

Is there time dilation in there, or are you traveling faster than light with that acceleration? Because I have a hard time seeing how you can travel 4.3 ly in less than 4.3 years without going faster than light.

Re:How do you manage the FTL travel?

[JohnFluxx]

Right, time dilation and length contraction.

Collide this stuff

[Anonymous Coward]

How about we stick some anti-matter in the LHC and fire it up?

Warp-Speed scotty!

Anti-matter battery

[Roger W Moore]

As long as the energy required to create the positrons is less than MC^2 (and I would imagine it would be)

You imagine wrong. The only way to produce positrons is to convert energy into mass. This requires at least 'mc^2' worth of energy to start with. In fact, because in the vast majority of cases you have to produce an electron along with the positron, you actually need 2mc^2 and when you recombine them you get 2mc^2 worth of energy back. So, assuming you could store it safely anti-matter, it is really just like a battery.

To make use of anti-matter as a power source we would need to find a way to convert matter into anti-matter. Energetically this is allowed but various conservation laws get in the way. However, since we know that the symmetry between matter and anti-matter is a broken one (we live in a Universe dominated by matter if you need proof) it might be achievable in the future depending on exactly what causes the symmetry to be broken. With our current understanding, while not technically forbidden by any fundamental conservation law, we know of no process which could, say, convert a neutron to an anti-neutron.

Alien Spacecraft Use Element 115 instead of Gold

[Junior Samples]

According to Robert Lazar, former Area 51 physicist, element 115 is used as fuel generating antimatter in an Annihilation Reactor which powers the craft. http://www.boblazar.com/closed/index.html

Details of Annihilation Reactor operation are here: http://www.boblazar.com/closed/reactor.htm

strawman

[Anonymous Coward]

I see what you did there. You push a position onto your opponent that suits your argument, rather than having a real discussion. Clever tactic indeed.

Re:strawman

[Alex Belits]

How else am I supposed to respond when I face a blatant appeal to authority?

At the doctor...

[badkarmadayaccount]

Five...

What, years, months, days?

Four...

Three...