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CERN Antimatter Experiment Produces First Beam of Antihydrogen
An anonymous reader writes "Matter and antimatter annihilate immediately when they meet, so aside from creating antihydrogen, one of the key challenges for physicists is to keep antiatoms away from ordinary matter. To do so, experiments take advantage of antihydrogen's magnetic properties (which are similar to hydrogen's) and use very strong non-uniform magnetic fields to trap antiatoms long enough to study them. However, the strong magnetic field gradients degrade the spectroscopic properties of the (anti)atoms. To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field (scientific paper)."
I hope not. A future controlled by CERN is terrifying.
Anti-hydrogen weapon?
That is only one ionization away from something potentially very dangerous.
much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
This is eerily similar to the famous Death Star scene in Episode IV. You can even imagine the control panel and sounds are not too different.
"No matter where you go, there you are." -- Buckaroo Banzai
The party potential of anti-H2O is just too great.
I want anti-helium so I can inhale and talk LOWER.
something less useful? what could be more less useful than firing all of our guns at once & exploding into space?
This may be a case where the experts are too close to the problem to see the simple solution.
Put the antihydrogen in a container made of antimatter, then annihilation will not be an issue.
Perhaps some sort of rigid anti-dirigible
Stuff that anti-matters.
The first step towards the inevitable anti-Hydrogen Economy, yay!
http://arxiv.org/abs/1106.0847
One of the most interesting physics papers I've read in recent years. Does away with dark matter by presuming that antimatter has the opposite gravitational sign as matter (which pops out very naturally once you apply CPT to general relativity).
As the electromagnetic force is almost 10^40 times stronger than gravity, it would be virtually impossible to test with anti-protons or positrons. But with electrically neutral anti-hydrogen, it becomes potentially testable.
You may like cowering behind your monitor, sitting in your own filth of chip crumbs, and typing with your sticky fingers; but you're the argument against anonymity on the internet.
"To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field (scientific paper)."
Let me guess. It involves the use of Dilithium crystals.
Problem?
100% of the mass turns into energy, so anti hydrogen + hydrogen = 2mc^2 joules, IIRC.
Oh, and IIRC, two photons are produced as the carriers of the energy, in opposite directions to conserve momentum.
Doesn't the anti-hydrogen have negative mass, so the combined mass of the hydrogen and anti-hydrogen would be 0? I understand that two photons are created, but I'm not quite sure where the energy comes from.
Is 1563649 a prime number?
Erasing moderation
emt 377 emt 4
1) is true
2) is true
3) is true... but incomplete, and slightly misunderstands the nature of electromagnetism
electromagnetism is a force carried by photons between protons and electrons -- or between antiprotons and anti-electrons (which are also called positrons). since a photon is its own anti-particle, it's the same force. so we can use *electric* currents to generate magnetic fields that control positronic currents or the movement of charged antimatter.
one way to view a positron is as an electron moving backwards in time. (literally. when feynman was doing his phd with wheeler they used this extensively.) given that, it's obvious that positrons have to be influenced by electromagnetism. it's just an electron in reverse going back around the spiral.
Antiparticles have the same mass as their particle counterparts. We haven't actually found anything with negative mass yet, and only have the hypothetical tachyon in that category.
Yeah, he rails against Internet anonymity and uses a pseudonym to post. He should make his post under his real name otherwise he's being a hypocrite.
Oh, I guess I need to do some more reading. I had the impression that anti-particles were basically the opposite of regular particles in every way.
Is 1563649 a prime number?
Nope. Quantum numbers are the opposite, but that's a more subtle thing, since there are particles -- including force carriers -- which are their own anti-particle (which immediately implies, for instance, that positrons and electrons are both influenced by magnetic fields in exactly the same way, just with opposite charge). Mass isn't a quantum number, but is rather... well, basically, a form of energy, so particles and their anti-particles have the same.
(To entertain myself adding a layer of complication on top, super-symmetric partners of particles *do* have different mass and aren't anti-matter. Assuming they exist, which personally I suspect they don't.)
Can I use it in my Anti-Zeppelin?
That would be a Led Zeppelin (kinda like a lead balloon...you can look it up).
They turn into "energy", but it may not be very straightforward. Electrons and anti-electrons (positrons) usually annihilate to a pair of gamma rays - about as close to "pure" energy as you can get.
Anti protons and protons annihilate in a more ugly fashion since each is a bag of quarks. You can get pions that decay into neutrinos and muons which then decay into positrons and neutrinos. The muon decay is fairly slow - ~2 microseconds, enough for them to travel almost a kilometer.
In the end you get gamma rays, neutrinos (of various types), electrons and positrons. The combined energy (both their mass energy and their kinetic energy) of all the particles adds up to the original mass energy of the matter and antimatter, and any other energy put into the process.
Because protons and anti-protons are complex, it is very difficult to make anti-protons - only something like 1/100,000 collisions generates one, the rest just make pions and other junk. Then once you have the anti-protons its difficult to slow them down enough and cool them to where they will combine with the positrons. Is a very impressive and complicated experiment.
BTW- it is not a path to any reasonable energy storage, the efficiency of making anti-protons is much too low. I don't know of any even design concepts that would have usable efficiency.
Antiparticles have the same mass as their particle counterparts. We haven't actually found anything with negative mass yet, and only have the hypothetical tachyon in that category.
Tachyons don't have negative mass, they have imaginary mass (i.e. m^2 is negative).
I think this is a good sign to go ahead and start building the Enterprise. Too early?
"Antiwater would explode if it came in contact with standard matter.
I do not immediately see trolls."
Then lets find some trolls and test that antiwater idea out.
You can be against anonymous and in favor of pseudoanonymous without being a hypocrite.
There is a huge difference between anonymous and pseudoanonymous.
Pseudoanonymous allows users to be blocked, get a reputation either good or bad, and actually
have a presence. It's been shown that people are even more true to their real self
when using a pseudonym. That's completely different than the anonymous people that
post stuff just to get a respond and would immediately be banned and/or ignored if they had
a real account.
Yeah, he rails against Internet anonymity and uses a pseudonym to post. He should make his post under his real name otherwise he's being a hypocrite.
Shouldn't you be chasing down a refurbed WWII battleship?
Jesus was all right but his disciples were thick and ordinary. -John Lennon
I thought a Led Zeppelin was more like a New Yardbird...
Jesus was all right but his disciples were thick and ordinary. -John Lennon
Can you put it into a biker gang analogy for me, Dr. Flytrap?
Jesus was all right but his disciples were thick and ordinary. -John Lennon
Sure. When a bunch of Mongols fight a bunch of Hell's Angles, no body mass is lost, some of the mass ends up as blood splatters, some as body parts. If motorcycles are used in the fight, the the total mass energy of the bike-bits will be the same as the starting mass energy.
OK?
I'm a proton, and it blew my electrons clean off, you insensitive clod! I had to move in with relatives to remain stable.
Table-ized A.I.
Anti-Zeppelin sings "Stairway to Hell"
Table-ized A.I.
From:
http://physics.aps.org/article...
Published March 25, 2013 | Physics 6, 36 (2013) | DOI: 10.1103/Physics.6.36
One symmetry that has so far avoided any signs of breaking is the so-called CPT symmetry, which equates matter and antimatter at a fundamental level.
With this data analysis technique, they determined the antiproton’s magnetic moment to be pN=2.792845(12), which has equal magnitude, within experimental uncertainty, to the NIST CODATA recommended value for the proton magnetic moment of pN=2.792847356(23). Thus the magnitude of the antiproton and proton magnetic moments differ by less than 5 parts per million, in agreement with the CPT theorem.
If CPT violation did occur it would forever alter our understanding of the universe—or lack thereof! History has taught us that experiments such as this one play an important role in shoring up, or changing, the foundations of physics. So for now, the debate will go on.
- Zav - Imagine a Beowulf cluster of insensitive clods...