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The Reactionless Space Drive?
waimate writes: "This New Scientist article describes some physics that is claimed could be the basis of a new space drive, and a reactionless one at that.
Our current knowledge of physics requires that a space craft throw most of itself away at high speed in the opposite direction to get anywhere, and this is why the Millennium Falcon won't exist any time soon.
A drive that doesn't depend on reaction mass would change all that. But is this it? The article seems to sidestep the obvious flaw." Or flaws, maybe.
This, along with those oxygen-free speaker cables and a good tube amiplifier, would be the makings of a top-notch stereo, I think.
The problem would be the liquid He delivery truck that would have to come by every week; that could get expensive!
Just imagine how much better they'd sound!
I always wondered why you could not build a spaceship as a large electromagnet and push against the background magnetic field of the solar system. Navigation enabled by changing the orientation of the generated magnetic field. I am not a scientist, so, this is just the idle speculations of an old science fiction freak. Why wouldn't this work?
I saw no mention of a reactionless force at work. The article simply states that when the magnet is turned on, it will move if there is a metal object in the magnetic field. I'm no expert, but I seem to recall from high school physics that a magnetic flux in a conductor will create a current in the conductor. That current will in turn create a magnetic field. I'm sure this is just some quirk in induction theory where small lightweight magnets have a force exerted on them by a magnetic flux. I'll have to hit the books when I get home tonight, but I'm sure this is NOT alien hyperdrive technology.
Remember, You are unique...just like everyone else.
I'm really astonished at New Scientist giving this one house room.
From the article, it appears simply to be a high-tech version of the trick where you can propel yourself forward in a boat, or on some kind of wheeled cart, by moving slowly in one direction and then quickly in the other. The slow movement is not sufficient to overcome static friction, and nothing moves, while the rapid "jolt" does overcome friction and the boat or cart moves.
In other words, the whole effect depends on friction, and would not work in space. This is one of the oldest and commonest kinds of erroneous or fake perpetual motion or reactionless propulsion systems.
Steve Linton
Assymetric magnetic field. It sounds kind of kooky... they're making it for a brief period of time, but if such a thing were to be created for an extended period of time, a force could be generated just by being in the presence of any magnetic field, or any object which responds to magnetic fields.
They'll probably find out that either it is a wobble and not a shudder, or it will turn out to be in a random direction.. just like all the other quantum weirdness... Sort of like propelling yourself off Browninan motion... only magnetically. It looks neat under a microscope, but it would never work.
But I'm just guessing based on a reporter's interpretation of a brief interview with a scientist.
Friction! The same way you can propel your self across the room while sitting on a wheeled chair.
If you take advantage of friction, then you can actually get somewhere without touching anything other than the chair.
If you jolt quickly and then return to your original position slowly you've got a chance of getting somewhere, but good luck doing this in space.
Steve
[ approaching AI ]
My little brother's version invoice cyclotrons and relativistic mass changes, very original. Robert Goddard was very young when he invented his version. If anyone is interested I have a fortran program that simulates this, it ran ok on an IBM 1130/ IBM 360 OS/ Fortran 66 system I'll send you for a nominal copying fee - hey it takes time to photcopy all of the punch cards
Apocalypse Cancelled, Sorry, No Ticket Refunds
I can think of one way they could use this technology, but the idea has already been conceived. They could use the SC magnets to power a rail similar to the ones used by bullet trains to launch a load on a given trajectory. it would be interesting to know whether by 'reactionless' movement, if they have found that the chamber in which the sc is contained felt to exerted force? that being the case, a rail could be built in orbit around earth to launch loads to distant destinations... could facilitate deep space exploration, but only so far as we could calculate a safe return trip via gravity - much like the first trips to the moon.
Yes, I see how you could get around the conservation of momentum. But the physics is entirely theoretical...
First, get the magnet's start-up judder to be at a relatavistic (> ~.5 c) speed. Then, by reducing the current slowly (non-instantanious), make the return-to-center movement at sub-relatavistic speeds. Since relativity says that as you accelerate you get heavier, the momentum of the judder will be greater than the momentum of the return movement. In fact, the closer to lightspeed the judder is, the faster your acceleration will be (the greater the difference in momentum.)
Oh, and for reference, if you'd like to play with the math/physics of this, the relatavistic ratio is sqrt( 1 - (v*v / c*c)): where v is your speed and c is the speed of light. This ratio affects mass, time dilation, and length (along axis of movement).
Let me conclude with: IANAPhysicist! However, this does seem to be the logic that these physicists are following.
Do you like Japanese imports?
That's about the best concept I could get out of the article as well. Of course, this poses two problems:
Okay, here's a design for a system that would be entirely contained, and yet still allow you to generate inertia:
You have two counter-rotating flywheels bouncing along their axis of rotation forward and back in the ship. As they reach each end, they are accelerated in the opposite direction. As the flywheels are moving forward, increase their rate of spin, as they are moving backward, decrease their rate of spin. Since mass increases with velocity, the flywheels will have a higher mass as they are being accelerated backward than they will have as they are being accelerated forward. So you will accelerate forward.
Admittedly, it's not quite feasible, but it does show that a reactionless drive doesn't violate any physics. Yes, it does violate Newtonian physics, but that's because Newtonian physics is only an approximation to reality (and so might relativity, but a more accurate one).
If we actually understood what gravity is, we might be able to get some interesting reactionless (did Clarke just make that term up?) propulsion methods out of it. I'm thinking along the lines of making space curve like it would if there were a mass there, but whereever you want it to. Assuming thermodynamics, this would take a lot of energy, but it might be more efficient then just dumping burnt propellant out the back. Of course, this is probably impossible.
BTW, can anyone point me to a real discussion of how to build a fusion ramjet? It's a staple of a lot of sci-fi, but I'm curious how you keep from getting slowed down by collecting the hydrogen.
400000 cycles/sec * 1-2 cm/cycle * 1m/100cm
=4000-8000 m/s
or 14400-28800 Km/h
Still not quite warp speed, but 10x faster does make a difference =)
The problem with this thing, as everyone has pointed out, it that it doesn't have anything to push against. But space isn't empty. It's full of all kinds of stuff floating around, stuff that can easily be ionized. A magnet switching at the right frequency could pull the ionized material toward it, and then repell it. A spacecraft could suck ionized material in the front end, accelerate it down the middle and then expell it out the rear.
/.
I've thought about this for a while, even named it the 'Squid' drive in my own head. Move the magnetic fields to the outside, and they would provide protection from other hostile things in space. Unfortunately, I'm not rocket scientist or physicist, have no ties to NASA, and have not idea how to even begin to explore the idea any further.
So I just lamely post to
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Here's an example:
After I testified before the House Subcommittee on Space on my participation in the passage of a couple of laws to reform NASA's rather nasty attitude toward private launch services I was pretty close to being out of money. Civic responsibility will do that to you if you don't watch it. Even so, a company whose rocket technology I liked was on the ropes -- a couple of weeks from closing their doors. The CEO gave me an impressive sounding position with the company, offered me a percentage in the company and I maxed out my credit flying around to see what I could do to help salvage the business with no guarantee of compensation.
The first day I arrived at HQ, a strange call came in to the CEO. Some guy claimed to have been referred by NASA because he wanted to find out how to obtain certain kinds of permits that the company had obtained. It turns out the guy wanted a permit to let a device he had made go into space. He said he had constructed a high power vibration stimulator as a diagnostic aid in his business, which was vibration isolation in some mechanical systems, and the damn thing malfunctioned. The problem is this particular Damn Thing, when it malfunctioned, started vibrating off to the side of the table and then it fell off -- but before it hit the floor, it turned in mid air and went up at an angle, hitting the ceiling of his shop where it hit so hard it left a dent in the metal conduit -- and it didn't just bounce off and fall to the floor, it stuck there until he unpluged the infernal contraption.
OK, well the obvious questions were asked like: "Was the conduit a feromagnetic material?" etc. "Are you sure it actually accellerated up to the ceiling or did it just jump up and somehow stick there?" -- you know, the standard Skeptics Society stuff.
This character got my curiousity, not having ever run across one of these conservation-law-violating-sonofaguns before, so I took one of his phone calls and started asking him innocent questions -- like, "How many tests have you run on the device since that time? Have you taken any quantitative measurements? What are the numbers? What did you to do get these numbers?" etc. The interesting thing was he gave me two sets of numbers from two tests, with different weights attached, he said he conducted on a playground with a fishing line attached to the thing to pull the plug on a cellular phone battery at a given height. The numbers he gave were distance traveled vertically vs time. In one test the calculus told me his upward force was less than in the other run by a big margin. So I asked him if he had changed anything else between the two runs other than adding the weight to one of them. He said no. So I asked him to describe his test procedure very carefully. He went through the process verbally, and at one point he said he "turned the variable resistor down until the thing started to lift off -- then I backed off". "Was the resistor in the same position both times?", I asked. "I don't think so because the heavier test run required more power."
Oh, gee whiz -- here is a guy who is not only imagining he ran a levitating device straight up in the air from a playground, but he fabricated results that were inexplicable except from an error in his experimental procedure that he himself seemed not to have thought about. He also told me that on the third run he had some friends of his with him to help and the thing lifted off but then exploded leaving a "line of metallic powder across the playground asphalt". This is either one hell of a smart sociopath playing mind games or he is a covert operative or he is some sort of genius at dreaming things up on the spot that even his conscious mind couldn't have fabricated or he is, in some important sense, telling the truth.
I admit it -- he had me hooked. I invited him to dinner and even though he was a couple hundred miles away, he drove his company truck up to meet me. I won't say what the company name was, because that would give a bit too much information away but it was a company name that was like a double-entendre or pun on his activities that reflected both his mundane business and this weird business of levitating infernal devices -- just the sort of the thing that your dream state would make up and Jung would analyze for you or maybe something that Jaques Vallee would report in one of his weirder "encounter" reports or maybe something that some covert operative would do to mess your mind up or maybe something a complete psycho would do because the little man in his head told him to. So anyway, I had dinner with him and he seemed genuinely worried when I told him that if this was real, he should take precautions by placing a disclosure with an trusted accounting firm to be put in the public domain upon his death or disablement. I don't think he thought I was going to kill him but he could pick up from me that I thought he should be more cautious.
So now what? OK, so he says he is going to build another version of it, because he thinks he knows the principle of operation, but he wants it to be lower power and lower frequency so it doesn't explode and hurt someone. He tells me how his experiments are going but he never seems able to get the original, unequivocal, levitating performance -- all his reports are closer to the rest of the legendary reactionless drives that always end up with marginal effects.
Finally, I tell him to send me a video tape of the thing either accellerating upwards or in a pendulum test and if he doesn't I won't be interested in talking to him any more, but if it shows an unequivocal force, I'll fly him to SV to talk to guys with some capital. He sends me a video tape. It is a short tape with some sort of noise on it. A friend of mine said it had been degaussed but with some sort of external magnetic field -- not by a tape recorder. So I call the inventor and tell him it really isn't OK to send me an erased tape. He seems at first incomprehending and then a bit afraid but then composes himself and starts speculating on how it might have been degaussed in transit. So he says he'll send me two tapes, one via UPS and one FedEx. I never received any packages, his phone is disconnected and I never hear from him again.
To wrap up the story, sort of, he did tell me the electric motor make he used, so I went to an electric motor place -- an old one that had been around since the early 60s. I asked for the specific motor and the proprieter turned around to the assistant and said "Do you remember that guy from the Apollo program at NASA Ames back in the 60s who was building the flying saucer? Where did we order that motor from?"
OK, that's enough weirdness for now...
Seastead this.
Anyone remember this article? It sounds like Science Fiction but as the poster mentioned, it would be cool. Even if it doesn't work, it sure makes for a great background story for a SciFi story. (Why do the Tie Fighters have those big sails/wings? Maybe they are angled against the Universal background quantum flux to provide inexpensive acceleration.)
Waltz, nymph, for quick jigs vex Bud.
So what's wrong with "Cello!"? Voila is French. Viola is a strange wooden thing you wedge between your neck and shoulder and scrape with bits of dead cat. Tim
I take it this is some kind of lightweight, high-output motor. Do you have info on the type/model?
Newton was partially wrong. There are some loopholes.
A hundred pounds of lead or a hundred pounds of ping pong balls?
If you voted for Nader, THIS IS ALL YOUR FAULT!!
I still don't understand how we can get around this, and the article doesn't seem to sidestep this issue so much as ignore it (or I'm just wrong :). Anybody care to shed some light?
Anyone see anything in this article that resembles scientific methods? I don't see that this guy tried to prove that no reactionary force was applied to the coil by the magnet. The coil could simply be massive enough compared to the magnet that no reaction could be observed. The lack of detail is disturbing.
Gamingmuseum.com: Give your 3D accelerator a rest.
A physics teacher will tell you that the mass of an object increases with its speed. An object accelerated to near light speed becomes more massive and more inert, i.e. harder to push. My idea was to make a module that alternates between being heavy and light by accelerating and decelerating internal masses. You could then push yourself away from the module when it's heavy and reel it in when it's light.
(An example of such a module would be a disc that spins fast or slow.)
I was pretty sure right away that there had to be a catch. I thought perhaps my physics teacher was just being imprecise when he said mass increases with speed and that the module couldn't change its mass as it appears to the object doing the pushing and pulling. Could it? I still haven't gotten a straight answer to that question.
I did however hear another idea why this wouldn't work. Even if you can alter the mass of the internal masses (the spinning wheel), that wouldn't necessarily equate to altering the mass of the whole module. You would need a lot of energy to spin that disc up, and you'd take a lot of it back when slowing it down. Whether the energy is in the disc or your energy storage device wouldn't matter. It would equate to mass either way (picture the energy storage device as an identical disc and this becomes clear). As far as I can see, you could get around that with a remote energy source.
--
Fuck the system? Nah, you might catch something.
Well I guess this way you still loose reaction mass, just not in the form of matter; that is you can accelerate the matter lost to light speed.
It's not even original:
That is how the concept of the antimatter drive works;
A giant mirror behind which meeting of matter and antimatter emits a ray of light which pushes the spaceship forward.
I'm still trying to figure out what people mean by 'social skills' here.
You're probably right (from what I know as a 2nd year theoretical physics student), but just thought that I needed to point this out:
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(from my fortune cookie file, most of you have probably seen this one several times already =)
http://mp3.com/jje - Ambient music etc.
http://mp3.com/jje
"Baka." --Ruri, Mobile Battleship Nadesico
Yeah, but how do you propel yourself across a room on a wheeled chair -- without touching the ground / walls / etc? Friction.
Not that it would work in the cold hard vacuum space without some serious crack-pot factor...
Steve
[ approaching AI ]
It's only logical that scientists try to bend (or even break) the laws of physics, since they can't make a 400-ton spaceship that can channel the power of a supernova out of their tailpipes.
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
...so it must be the day to copy an article out of The New Scientist.
...that this will work out to anything useful alone, let alone boost spaceships. It *still* pushes material the other way, namely the metal in the magnetic field. The only thing it could be useful is when the bit of metal is on earth and the magnets 'jolt' themselves into space. But currently the jolt is only about a centimeter, and adding more magnets means you get more weight. A spaceship would need so indcredibly much more power that I can't believe someone even thought of calling NASA about this...
I believe posters are recognized by their sig. So I made one.
Are they ignoring the Newton laws?
the outer limit of grant aquisition attempts.
Given enough hydrogen, just about anything is possible.
"'The crucial thing', says Millis, 'is whether Goodwin's magnet would produce any net motion at all--it might just sit there and vibrate.' "
Consider this thought experiment: e=mc^2. Now imagine a substance that can withstand increadible heat w/o undergoing a phase change. When it is very hot, it's mass is greater than when it is cold. Now:
The thing is, the spacecraft gains more forward momentum in step 2 than it looses in step 4.
That wound, of course be very inefficient due to all of that heat radiating away, but it simplifies the explaination. In practice, the mass would be inside a cylinder made of the same substance and would transfer it's heat (by radiation) to the cylinder wall. A heat pump (almost entirely UNLIKE the one that heats a house no doubt) would transfer it back in step 1.
Now, consider the magnet again. Imagine if it accelerates away from the matal block very quickly (for a very short time), and returns to rest position slowly. It has more mass when it is moving away than when it slowly returns. In this case, it would produce no net acceleration for the spacecraft (since it would still have it's large mass when it decelerated), but the spacecraft would 'judder' forward slightly further than it would move back when the coil returned to rest position.
In both cases, I keep wanting to find that missing bit of reverse momentum that leaves the spacecraft vibrating uselessly in place, but I just don't see it!
This is not true. There have been several solar sail prototypes flown that demonstrated this exact concept. A gyroscopically stabilized spacecraft can use an angled solar sail to change orbits around the earth just as well as it could in solar orbit.
Your implication is that solar sails are little more than dandelion seeds blowing on the solar wind. They're much more useful (and navigable) than that.
Shut up and eat your vegetables!!!
Some people have already vaugely mentioned there might be a way to get gravity to accomplish a similar thing... and there is, the slingshot. At first, I was very uncomfortable with it, since it seemed like the ship gains energy and momentum (since it's velocity increases) "magically". However, what it in fact does is absorb momentum/energy from the body it slingshots around. Of course, a spaceship has far less mass than a planet, so the orbit isn't really effected.
To me, I don't really see any innovation at all here - if I understand correctly, he's saying you could use a magnetic field - and a screwy one - to push the ship away or attract it. But why bother when gravity is already there? After all, that method of accelration has already worked quite well for all those satelites we send to the outer solar system. Plus, iirc, force decreases with the square of distance, so he'd have to have one hell of a magnet for it to work anyway.
Please read the article and create a meaningful title to the post.
I don't like
I remember from my days at Berkeley in physics when a bunch of crazy idiots used to flood the news groups with crap like this. It made getting real info from the newsgroups difficult and it was hard for non-physicists to distinguish the crap. I always remember NewScientist as being the lead name of the 'cult'. Now I'm sure!
They've now just described an electric motor! Yeah!
Photocopying punch cards is obsolete. These days you should scan them to a CD-RW.
The reason for the rocket moving forward is simply the conservation of momentum. The exhaust gases move in one direction and since they carry momentum, the rocket must compensate for this by moving in an opposite direction carrying an equal amount of momentum.
The rocket does not "push" against its exhaust gases in space or against the air or ground on the Earth. In fact, rockets work best in space where there is no air resistance!
There was a guy who tested a "flying saucer" at NASA Ames in the '60s (I was in the Navy there at the time). However, this flying saucer, while novel, was not magic. It was disk shaped and had 6 or 8 Wankel engine driven ducted fans pointing downward. There was even an attempt to take it commercial (I *think* it was call a DiscoJet - and this was pre-disco days :-)
So maybe this little bit of wierdness is explained by the mundane.
The only good weather is bad weather.
It would be funny if they get it to like mach 4 and the casing breaks and the little pelet thing flies around the room and through a few scientists , imagine re-telling that story to everyone who asks how " bob " died, " the strangest story he was implaed by a test capsule for a experimental space propulsion system " sounds like a urban myth , the kind you fortnightly get e-mails about . Laugh with me , bwwaahahaha ( tone : evil laugh number 12 ).
Well, I would agree that the article was painfully short on details. But I don't neccessarily think it was crap. Here's how I think they think it would work (reading between the lines).
1. The earth has a big magnetic field.
2. We can easily create big electromagnets with symmetrical magnetic fields.
3. Since the magnetic fields are symmetric, we can't use them for propulsion, or we would all be flying around in magnetically propelled cars already.
4. This potential new discovery of an asymmetric magnetic field gets around the problem of #3 by letting us build an asymmetrical magnetic field that will push against the earth's magnetic field, thereby producing propulsion.
5. They have to switch it on and off super fast to keep the field asymmetric.
Personally, I suspect that when the magnetic field collapses it will push in the opposite direction, thereby negating the effect. But maybe if you spin the magnet so it points the opposite direction when you turn it off...
I hope that somebody with a really strong understanding (like, a PHd grad student) of electromagnetic fields posts a big explanation in here somewhere.
Torrey Hoffman (Azog)
Torrey Hoffman (Azog)
"HTML needs a rant tag" - Alan Cox
well not if you think of it in a group of them ... one on its own will just jump back and forth, but add a large number of them and they can push off each other and yes i know its silly but think of something on a table vibrating it moves because each time it vibrates it jumps a little,and then it jumps back but why does'nt it just wobble back and forth? because it pushes agaist the table,yes but the reason it only pushes agaist the table in one direction is evrey time it jumps foreward and lands, it does'nt vrbrate the other way as fast(with less moment.) in space you have nothing to push of, but it would still have an effect (more so if you had say ten groups of ten fireing one at a time inorder) ...... off i go to draw a diagram ...
While quantum physics give us signifigantly better results for smaller (sub-atomic) physical systems, it hasn't been proven correct by any stretch of the imagination, and there are still an unknown number of forces we have yet to isolate, let alone understand
Quantum mechanics is a theory. You cannot prove a theory correct. You can only prove it wrong by supplying a counter-example. Quantum Mechanics has been confirmed time and time again in many, many experiments and I think that QM is now a generally accepted theory. There are quantum theories for each of the fundamental forces, which are only three (gravity, strong, electroweak) i.e. all interactions of matter are explained by those forces. Let's just say it would be extremely surprising if there were other forces. Another point, IIRC, Quantum Chromodynamics (the strong force theory) has a problem at high energies, but is still accepted as good prediction model for low energies.
Solar sales are ugly: Imagine the Enterprise with them....
- if you love something, set it free; if it doesn't come back, hunt it down and kill it
Your Jedi mind tricks will not work on a Troll.
8==========D
This is completely bullshit.
When you turn on a magnet, electrically conducting objects will have to encompass the magnetic field. This induces a current. If the electrically conducting object is superconducting the electricity that will flow will completely cancel the magnetic field, and the electric current will continue to repell the magnetic field until something external happens. You can balance a superconducting piece of material above a magnet using this effect.
If you have a non-superconducting piece of iron, and you turn a strong magnet on, the object will jolt. This is a force between the magnet and the iron. So the magnet will be repelled by the iron and vice versa. Nothing mysterious. Nothing that will drive a spaceship.
Some guy saying that "there is unresolved physics" does not make me dismiss a century of well-verified physics.
Roger.
Yours isn't even a palindrome...
--
Igor Presnyakov stole my hat
Many years ago I figured out a much better magnetic reaction drive that will work and is pratical. I'll first explain it using a mechanical analogue and then describe a electromagnetic implementation of the idea.
:)
The mechanical analogue :
Imagine a metal ball on a rod attached to a second rod via a rotary joint. Spanned over the rod-to-rod joint is a linear actuator.
Ball
Rod 1
Rod 2
Rod 2 is achored to the space ships hull.
Now imagine the actuator is unpowered and you swing the ball around. This results in a strong centrifugal force outwards. The rods are pulled into a collinear arrangement.
Now as the ball is swung around, the actuator actuates to decrease the angle between the rods from 180 degrees to , say, 90 degrees. In the quadrant of the rotation in which this happens the centrifugal force is reduced as the distance from the ball to the anchor point is reduced. Note that the angular speed of rotation stays constant.
This results in an occilatory centifugal force acting on the hull. The weakening and strenthening of the centrifugal force will occur at specific angular swing positions. Now to remove the lateral ocilatory effect on the hull you need a second ball and rod arrangements rotating as a mirror image to the first one :
Ball Ball
Rod 1 Rod 1
Rod 2 Rod 2
Note that altough I cant draw this, both balls are achored to the same point on the hull and they rorate in opposite directions.
If this is done properly you have a osilating backwards and forwards thrust (no lateral thrust) on the hull BUT the foward comnponent is greater so there is a NET forward thrust.
Lastly you add another pair of balls and rotate them in such a way with the first two to cancel out the reverse thrust so that a NET CONSTANT FORWARD thrust is produced.
i.e. Energy in (nuclear power pack ?) = Work done in accelerating space ship.
Note no fuel is consumed ! Direct conversion of energy into work done in accelerating spaceship.
The acceleation will be low (cant take off in Earth's atmosphere !) but in space the constant accleration can eventually result in enormous speeds.
This is a clunky mechanical way of doing it, which works ( I've built a prototype !).
A more elegant implemetation is to cause four magetic metal balls to follow the same paths described above using external magnetic fields.
Again no fuel consumption : Energy diretcly transformed into work done accelerating craft.
A good energy source would be a compact nuclear reactor (i.e. submarine type) this could power a large manned exploration type mission. Or alternately you could use a nuclear isotope power source to propel a satelite sized device.
Pretty sweet eh ? No, "It's very speculative. We don't know if it'll work," from the article, this does work
I open source this concept to be used by all at will.
No, that technology only works in an atmosphere. It works by superheating the air directly behind the cone to push the cone forward. This is done with a ground-biased laser. What the other posters were talking about was firing a laser from the ship similar to a rocket engine - except it uses light for reaction mass.
I have great faith in fools - self confidence my friends call it. - Edgar Allan Poe
True but...
Gravity drops off by a square root the farther away you get from center of mass. Therefore, the 200 or so miles you gain can be used for your advantage. And there is nothing that limits you from using a 'space elevator' as a giant magnetically fired gun a few hundred miles long.
You're right about Sol's gravity well though. A space elevator doesn't do much for that.
Actually, this is great science.
They observed a phenomenon, developed a hypothesis, and now will test the hypothesis. That's how it's supposed to work. They even seem pretty skeptical about their own theory. It might be totally bogus, but they're doing it right.
An awful lot of the stuff that gets recognized as good science is crap. Usually in the form of develop a hypothesis, run experiments to confirm the hypothesis, explain away conflicting results.
You never really know how close to the edge you can go until you fall off.
Many years ago I figured out a much better magnetic reaction drive that will work and is pratical. I'll first explain it using a mechanical analogue and then describe a electromagnetic implementation of the idea.
:)
The mechanical analogue :
Imagine a metal ball on a rod attached to a second rod via a rotary joint. Spanned over the rod-to-rod joint is a linear actuator.
Ball
Rod 1
Rod 2
Rod 2 is achored to the space ships hull.
Now imagine the actuator is unpowered and you swing the ball around. This results in a strong centrifugal force outwards. The rods are pulled into a collinear arrangement.
Now as the ball is swung around, the actuator actuates to decrease the angle between the rods from 180 degrees to , say, 90 degrees. In the quadrant of the rotation in which this happens the centrifugal force is reduced as the distance from the ball to the anchor point is reduced. Note that the angular speed of rotation stays constant.
This results in an occilatory centifugal force acting on the hull. The weakening and strenthening of the centrifugal force will occur at specific angular swing positions. Now to remove the lateral ocilatory effect on the hull you need a second ball and rod arrangements rotating as a mirror image to the first one :
Ball _________ Ball
Rod 1 _ Rod 1
Rod 2 _______ Rod 2
(Note : lines just there to force correct word spacing.)
Note that altough I cant draw this, both balls are achored to the same point on the hull and they rorate in opposite directions.
If this is done properly you have a osilating backwards and forwards thrust (no lateral thrust) on the hull BUT the foward comnponent is greater so there is a NET forward thrust.
Lastly you add another pair of balls and rotate them in such a way with the first two to cancel out the reverse thrust so that a NET CONSTANT FORWARD thrust is produced.
i.e. Energy in (nuclear power pack ?) = Work done in accelerating space ship.
Note no fuel is consumed ! Direct conversion of energy into work done in accelerating spaceship.
The acceleation will be low (cant take off in Earth's atmosphere !) but in space the constant accleration can eventually result in enormous speeds.
This is a clunky mechanical way of doing it, which works ( I've built a prototype !).
A more elegant implemetation is to cause four magetic metal balls to follow the same paths described above using external magnetic fields.
Again no fuel consumption : Energy diretcly transformed into work done accelerating craft.
A good energy source would be a compact nuclear reactor (i.e. submarine type) this could power a large manned exploration type mission. Or alternately you could use a nuclear isotope power source to propel a satelite sized device.
Pretty sweet eh ? No, "It's very speculative. We don't know if it'll work," from the article, this does work
I open source this concept to be used by all at will.
In practice, it's difficult but not inconceivable. The effect gets stronger with the cube of the vibration rate. You need a very fast vibration, and experimentally it's really hard to accurately measure force on something vibrating that fast. So experiments so far have been somewhat inconclusive. The interesting thing is that there's no new physics postulated here--it's all a natural consequence of general relativity.
This is clearly fuzzy math.
8==========D
11*43+456^2
Return of the Dean Drive/Davis Drive!
Search on Google for "Davis Stine reactionless" and you'll find an entry into all of this wonderful world.
Summary: Davis and Stine maintain that there's a 3rd derivative force. Normally this balances out; but in transient circumstances, you can get it to show itself. Their best demo was a mechanical gadget that had an unexplained 3 degree phase angle.
Essentially, it's changing the system "before" the reaction force gets there. I don't know about this; if you think about physically long objects, Relativity would seem to prevent a reaction in less than twice the end-to-end light time - so there might be something.
Henry Troup
His background is rather questionable, and so is his story.
"Hot lesbian witches! It's fucking genius!"
As a practicing particle theorist, let me tell you what you got right and what you got wrong (more right than wrong!):
You cannot prove that a scientific theory is the correct description of the universe as we observe it...you CAN disprove a theory by showing that it conflicts with experiments. You CAN prove that a scientific theory is logically correct, but that doesn't prove that it is physically correct.
Quantum mechanics HAS been confirmed time and time again, but we ALREADY KNOW that QM is incomplete, just like we know that Newtonian Mechanics is incorrect (the point particles of quantum mechanics have been replaced by the quantized fields of Quantum Field Theory). QM is, however, "accurate enough" for almost all purposes where Newtonian Mechanics fails, and in the correct domain of application (anywhere where the corrections from QFT are small), QM is still used. I would go so far as to say that there are no practicing physicists who don't believe in the validity of QM; it would take some truly astonishing discovery to unseat quantum theory (it may happen, but I wouldn't hold my breath, just like I wouldn't hold my breath for any evidence that Newtonian mechanics ever fails on macroscopic scales).
There are four generally accepted forces (gravity, strong, weak, and electromagnetic), and there is a QFT model that "unites" the weak and electromagnetic force (and is called the electroweak force), although it isn't technically proper to call it a "single" force, but that is a nitpicking detail (having to do with the fact that the gauge theory describing electroweak interactions is not based on a "simple Lie group", but that is neither here nor there for purposes of this discussion...).
There is currently NO accepted quantum theory of gravity, although string theory provides a mathematically consistent physical theory which includes gravity. String theory (probably) has no currently testable consequences (we need a lot more work before we'll be able to ask questions that experiments have a real hope of answering).
While it WOULD be extremely surprising to discover a fifth force that operates over macroscopic distances, most (particle) physicists fully expect that there are additional microscopic forces that will be discovered in the next decade (supersymmetry is the sexiest these days, but there are many others: topcolor, technicolor, etc.)
QCD is well accepted as the proper description of the strong force, and is well tested at HIGH energies (not low). At LOW energies, it is a very hard theory to perform calculations in, and we have to resort to lattice monte carlo methods, which are computationally speaking, among the most demanding computer applications yet devised (for those with undergraduate physics backgrounds: you can't do a pertubation expansion in the low energy theory, as the coupling constant is a number of order 1, not a small expansion constant, and technically, we can't calculate what the fundamental degrees of freedom are in the low energy limit.)
>..application of elementary grade school physics.. ---
Which fucking elementary grade school did you go to?
I wanna send my kids there when/if I ever have any.
Without the pad, it's not Dance Dance Revolution, it's Listen
Where are you reading where the guy who proposed this idea is absolutely confident it will work? I read it more as if he was saying "hey, this is kind of cool. I'd like to see if it actually works out..."
Eviscerati.Org: All Hail the Eviscerati
Lazar did not state that the propulsion systems were magnetic, but stated they were electrogravitic. By this, he meant that an electrical attraction was used to pull the ship through space. An electrogravitic drive would work by having two conductive materials, the leading one larger than the other, seperated by a non-conductive material. Supposedly, the attraction would pull the drive through space. The idea was pioneered by Th. Townsend Brown and was shown to work on a minor scale. It is said that if you were to build one and measure the weight of it, you would see a decrease in weight. This is exactly what classical physics says can not be, but Brown demonstrated that it might work. No public testing has occurred since, though it is rumoured that the stealth bomber of the US Air Force has an electrogravitic system built into its wing,
Pax Digitalia
No, it moves 1-2cm from zero velocity. For the second "jolt", it will already have a velocity, and will accellerate more. Also, your calculation assumes that any practical application propulsion system will have the same scale, which is probably not true.
If I remember correctly, about 10-15 years ago, there was a guy (Newman?) who claimed to have invented an electric motor that generated more energy than it used. I believe he managed to convince some otherwise intelligent people that the machine actually worked. Given that I haven't heard a peep about him since. The gist of the invention was the engine's windings were *VERY* long and by the time the EM wave reached the end of the coil, the rotor had flipped positions. This sounds almost identical.
The ultimate mistake in both cases can be summed up in a single sentence:
The are using quasi-static EM approximations when a fully dynamic model is required.
To explain:
Coming up with complete solutions to Maxwell's equations can be very complex for all but a few, relatively trivial geometries. However, many times, these equations (and their solutions) can be greatly simplified by making a quasi-static assumption. For example, if you can assume that the magnetic field is chaning sufficiently slowly that the dB/dt is negligible, the equations become much simpler to solve. The equations resulting from neglecting this term are referred to as the EQS (Electro-Quasistatic) model. Many basic circuit and, by extention, electric motor, equations are based on this model.
The problem is that in both of these cases, the changing magnetic field cannot be neglected and many (if not all) of the equations and assumptions they are running with aren't valid. Even people who understand the equations sometimes forget the key assumptions that led to them.
For example. Assume you have two identical perfect capacitors with capacitance C. You charge one of them up to voltage V. The other one has no charge. At this point the energy in the system is 1/2 CV^2. Now, connect these two capacitors (assuming there are no resistive losses). Half of the charge ends up in each capacitor. The total energy is
2 * new capacitor energy
2* (1/2 C * (V/2)^2).
1/4 C V^2.
Which is half of the original system energy. If there were no resistive losses, where did the energy go?
This ceases to be a mystery when you consider that acceleration of the charges in the capacitor is no longer negligible. An accelerated charge radiates energy. It is these radiative losses that explain where the missing energy went.
Yes, I know its not a perfect example but it illustrates the kinds of paradoxes you run into when the underlying assumptions of your model break down.
If that's what they taught you about rockets in highschool, then they taught you wrong. What they probably also didn't teach you is that inertia can be altered (in a charged capacitor for example), and that you can use this effect to generate a (small) force, without the reaction force.
imagine how much noise this thing would make... in being the worlds largest vibrator. has anyone been to a club and felt some real good bass? mabye if it was flying saucer shaped, we would have the worlds largest sub-woofer. :-)
i also believe everything i read on the internet, especially if its on slashdot.
-- Betting on the survival of the media industry is a serious risk. I advise investing elsewhere.
You are missing a couple of points. Most importantly, the rocket equation doesn't apply here, at least not the way I read this. It looks like the statement being made is that it is possible to have a engine with NO exhaust mass. In that case, the problem is bounded by Newton's third because NOTHING CHANGES outside the system. There is no net force because we eject no mass. The real question here is, "Is Newton's third really universally correct or have we found a loophole?"
I think that the title "New Scientist" is fraudulent, if the editors will allow this cr*p to be printed.
When I was about 4 years old, I learned that I could sit in my little red wagon and make it go somewhat by rocking fore and aft. But that's not "reactionless drive", instead I was jolting backwards hard enough to break the static friction so the wagon went forward, then leaning forwards more slowly so friction kept the wagon from rolling back. That is, I was using a rather rough and inefficient way to push against the Earth.
If you toss an iron bar from the nose of your spaceship to the rear, the ship will lurch forward a little. When you bring the bar back to the front, the ship will move back. The center of gravity never moved. To actually get somewhere, you need to push on something outside the ship (for instance, by emitting a stream of high-velocity super-heated gas). This is called "Conservation of Momentum", and you should have learned it in high school.
Could you propel a spaceship by pushing against the magnetic field of the Earth, Sun, or galaxy? That doesn't violate the laws of physics, although the fields are so weak, you might take a few centuries just to leave Earth orbit. However, that is NOT what the article is about. Or you can emit EM radiation (light, microwaves, or even low freq radio generated magnetically) in one direction, maybe producing micro-dynes of thrust in the other direction; that isn't what the article claims either.
If NASA is actually taking an interest in this, they've totally misreported the technology, or else the NASA administrator slept through high-school physics and hasn't had time to consult a real scientist or engineer yet. And when he does, there will be rocket scientists rolling around on the floor laughing...
Mark Moss
Unless I have the right to run this program under Windows 2000 (for stability) and to ftp these "punch cards" to my friend in Holland for free, it does not meet RMS's definition of free software.
I propose that you either port your "punch card" software to Visual Basic, GW-Basic, QuickBasic, and perl, and release it under the GPL, or withdraw your offer of "closed-source" software, which is not welcome on this forum.
Thanks, cunt!
Love,
Slashfucker
Gee, looks like somebody doesn't want
The Earth's magnetic field is a relatively weak dipole, so at the equator it decays roughly as 1/r^3 vs the gravitional force field which goes like 1/r^2. However, it is still present. The sun also produces measurable magnetic fields to a great distance (these can be very unstable, but they exist). So even though the magnetic field decays faster than the gravitional field, it is not so much faster.
Anyway my point is that it is not unreasonable to imagine something that can travel around using these fields. Momentum can be transfered via photon exchange (ie through the fields) and thus the object could accelerate. This doesn't seem like it would be very efficient in terms of power consumption, but using super conductors, there is no loss to heating, so the only loss would be to the photons that accelerate the object around.
This means that an object with such a propulsion system might be able to move itself around the solar system without any reaction mass. That means that it could accelerate around indefinately as long as it was receiving solar power. Lots of probes are limited by the amount of reaction mass that they carry. It forces NASA to use very arcane calculations to make the most efficient trips around the solar system (look at the trajectories of the Voyager sattelites for example). The whole point of a mass driver is that it could use the reaction mass efficiently. But this drive idea would obviate the need for this.
For example, whenever you speed up or slow down on the earth, momentum is being transfered. The earth is the thing picking up and losing momentum. It is just that you never notice it because it is so massive.
"Politics is for the moment, an equation lasts eternity" -A. Einstein
No, it should be "there ain't no such thing as a free lunch," commonly abbreviated TANSTAAFL.
New Scientist is 100% pure pseudo science. I wish there was an option to block New Scientist /. posts.
Ah yes, but if we want a good Brownian motion generator, we don't need to look any farther than a really hot cup of tea. ;-)
Strangely enough, less than a week later I find myself suffering another bout of deja vu.
This is almost exactly the same concept that was put forth in another famous usenet post which title was "Intersteller Spacecraft Engine" or something similar.
The idea was that you generate a strong magnetic pulse at one end of a long armature. When the magnetic field (traveling at the speed of light) reaches the other end of the armature it acts upon another magnet, pulling it towards the first.
The propulsion was supposed to be generated during the few nanoseconds when the receiving magnet was influenced by the field but the transmitting magnet was inert. This would be in the tiny moment after the pulse was transmitted. I suppose the length of the pulse in seconds would therefore correspond to the length of the armature in light seconds.
The usenet groups to which this article was frequently posted never fully came to a consensus as to whether this would work. The discussion was generally broken into three camps.
Camp one were people who thought the idea violated newton, and was therefore crap.
Camp two were people who thought that the radiating asymetric magnetic field would act as the propulsive medium, and the idea would therefore work.
Camp three were people who knew for a fact that this is how the Enterprise's impulse engines worked.
It's actually not like a railgun. It's like a coil gun. In a railgun, a static current is used through two rails and the conducting projectile. I a coilgun, there is no electrical contact between the coils and the projectile, but the time derivative of the magnetic field cause eddy current to run in the projectile, which in turn produce a magnetic moment in the projectile.
-- Please put this in your sig if you think
it can't work. that is what the conservation of momentum law says. no matter how complicated the thing is inside. to give this nonsense credibility they quote *someone* at Brookhaven National Lab. as a BNL employee, should i be flattered that our name is good enough for a hoax or ticked?
I think it was a joke retard oh and "your" is posessive, "you're" is short for you are.
Speaking of which, this is obviously a plot by that damned dirty Green Party to colonize Mars, then return to Earth in 300 years and turn it into a filthy communist hell. All hail the Libertarian Party! Also, I'm sure M$ is involved. Those fscking bastards! Yeah, Winblows suxors!! Linux r00lz, d00dz!!
Time to die, nerd-boy!
Unfortunately, the magnetic field of a coil drops rapidly with distance (it drops like the field of a dipole at long distances). That means the chunk of metal has to be close, preferably even sit inside the coil for the thing to work. I would say this is a joke, I really don't understand how this can get into a magazine that claims to have a scientific contents.
-- Please put this in your sig if you think
I agree that the relevant thing here is the law of conservation of momentum. However how can the electromagnetic wave carry away so much momentum.This would be like trying to have a space ship run by emitting a light beam - Surely ejecting mass is more effective.
I dimly recall a sci-fi story about an anti-gravity field that collapsed almost instantly...useless until somebody got the bright idea of generating the field sequentially with a ring of generators so that the field never had time to collapse, thus creating in effect an invisible space ship. Sci-fi speculation seems to have an odd way of predicting technology; if it can be imagined it will be accomplished. Matria
I absolutely agree, there's one more law too:
If noone believes it will work, it'll never be tried and become a self-fulfilling prophecy.
- Steeltoe
http://www.debunkingskeptics.com/
I hate how people confuse UFOs with alien spacecraft. A UFO may be an alien spacecraft, but an alien spacecraft can never be a UFO. If you know it's an alien spacecraft, it's no longer unidentified.
Anyway, the idea behind magnetic propulsion is that the Earth acts like a big magnet and provides the opposite reaction; as you move forward, the Earth moves back by a small amount.
--
Among the tools in my workshop is a cheesy little "vibra-sander" with a 3 inch square plate that twiches at 60Hz when you plug it in. It does seem to sand a bit faster than a wooden block. At least the proposed superconducting magnet design would certainly work for this. No fatuous usenet physics would even be required!
Even your spin-around idea has problems. Even though you can't get work out of a symmetric field, you'll still develop a force from it. If you rotate the magnet around you will likely be getting a force component in the wrong direction for a significant portion of the rotation, potentially negating the (small) gains from the field on turn on/off.
Just for the sake of argument, you could implement the spin-around technique fairly simply by rotating the superconductor at high speeds (with good tolerances) and making your switch time equal to 0.5 the frequency. The problem is that you'll be looking at rotational frequencies of 800,000+, which are rather hard to achieve!
I suspect the answer is simply that the force exerted on the "ship" by the asymmetric magnetic field in fact pushes the field generator (magnet) in the opposite direction.
As the article suggests, if you did this repeatedly and cyclically, the object would simply vibrate.
Energy is always conserved, although it's form may change (kinetic to heat, etc, although that's largely semantics). Momentum must _always_ be conserved.
-Puk
To fuel the "Judder" drive
Macka
"We've got switches now that can work at high voltages at 400,000 times a second," he says. "If you could use one of these switches to rapidly switch the magnet on and off, you might get some propulsion out of it."
Seems to me you would have a 400,000 hrz vibrator... Not much usefull for propulsion.
Some days I get the sinking feeling Orwell was an optimist.
Sort of makes you wonder what kind of drugs "Time Cube" is using ... and in what quantity of truckloads per day.
utter rubbish
Yes, electromagnetic fields can carry momentum. But why go to such elaborate lengths just to generate an EM field? Just shine a laser out the back of the space craft - much simpler.
-josh
(posted with mozilla 0.6)
AFAIR he turned out to be a hoax - he was a brothel owner (with no background in physics) who made a quick buck out of the press.
Of course, that's what the US government wants you to think =P
--
A rail gun typically has two rigid conducting rails surrounded by a large electomagnet. A projectile is placed between the rails. The projectile usually is coated with a thin conducting layer.
The magnetic field is created by applying a large current to the coils. Then, a large current applied to the rails. The resulting "short" circuit vaporizes the conducting layer on the projectile producing a conductive plasma.
The projectile is the propelled down the "barrel" of the rail gun by both the expansion of the plasma but more so by the resulting Loretz forces that are result of the interaction of the electrical discharge and the magnetic field. This force is perpendicular to the magnet field and direction of the current flow and can be quite substantial. It is this force that accellerates the projectile to a very high velocity. Damage to a target is primarily because of the kinetic energy of the projectile strike the target.
The military examined rail guns in the 80's. There was talk of "electric" ships that contained rail guns and lasers at the height of the Reagan "Star Wars" era. The problem with rail guns is they produce a very flat trajectory making them useless for over the horizon applications. Reducing the velocity of the projectile would reduce the kinetic energy of the projectile thus requiring heavier projectiles or explosive projectiles.
Another problem with early generation rail guns involved alignment of the rails. The forces produced in a rail gun often destroyed the rails or knocked them out of alignment. Thus, early generation RGs were limited in their ability to achieve sustained firing rates. I read a few years back that this problem had been corrected. Haven't heard much about rail guns since.
But, the approach of this "juddering" engine and a rail gun at not similar at all. And, until somebody proves otherwise, rail guns are stil confined to the laws of Newtonian physics. Hence, RGs have one hell of a recoil. That is why they were planned for use on ships and tanks as they are the only vehicles massive enough to absorb the recoil. Even the mighty IOWA class battle ships were pushed sideways several feet in the water when she fired her guns broadside.
RD
Hmm, I'd have preferred Warp Drive first, but this does sound rather like "Impulse" Drive... or perhaps just a vain attempt to boost a high caffeine soda :)
Winton
Take a very long ship, point it to the center of the sun. The potential energy difference on the two ends can be used to create energy. The forces on the the ends would be pushing them apart from each other and the STRAIN is the opposite force.
As the ship travels it rips itself apart.
Equal and opposite forces don't have to be limited to length/heighth-width.
Since no one will read this, I'll save it and post it on my website. *wave*
NYC - Perl Programmer - Politics/Government/Economics
We have bigger fish to fry than that. What about all those damned anti-environmental children who build sand castles on the beach? Don't they realize that their castles add friction to the tide and thereby slow down the moon? We can't just sit back and let this irresponsibility go on forever!
---
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
It's not a reactionless drive per se, but solar sails do not have to carry around their reaction mass.
I'm not sure if I'm real.
>2. Surely environmentalists will require us to
>simultaneously send a ship in the opposite
>direction so that we don't disrupt the sun.
Shouldn't then they be worried about all other planets in the solar system which we so extensively use for interplanetary maneuvers? Like Venus, Mars, our Moon, Jupiter, Saturn, etc.? We're pretty much slowing them down with... But maybe this will have to be the next step in environment protection, and we better start now!
--AP
...big ping-pong balls would work best. (and yes I am aware that something along those lines already exists)
A slight digression here, but has anyone ever imagined a network where ping-pong balls were used to comunicate data. If you could get it to run on solar wind (sorta like that fancy blowdryer trick) I bet you could make a near perpetual mechanical space computer. And ping-pong balls would be so easy to ship into space!
Good god, 3h46am and not even bothering to log on as an AC.
I'm a writer, a poet, a genius, I know it. I don't buy software, I grow it.
I am actually amazed the New Scientist published this kind of crap. There is absolutely no evidence that this things is 'reactionless' (even the doofus that made the things admits that). Read the last sentence of the article "It's a definite possibility that any forces arising from Goodwin's concept will only act within the components of the device itself, resulting in no net force," he says. "There are a lot of unresolved physics issues to address." Well duh.
Would people just get over it, repeat after me, 'there is no such thing as a free lunch'.
Now, I am not at all amazed that slashdot picked this up.
-josh
It's embarassing, because the AvroCar in the 1950s used the same idea and actually flew. But it wasn't stable. The AvroCar guys knew they needed automatic stability augmentation, but early 1950s control technology wasn't up to doing that. The stability problem should be solveable today, but the fundamental inefficiency problem of pure-thrust VTOL craft remains.
There was lots of enthusiasm for vertical takeoff craft in the 1950s, and quite a few flyable prototypes, some very wierd, were built. Many of them ended up in the Hiller Aviation Museum.
Other than helicopters, the only VTOLs made in any quantity were the Harrier and the Osprey, both of which are used by the USMC. Both operate as pure-thrust aircraft only for takeoff and landing; they're ordinary winged aircraft in cruise.
It allows you to build the "Giant Slingshot" wonder which in turn allows you to build space marines. The downside is that your opponents can call in massive hordes of Jeans-stealers.
People replying to my sig annoy me. That's why I change it all the time.
shouldn't it be a bit warmer? -269C seems kind of frigid.
"You're turning into a penguin. Stop it."
The spaceship with the new reactionless drive flew into the air exactly the way that potatoes don't.
Remember to read the New Post Office Plan
Any time you put metal in a magnetic field it causes a force on both the magnet and the metal.
This is the principle that is used in a rail gun.
I would think that this would be a little like trying pick yourself up off of the ground by your own hair. The forces involved will cancel themselves out. Maybe their is some physics involved that the article did not describe.
Environmentalists are their own worst enemy. ~tricklenews.com
Time Cube
--
Oh, no! In fact you (Anonymous Coward) are the most active poster on slashdot in all time. You will never fool me there...
1. The article acknowledges that this may go nowhere.
2. This is how most scientific 'advances' are made. Somebody notices something cool about the world around them and builds on it.
3. Seems like a reasonable idea (from a 2nd year physics major) but then again I'm no expert on super-conductors or magnetic fields.
4. Everyone agrees that a new propulsion form(s) is needed for space exploration to become a viable and regular occurrence.
5. This is my first post on slashdot so...just take it for what you will.
The voyagers are now escaping the solar system.
They used chemical propulsion and gravity assisted flight.
Ionic propulsion enables us to go into the stars, we only need some nuclear reactors to feed those thrusters.
Photonic propulsion is more than enought to go into the deep cosmos... the problem being more relativistic than practical.
You cannot proceed from the informal to formal by formal means
Basically, their modus operandi appears to be to search around in the literature for the most outlandish claims they can find, and print them with big splashy headlines along the lines of "Scientists say aliens may have had sex with our women!!!!" (that's an exaggeration, but not by all that much).
So, ok, they only print articles purported to be based on statements or papers from "legitimate" scientists, but as Pons and Fleischman showed us, there are a heck of a lot of reasonably legitimate scientists with wacky ideas out there... way out there :-).
Grain, meet salt. Can I interest you in an edition of the New Scientist?
It's certainly true that it's amazing how many true discoveries in the history of science were ridiculed at their inception. That doesn't mean we should stop ridiculing the truly stupid ideas :-). The truth will eventually take care of itself.
Comment removed based on user account deletion
Here's a wacky thought, but what if someone could find a way to turn the angle of that "equal and opposite" force? What if, instead of being opposite, the "force" was deflected somehow into the superconductors in a circular motion around the hunk of metal that made up the electromagnet? If they are somehow able to make an asymmetric magnetic field then the only other "force" would be the force of shooting the electrons through the coil around the electromagnet, which if using superconductors would be minimal if anything measurable. This may be what they are thinking of. They may be thinking that because they are not creating a "north" and "south" pole in the electromagnet and instead are creating an asymmetric magnetic field they are cutting out the "equal and opposite force." In other words, they may be thinking that the "equal and opposite force" of the north end of the magnet is the south end of the magnet, so if they can create an asymmetric magnet with only a north end they cut out the opposite force and walla, there's your (magnetic) force drive that takes you to the stars. How you can use this single vector magnetic force generator to actually drive your ship to the stars is academic, in their mind, as they have solved the "hard" part.
Or maybe not.
Perhaps they could swim through the vacuum using the 3k cosmic background radiation (swiming through the background radiation the same way a fish swims through water).
Maybe along the lines of an ion drive (where a magnetic coil accelerate seawater through it pushing the craft in the opposite direction of the seawater (for you physics dudes)).
In the distance you hear an ominous moo.
"Ye cannae change the laws of physics". Always struck me as a little ironic coming from Star Trek.
This is just as crazy as those perpetual motion machines, I may be an engineer but I do know my physics well enough to tell you that there will be no net motion and this is just another ploy to gain either notoriety or money. Come on NASA your going to be laughed at if you take this idiot serious...
Nathaniel P. Wilkerson
Domain Names for $13
Nathaniel P. Wilkerson
www.haidacarver.com
Use the the motion properties of liquid helium to push yourself forward. Just have to keep the system Kool.
In the distance you hear an ominous moo.
I hate how people confuse UFOs with alien spacecraft. A UFO may be an alien spacecraft, but an alien spacecraft can never be a UFO. If you know it's an alien spacecraft, it's no longer unidentified.
It's not confusion at all. Saying that if we know that it's an alien spacecraft it's no longer unidentified, is akin to saying that if we know that it's a UFO then it's not Unidentified, because we have identified it as a UFO. It's circular logic at best. I say that unknown spacecraft would fall under the category UFO because, how do we define "which" aliens made it. An airplane of unknown origin on your radar screen would be an "Unidentified airplane" right? You know it's an airplane, but not who's airplane ?, so it's unidentified.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
What's actaully happening here is just Lenz's Law - the conducting object is repelled by a changing magnetic field, and vice versa.
Nothing magical, and this _does_ require reaction mass - the conducting object.
Among other things, this is how coilguns work (not railguns; different animal).
Not sure if it's relevant, but does anyone have links to the (theoretical) behaviours of magnetic monopoles? Are there any quirks of nature we would expect to see if these beasties came up?
Sorry, no links, but you might want to grab a hold of a graduate quantum mechanics, quantum field theory, or electromagnetism text book. Magnetic monopoles come in many shapes and sizes, and are predicted in many extensions to the standard model of particle physics. Perhaps the neatest property is that if there is EVEN ONE magnetic monopole, we have an explanation of why electric charges are quantized (see t'Hooft-Polyakov or Dirac magnetic monopoles).
They would have to be extremely heavy objects, though, or else we would already have seen them and their effects.
Here's one reason this could work. Those who site Newtons 3rd law do so on the assumption that nothing "leaves the engine". It's a closed system. Conventional engines push on their exhaust or leave a trail of energized ions (that have mass), etc.
Well, something does leave this engine. Electromagnetic radiation (you are turning on and off a magnet yes?). Recall duality of matter to mind for a moment and remember that waves are particles as well and have mass. So Newton's 3rd law can be satisfied.
As for Conservation of Energy, you are using energy to run the magnets (and leaking off this radiation) that does not come from nowhere. It comes from batteries and the like which are going to run down because of the EM radiation you project into space. Now you may have solar panels, etc, but we are back in the realm of conventional energy ideas.
So maybe this can work without breaking laws of physics. You just have to think a little bigger. Am I an expert? No. But I've seen thought experiments that suggest you might be able to do this, and they have been reasonably compelling.
For those of you who are trying to remember exactly what law of physics this violates, it's Newton's Third Law of Motion, For every force there is an equal and opposite force. This means if you don't have something to push off from, you can't go anywhere. (Just for those few of us from the slow class: You can push out a stream of high pressure rocket fuel byproducts, which is how these things usually work.)
I don't see how an asymmetric magnetic field and superconductors help you out--where's the opposite and equal force supposed to come from? It's hard to see how the thing COULD do anything but 'sit there and vibrate'.
Seems like extremely wishful thinking to me. If you're a magnetic material and are brought near a magnet, then you will experience a force. But if you're attached to the magnet, you won't go anywhere -- the forces are equal and opposite and balance to zero.
This is the same reason why things like gravity drives don't work. A compact nearby mass will impart a force on your ship, but if you're anchored to the mass (as it's part of your ship), then you'll impart the same force back on the mass and the net force will be zero.
Suggesting otherwise is like expecting that, since you're standing on the surface of the Earth and Earth is pulling on you, the you-Earth system should be accelerating indefinitely way. That ain't gonna happen without something like negative matter.
This sounds like someone saying, "Well, here's a system where there are forces. Maybe conservation of momentum will be violated!" Seems an awfully peculiar conclusion.
max
A spacecraft could suck ionized material in the front end, accelerate it down the middle and then expell it out the rear.
it's called a Bussard Ramjet
Amorphis
Apparently the coupling constant decreases below 1 at high enough energies so that perturbation theory sort of starts to work.
Indeed...the "scale" of QCD (where it becomes strong) is about 1GeV, give or take a few factors of order 1 (right around the mass of the proton and neutron, but I digress...)...perturbative QCD starts to work somewhere above that scale, but really can't be trusted for a while...say 30-40 GeV. By the time you get to LEP energies (200GeV, give or take), the coupling (actually, alpha_strong = g^2/4 PI) is down to about 0.12, and perturbation theory works well.
The professor also said that the coupling constants converge to some common value at about 1e15 GeV.
They do, more or less (but not exactly in the Standard Model). This curious coincidence is one of the best hints for Grand Unification of the three forces.
The fact that they don't meet exactly in the Standard Model is considered (by some!) evidence for Supersymmetry, since in the Minimal Supersymmetric extension of the Standard Model (called the MSSM), the couplings actually DO meet exactly (well, at lest within the current measurement error bars) at somewhere around 10^16 GeV (more or less).
Good luck in the class by the way!
Its been a long time since I sat in a physics class but as far as I can tell, this isn't a reactionless drive. The metal is repulsed by the magnetic field, therefore, if Newton is correct, then the magnetic field is also repulsed by the metal, its just due to the fact that the magnets are anchored to the earth that there is no visible movements.
Or am I missing something?
-----
# cd /
a Higgs field.
Which would be REAL handy if you found a way to push off on that.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
lets bring back cold fusion and the perpetual motion bicyle while we're at it.
A W S ----------- QABO : BALA
This is a common misconception, but gravity goes out to infinity.
Getting out of the atmosphere and into orbit is definatly the hardest part. The problem stems from the need to get out of the atmosphere and up to orbital velocity in short order. Once that is done, fractional G acceleration over a period of years is acceptable if necessary.
That option opens all sorts of possabilities for propulsion such as solar sails, magnetic propulsion (at least within Earth's magnetic field) , ion propulsion (like Deep Space 1), and probably others.
Ion propulsion engines are very efficient because they have a high ve reletive to chemical engines and can gather the energy needed to accelerate from solar panels. Solar panels provide a much greater total energy over their lifetime than the same mass in chemical fuel. Of course, since the acceleration is limited to fractions of G, it is useless until you get into a geo-transfer orbit.
Risk factors play a role as well. Once in orbit, partial failure of propulsion means the mission takes longer. With good contengency planning this is perfectly acceptable for an unmanned mission. In the ground to orbit phase, the same partial failure means loss of the mission and the potential for substantial property damage and loss of life unless the propulsion is substantially overdesigned (which costs a lot of money as well).
The requirement of multiple G acceleration for ground to orbit limits us to chemical and nuclear rockets at the moment. Skyhook still requires getting out of the atmosphere first. The only other idea right now is a mass driver.
So, even though the delta-v is still just delta-v, it IS a lot harder and more expensive to get from ground to orbit than form orbit to anywhere else.
"There are a lot of unresolved physics issues to address." (From last paragraph of article) Well, one of these things that is not unresolved seems to be that the vector sum of the force along the direction of the axis between the magnet and the interfering metal disc would be zero. Another one would be that the amount of energy used to flip the high-voltage switch would almost certainly (unless this switch were itself superconducting) exceed the propulsive force (if any at all) generated by this thing. Yet another might be the amount of liquid helium needed to keep this thing at -300C for a sufficiently long amount of time. Just some thoughts.
"Activate drive....bang...Ow....Drive working...bump...ooh ow....Maximum Bump speed Helm....ow thump bang...."
I want to read about research into really cool drive technology not spaceships (Ion drives, Magnetic Superconductors etc) with the acceleration of an Eastern European car going up a steep hill. I agree we have to start somewhere but more obscure areas of research such as the anti-gravitic properties of superconducting ceramics spinning at high velocity are ignored or worse debunked before they even get off the ground.
"No pseudo literary quotes here"
I thought that was the principle of all guns.
--
"I'm surfin the dead zone
--
"I'm surfin the dead zone
In the twilight, unknown"
> Isn't it all that glitters is not gold?
Jeez... why are we even talking about the mellenium falcon when we haven't even invented chewies yet?? What goods a mellenium falcon without a chewbacca?
How certain is it that there are no opposing forces elsewhere in the system that are currently being overlooked?
My guess is this will go nowhere, but it's interesting nonetheless.
Stupid backgrounds
OK, normally I don't like to post a bunch of links but your post has me wondering. Is this accident just an effect of some type of inertial gyroscopic propulsion? I have heard of such systems (admitedly from the 'alternative' side of fun things related to space) where forced opposition of gyroscopes casues a similar effect. Here are a few links to sites that discuss this phenominon: some patented gyro propulsion ideas
an open source gyroscopic inertial thruster
a list of space drive patents
someone with way too much time on his hands
100 anti grav links Take a look at some of those links (with a grain of salt). I would be willing to bet this guy had some sort of setup that upon 'falling' forced the unit mass against the gyroscopic forces of the motor and thats why his result was it 'flying'. I am not a scientist so excuse my ignorance on the mechanics/physics of this subject. It is fascinating...
Prospecting Stinks. Stop Wasting Time on Cold Calling.
You want reactionless propulsion, I refer you to James Woodward's application of Mach's Principle. A good rundown can be found at http://inetarena.com/~noetic/pls/woodward.html.
In effect, drives at both the front and rear of the cylindrically-shaped craft project gravity wells in front and behind the craft - a positive well in front and a negative one behind. In effect, the craft ends up on a steep slope, constantly falling downhill. To the passengers, the front of the craft is "down", and the rear is up - so one travels to the destination feet-first. To decelerate, the slope is reversed (gradually), and the craft flips around so the passengers don't fall on their heads!
It's been some years since I read the series but it presents an interesting perspective on early 21st century space development, and the 1000 years of human civilization that follows.
I adblock all animated gifs.
Blessed be the prime numbered slashdotters
Newton conceived his third law thinking that space was cartesian. Every acton has an equal and action works fine in cartesian space, in other words, the line that the equal and opposite reation takes is straight, not curved. Einstein's work suggests this line is not straight, but curved, taking this to its logical conclusion would suggest it is not equal and opposte, because it will eventually curve back on itself.
Einstein found one flaw in Newton's equations, that being time is relative to speed therefore not absolute. Who's to say there is not another flaw with Newton's equations.
There is no empirical evidence for dark matter, furthermore anomilies have been observed with the deep space probes, they did not behave as the math said they should have behaved, ergo there is something wrong with the equations.
Nasa is at the present investigating these anomilies.
Newton's work suggests that gravity is only a function of mass, not a function of how things move.
What I would like to know is, what does the mobius strip having one side really mean? Has anybody checked out if it has one side kinetically. Probably not, because everyone knows Newton's third law is gospel.
Peter.
It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
There are some that speculate that space is not a vacume, but instead is filled with gravitons, photons, gluons, etc. These are generally considered to be massless, though they do contain energy. Some speculate that the "dark matter" in the universe is comprised of such energy, and that gravitons, for example, do in fact, contain weight.
String theory, for example, considers that the vibrational patterns of a graviton/photon work in such a way as to cancel out measurable mass. But this is only true in a macro-scopic scale.. At quatum sizes (plank-lengths) you'd see an undulating massive string as heavy as a grain of salt shifting around too quickly to have a high net mass effect.
Gyron theory suggests that space isn't empty at all, and in fact is filled with little spinning "gyrons". Mass is the cohesive and circular movement of these gyrons. Transmitter 'forces' are the wripples in gyrons much like watter wripples which spread out throughout infinity (or until ubstructed where their inertia is finally transmitted). Support for such theory is based around disproving that trasmitter forces have "transverse waves". A key point by such theorists is that the only reason we detect individual photons is because our measuring instruments are flawed and various resonant points are allowing the detectors to measure threshold breaches randomly such that we don't maintain a continuously visible ray of light.
String theory adheres to General Relativity AND quantum physics; touting itself to be the Theory of Everything. Gyron theory (and friends) says that Relativistic warping of space is hog-wash - that mass and time manipulation can be totally explained by aerodynamic "Mach" theory, where you treat the gyrons as air molecules.
Quantum theory itself suggests that in any given micro-scopic region of space, you have particle-antiparticle pairs creating and distroying themselves so long as to be within the margin of error that Heisenburg predicted (making use of discrete plank energy levels). So the smaller you look, the more stuff is there; and the more violent that stuff is.
I'm sure there are other anti-vacume theories. Personally I see growing trends between String and Gryon theory, (especially with String's M-Theory which speaks of multi-dimentional undulating strings which sound remarkably similar to Gyrons).
With that background. I make the point that movement through space is exactly the same as movement on the surface of a planet.. We use Friction. It's a highly efficient form of action-reaction.. Arguably, it takes less fuel to drive around the world then it does to blast off into space (where-after you'd get trips around the world for free). Additionally, the slower we travel, the more efficient it is.. This is because the same forces of friction that we use for travel also impeed us (incidently, this is the argument made by Gyrists as to why we can't breech the speed of light or why time seems to slow down for us). On Earth, solid friction is greater than air-friction, so we're good to go. In space, however, the cosmic-dust (beit undulating transmitter forces, spontaneously generated partical/anti-particle pairs, or locally dispensed plasma) is both our means of propulsion and resistance. Well, this relates almost identicailly with swimming in the ocean.. Namely that you have to move like a fish.
In fact, I think that within 100 years, we'll develop cosmic-dust sensative machines that allow us to build space-ships just like fish. Most likely, these won't be big clumsy metalic flippers extended in our rear, but more likely gigantic electro-magnetic jelly-fish-like nets. And when you're within a solar system, such as ours, you have to resort to various sea-fearing tactics to move around... Perhaps it's as simple as inverting the polarity of a magnetic web, or sending out graviton waves, etc.
The point is that I believe Friction-based engines are far more efficient, and better suited to space travel.. If we compare these two types of propulsion (the other being explusion action-reaction drives such as rockets/jets), we see that on earth, Rockets are arguably faster though they do have a max velocity, no matter how much force is applied. Friction based propellants, however, can theoretically approach the speed of light, so long as you can conceive of the proper mechanisms. Rocket fuel, for example propells atoms at around 20,000mph (from what I remember). You can't propell a ship any faster no matter what volume of rocket fuel you use (though larger volumes accelerate you to that speed faster). Ion-drives, likewise _can_ get you near to the speed of light, but you'll run out of fuel LONG before you ever get there.. Plus you need incredible amounts of propellent volume to achieve enough thrust to be useful; thereby reducing your payload and ultimate speed-limit accordingly.
But with mechanical friction, small amounts of energy (of virtually any form) can accelerate a spinning object (or an object on a rail) to unimaginable velocities.. Our current limitations are frictional heat. Most likely we'd have to discover how to manipulate massless transmitter forces so as to not to have 'unwanted' friction (friction in any direction other than that against the target).
Theoretically, this assymetric magnetic pulse device could be used to send out photon-waves (the transmitter force for electro-magnetism) which amplifies the interaction between charged particles (in our case, it would be the plasma from the sun). Now normally, what you'd do is create a massive electromagnet and hopefully repell/attract yourself from/to the sun. (Note: I'm not informed well enough of plasma to know if it tends to have a net positive or negative charge or both) Howver, frequency carries with it energy. And higher frequency photons should produce a higher impact force on charged particles (which should reciprocate.. which is the theorized method by which two similarly charged particles emit symmetric forces on each other). Additionally, it might be possible to funnel the magnetic waves (e.g. photons), say towards the SUN, or a planet (which has a magnetosphere). This would essentially have the effect of a limited tractor/repulsor beam.
Now, from what I gather about String theory, high temperature and pressure cause the various forces (and associated transmitters) to unify. We currently consider electro-magnetism to be unified, and we've discovered electro-weak properties at sufficiently high temperatures. My guess is that magnetism can distinguish itself at sufficiently low temperatures. Here, I totally speculate, however. Low-temperature super-conductors asymetriclly undulating might have something to do with this dispersal of magnetic and electric charge. We've closed down the science of Eletric waves, but might these magnetic waves have their own uses?
Additionally, since we know how to produce electric-waves, possibly now magnetic waves, it might be possible to produce gravitational waves. One reader suggested the use of high-speed, counter-rotating fly-wheels which would increase relative mass. Though he was shot down because of conservation of momentum, which we might be able to gain from this, however, is that if the reletavistic mass changes are fast enough, we could produce gravity waves. We might be able to achieve greater apparent gravitation to a body such as a planet or star through the use of such undulations.. Undoubtedly energy IS being transfered into the system... Where is it going? Obviously into frictional heat.. And to the general entropy of the system. But we also know that electro-magnetic waves will radiate outwards; why not gravitational waves (through the acceleration). Given that acceleration might contain the link to gravity waves (due to changing of reletivistic mass which acts as a doppler effect on observers due to the probagation delay of the gravity information), a counter-rotating fly-wheel might not be the bets model. I simple piston might be the best example.. Here, we can make use of a mechanical energy (such as a gas-engine or rail-gun), where there is massive acceleration of a mass, only to have the inertial spread out in lateral directions. Compression-based energy transfer is very efficient (at least compared to rocket engines). If massive pistons can be rapidly accelerated and decelerated, back and forth, it's possible that gravitational waves would be transmitted. What would be needed are materials with tensal strength beyond imagine (but we're still working towards that). Additionally, as with the above, it might be possible to make full use of massless transmitter forces some day.
In short, I concur with several other posters that there can be no reaction-less net force. I personally believe that Space is not a vacume (especially not around a star), and that those particles can be treated as air or water molecules for propulsion. Depending on the power-requirements of such devices, it might be possible to use Solar cells for propulsions around a star, which gives you enough momentum to direct you towards another star. If Fusion ever becomes practical, then when a stellar-ship passes around a star, it could collect light and heavy elements for use in matter-energy conversion (which is what happens in both fission and fusion), so as to maintain power until reaching the next solar system. I don't think it will be very possible to change course in-between end-points, unless we discover unimaginable power-storage capabilities (perhaps such matter dessimation.. Since we can't vary well conjure up anti-matter sufficiently to sustain matter/anti-matter condensation)
References:
"The elegant Universe" by Brian Greene
-Michael
The same field that makes spiders and frogs levitate will also be formed into a worm drive. The source of flow will be matter flowing through a core super conducting magnetic tube appearing similar to the engine on the USS Enterprise.
But doesn't coffee have more energy than a Jolt??
Links
gyrons
vacum-less aether
-Michael
Assuming that you have a good mirror on the ship, ground-based lasers could give you up to twice the impulse of a ship-based laser. Plus, you avoid having to carry the engine and fuel along. Of course, you also have to have a braking laser on the other end (or you have a braking engine). This was a plot element in one of Niven's stories (main theme was RNA education pills). The ship in question was a light-sail craft that launched by laser (or by making the star explode), and braked by starlight alone.
Floating face-down in a river of regret...and thoughts of you...
This won't work (unless there is something *very* strange happening - and there is nothing in the story to suggest that).
Basically, they suggest that by rapidly applying and removing a magnetic field on a superconductor, they may be able to violate the law of conservation of momentum. My guess is that this isn't going to happen (for values of 'guess' approaching 'absolutely certain')
Surely the magnet in their lab judders because there are other objects (besides the magnet) in it's magentic field? If it was in space, it would be the only thing in it's magnetic field so what would cause it to move? My guess is nothing. So I don't see that this is going to work. THe only way they can prove it will work is by testing it in a location where it has no surrounding objects. Going by NASA's previous record for spending lots of money on things that don't work properly or aren't thought through, there's a fair chance that they'll test it in space ;-)
Follow me
When I was four. Yes FOUR. I had this theory that if I rolled my bike up the curb, then rolled off it I could gain speed. Then I do it all over agin. Sure it'd look stupid. However I never quite perfected it, the bike always got horribly slow and I'd loose my balance and fall on a mailbox.
:wq! DOH!
:)
Roy Miller
--Roy
So, would the direction of the "shake" change when the device has been pointed at North/South poles? I would imagine that the device would be using the mass of the earth. Based on that, I don't know how well it would work when it's far from any planetary bodies. I don't know why the article was so vague; why can't they test it using one of the 400Khz switches, and see if it works? The good news is that the temperature might not be a problem in space, but the power usage of such a drive might be kind of high.
Actually, it's bits of dead sheep. See britannica.com
Hey kids, there's only 5 days left 'til Yak Shaving Day!
Imagine standing on a kickboard in the middle of a swimming pool trying to propell yourself with the action caused by swinging a bowling ball. I don't see how you'd get anywhere with THIS particular scheme.
Actually, due to friction with the water, you could do it by quickly extending the bowling ball and slowly bringing it back. Of course, that won't work in space.
This "story" should have never been released. Someone somewhere decided it should have. They were both ignorant and wanting a story. Nuf said
All that glisters is not gold.--William Shakespeare: Merchant of Venice, act ii. sc. 7.
HTH. HAND.
What happens if you tell bad news inside a small Italian restaurant? Anybody know about the interaction of bad news and bistromathics? Some nice Italian food might also offset the displeasure which usually accompanies the arrival of a conventional bad news powered ship.
Bugrit! Millenium hand and shrimp!
Ok. I push on the magnet, which pushes back on me with equal and opposite force. I move one way. The magnet moves the other. Oops...magnet is now farther away. If I keep doing this, the force of the magnetic field on the magnet falls off with the square of the distance from it. So, you technically CAN keep accelerating, but eventually the effect will be essentially zero. Oops! Well, what if the magnet is fixed into some frame of reference? If the frame of reference isn't fixed relative to your spacecraft, then what I described will happen. If it is fixed relative to your ship (ie, you bolted it to the rear bumper), then you'll just cause internal stresses within the ship-magnet system. That might generate some heat, but it won't get you anywhere. Sorry...
If it doesn't turn out to be a good space drive, maybe it could be marketed as the
"New, Space-Age Superconducting Vibrator"
[As seen on TV!]
-iceaxe
WALSTIB!
Hey, I came up with an idea very much like this when I was in highschool.
Newton concieved his third law thinking that space was cartesian. Every acton has an equal and action works fine in cartesian space, in other words, the line that the equal and opposite reation takes is straight, not curved. Einstein's work suggests this line is not straight, but curved, taking this to its logical conclusion would suggest it is not equal and opposte, because it will eventually curve back on itself.
Einstein found one flaw in Newton's equations, that being time is relative to speed therefore not absolute. Who's to say there is not another flaw with Newton's equations.
There is no empirical evidence for dark matter, furthermore anomilies have been observed with the deep space probes, they did not behave as the math said they should have behaved, ergo there is something wrong with the equations.
Nasa is at the present investigating these anomilies.
Newton's work suggests that gravity is only a function of mass, not a function of how things move.
What I would like to know is, what does the mobius strip having one side really mean? Has anybody checked out if it has one side kinetically. Probably not, because the scientific establishment knows Newton's third law is gospel.
Peter.
ps. Yes I know I posted this before, but I posted it as a reply to another posting and it looked a bit lost way down in the list of postings, so here it is again just in case it gets missed.
It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
In that case, one would want to make sure that the serving of the Italian food is properly timed to coincide with the arrival of the ship.
One step closer to the infinite improbability drive!
It was asimov. Some short and squat robots that flew to jupiter and outmachoed the not-so-jovial jovians. Turns out the Jovians were gung ho on interplanetary war, but were so scared of the macho humans that they changed their plans, never realising that the robots were'nt human.
IIRC the field flickered like a flourescent light.
I agree with what you say. When I was posting originally I was in a hurry so I worded my post really carelessly so it says that there is a quantum theory for gravity, while there actually isn't. Also, about QCD, I got it backwards, but don't blame me, we just did this in class last week and I haven't studied for it yet :-). Apparently the coupling constant decreases below 1 at high enough energies so that perturbation theory sort of starts to work. The professor also said that the coupling constants converge to some common value at about 1e15 GeV.
The ship was driven out of the solar system by an array of lasers orbiting Mercury, and braked as it approached its destination star by jettisoning(sp?) part of its mirror and using it for reaction mass. It was a decidedly one-way trip, but damn near possible with today's technology.
Bugrit! Millenium hand and shrimp!
I remember in the neighborhood of 15 or so years ago there were some people claiming ot be UFO abductees and Robert Lazarr(SP?) who claimed that the ETs had told them/reverse engineered a UFO and their propulsion system was magnetic in nature.
My first problem with this is if every action has an equal and opposite reaction then how does the movement of the superconducting magnets cause any real change? Sure, their inertia will have an effect, but as soon as they move back into their original position their inertia will cause the opposite reaction.
Imagine standing on a kickboard in the middle of a swimming pool trying to propell yourself with the action caused by swinging a bowling ball. I don't see how you'd get anywhere with THIS particular scheme.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
With finals coming up, and final projects already upon us, I must say that personally, I prefer Red Bull Propulsion, but Jolt works OK, too.
In this metaphor, to cut the string, you'd have to actually have an infinitely long string, which equates to never shutting off the solonoid, which means you get one 'jolts' worth of accelleration, for as long as you keep the charge in the solonoid.
For the picky, rotating the solonoid 180 degrees while charged wouldn't work either, as it would have exactly the same effect on accelleration as shutting it down and charging it up again with a reversed polarity, so charging, turning, discharging, turning, etc wouldn't work at all. It's like a gyroscope in that capacity.
Kevin Fox
Kevin Fox
Surely environmentalists will require us to simultaneously send a ship in the opposite direction so that we don't disrupt the sun.
Laugh if you want. I'm sure that the guy who made the first combustion engine and smelled the exhaust said, "Wow, that stuff is really icky. But I can't see the stuff gunking up the atmosphere, it's not *that* much exhaust."
Climate change from messing up the atmosphere is bad enough - do we really want climate change from moving the sun?
Maybe the state's highest function is to grind out insoluble problems. (Zelazny, Hall of Mirrors)
The idea being that while mass might be more effective, light is easier to carry. Better yet, light is easy to send from the base, so you don't have to carry it at all.
The book Heavy Weather (Bruce Sterling) has a protagonist power a spaceship by rail-lauched iron slugs from the moon. Each one is captured and fired back, speeding the ship up. A bit of double barreling and (see Indistingiushable from Magic by Forward for illustrations) and the coming and going slugs wont collide.
Pretty cool
Skyhook seems like a good idea in theory, but it has one very big problem: The tether, or anything attached to it, cannot be made from an electrically conductive material (Not even a little bit). If it is, you have a conductor moving through Earth's magnetic field. Considering the strength of Earth's magnetic field and the velocity at which the tether will be travelling, the current generated is extremely large. Any resistance at all will cause the tether to heat up and eventually break. NASA did a few tether experiments a few years back. The one I remember had the same thing happen, but the tether was around a half kilometer long. Now, if the tether was made of a superconductor...
Written by a single drunk monkey in 30 minutes with a copy of MS Word 2000.
It was called "Not Impossible!" or something like that. A (millitary?) scientist is trying to determine if those same agressive inhabitants of Jupiter could ever pose a threat to humanity. He happily determines that humanity is safe, because the Jovians require intense atmospheric pressures to survive, and there's no way to maintain such pressures anywhere else. Force-fields? They're useless because they decay so quickly, and it's physically Impossible to make them last for more than a few seconds. Try it and everything blows up.
The story concludes with another scientist specializing in force-fields cruising to Earth in his new invisible force-field ship. After loss of eye and limb to exploding force field generators pushed past the danger point, he figured out that you can cycle the force-fields on and off so rapidly that no atmosphere can escape and achieve the same practical effect. Won't the folks back on Earth be thrilled!
Drifting further off topic, I wish there was some sort of giant short-story keyword index out there. Is there one I don't know about?
So so long as physical things are represented by sufficiently well-behaved objects, and the laws of physics are time-invariant, you will be able to define conserved energy.
This is a deductive conclusion from even better supported observations than conservation of energy itself. In fact, as you said, Newton's conservation law turned out to be false - but since the conditions still hold, you can patch it up with an improvement.
Note: actually, in relativity time-invariance and space-invariance go hand in hand; that's why momentum and energy pair up to form a single "momentenergy" vector.
I've wriiten some of my best code while under the influence of "Jolt Propulsion"
Isn't this the same technology that the super fast trains in europe use?
So we are talking about a speed of 400-800 m/s, faster than my car :)
granted, but I wouldn't expect to get to Alpha Centuri for this side
of Christmas
Steve.
I think as long as there is a marginal amount of movement, regardless of direction, the energy can be harnassed...
Send all information this way please...
"Look at that blubber fly!"
- Homer Simpson, underappreciated propulsion physicist
---
Goodwin says the metal objects create the judder effect by inducing a "brief asymmetry in the magnetic field" as it is set up when the magnet is turned on. This initial disturbance of the magnetic field, he says, creates a repulsive force on the magnet and pushes it away.
So it's not quite the same thing as a railgun (especially because they claim the magnet is repelled from, rather than attracted to, the metal).
Unfortunately, you might still be right that it's like trying to pull yourself up by your hair. As Mills says at the end, "It's a definite possibility that any forces arising from Goodwin's concept will only act within the components of the device itself, resulting in no net force. There are a lot of unresolved physics issues to address."
So, it is possible, but they just don't know yet.
"The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
There's a technological barrier too. A big one. Even when you use computer control on the multiple ducted fans which provide the vectored powered lift to make the thing fly, if the slightest thing goes wrong with the control systems or if just even one of the ducted fans/powerplant loses any thrust, the stability and controllability of the aircraft goes to hell in a handbag instantly. You have to immediately shut down all thrust and deploy your BRS 'chute to survive the forced landing, and hope you have enough altitude for the 'chute to deploy and slow you down before you have a date with a smoking crater. A dead-stick landing in a winged aircraft gives you a much greater opportunity for a survivable forced landing. Hell, even a rotorcraft in auto-rotation gives you some semblance of a chance at surviving a forced landing.
Perhaps the effect you're talking about with the wing could be done with heat instead of pressure. You have one hot side and one cold side. Particles move at different speeds over each and *viola* you have motion.
I need a funny sig
Sorry, I know it sounds like I dismissed the article's claims immediately. I did read the article, I did look at what was observed, and I still can't believe this shit made it any further in the scientific community than some kid who thinks he can fly if he pulls really hard on his shoelaces.
Bugrit! Millenium hand and shrimp!
THere is a way to have a reactionless drive, and yet conserve momentum and energy. You just need to have some 'negative mass'. (Note that negative matter is not antimatter (which has ordinary mass but reversed charge and spin). Negative mass (gravitaionally) repells normal mass but is attracted to it, so if you place a negative mass behind your 'ship' it will chase it and they will both accelerate. If the masses are equal then there is conservation of energy and momentum. As they both get faster the acceleration increases due to relativity (mass increases and distance decreases as you approach c.) Or course there is still the problem of how to stear the thing, or stop it for that matter. And the minor fact that nobody has yet discovered any negative mass. /[][] Ross
If I've got a magnetic field, then presumably something is generating the magnetic field, right? If this is working off Earth's magnetic field, then the "reaction" is that it's giving the planet Earth a tiny push - similarly for any other magnetic field that this operates in.
Am I missing some important point here?
This type of self levitation has already been proven.
The Lorax said nothing. Just gave me a glance...
just gave me a very sad, sad backward glance...
as he lifted himself by the seat of his pants.
And I'll never forget the grim look on his face
when he heisted himself and took leave of this place,
through a hole in the smog, without leaving a trace.
And all that the Lorax left here in this mess
was a small pile of rocks, with the one word...
"UNLESS."
Apparently interstellar magnetic fields are quite significant, here's a reference. There is a more recent article (that I can't find) that suggests that intergalactic magnetic fields may be more powerful than previously believed.
Don't they check articles for any scientific soundness any more, before publishing them? Even a high-school student knows that you need to "push against" something to get a vehicle moving (the road in case of a car, the air in case of a plane, and its own exhaust gases in case of a conventional rocket). This drive will likely work when near other metallic or magnetic bodies, but the effect will dwindle as soon as you get far enough from the earth or any other planet. You could keep it working by tossing out metallic particles out of the ship, but then you'd be back to square 1: need to take a big supply of "reaction mass" with you.
...I enjoyed this ridiculously idiotic thread. Believe it or not, it is people like you that make Slashdot great. Thank you. Take a bow! Hoorah!!
Ouch .. this hurts! I am sorry dudes but I just can't get my head around this. Reason:
/2, then coast at top velocity for a time , then decelerate over a time T /2.
/2. The total trip time is the time spent accelerating/decelerating plus the time spent coasting.
/dt times the square of the exhaust velocity.
I begin with the classical (ie. non-relativistic) rocket equation (I use the classical version because relativistic effects only become important for exhaust velocities greater than about 95% the speed
of light, which is not the case for the powers and speeds we are talking about here).
The rocket equation is:
dv = u ln [ ( M + m ) / M ]
where:
dv = change in ship velocity
u = exhaust velocity
M = ship mass, without including reaction mass
m = reaction mass ejected from ship
Now in general, to get from one place to another a ship must accelerate for some time T
The total change in velocity is v, but since the ship speeds up and slows back down to rest, the maximum velocity is v
Now the power required to eject the reaction mass at the given exhaust velocity is equal to the rate of change of kinetic energy of the reaction mass, which is half the mass-loss rate dm
And that's that!
> My first problem with this is if every action
> has an equal and opposite reaction then how
> does the movement of the superconducting
> magnets cause any real change? Sure, their
> inertia will have an effect, but as soon as
> they move back into their original position
> their inertia will cause the opposite reaction.
A creative possibility:
The magnetic force could have an equal and opposite reaction in an area which is not within range of magnetic interference, due to properties of "brief asymmetry in the magnetic field".
If the opposite force does not originate at the point of contact, then it should be possible to ensure that there are no points of contact from where the opposite force reacts.
However, if the point of contact of the reaction force is at the original point of contact, then the thing aint going nowhere. (?).
I'm no physicist... but it'd be neat if it were possible.
I dont see the resulting devices being too small. The ideal application would be to have such a magnetic drive small enough, and powerfull enough, to launch from earth. If that were possible, it'd be possible to continue in space at high speeds.
I would pity those with metalic fillings... A serious dentist trip would be required. Another problem would be that any loose screws would be near fatal during launch. Any crash would seriously harm the area... what type of power source would be required for a long trip ? Nuclear ? 100 tons of capacitors ? (refuel via solar panels once in orbit?)
-Tim
The article seems to imply that no force is exerted on the metallic object. It would be interesting to let the magnetic object sit free and see what happens to it. If it stays motionless and the magnet goes nuts, cool, but otherwise this may just become another weird property of superconducting magnets.
Need... more... detail...
Not sure if it's relevant, but does anyone have links to the (theoretical) behaviours of magnetic monopoles? Are there any quirks of nature we would expect to see if these beasties came up?
Yes, conservation of momentum is the issue. If it actually violates conservation of momentum, that would be a big deal even if energy were absolutely conserved. But I wouldn't bet on it. It's very easy to come up with things that seem to violate conservation of momentum down here where there are things like friction. Which is why there is the concern that the thing would "just sit there and vibrate" if you were to put it out in free space.
...in my dorm back in school who was in shock after his girlfriend had broken into his room and cleaned it. He was taking it pretty hard: "She cleaned my room..." "I can't believe she did that..." "I can't find anything..."
"Mike," I said. "Remember: for every action, there is an equal and opposite reaction..."
Anyway. The idea of using a railgun as an engine is that you'd use it to fire slugs backward, while the reactive force accelerates you forward. As you said, that's just the standard rocket principle, with the slugs as your reaction mass. You're probably right that it wouldn't be particularly efficient compared to a chemical rocket, but it does have the interesting feature of being a way to turn electricity into propulsion, which might be nice if you have cheap electricity. Possibly solar (like the ion drive, which as I recall does basically the same thing with a particle accelerator) or nuclear (how would this compare to just using the plasma directly?)
It might also let you fine-tune the mass/speed tradeoff more optimally -- with rockets, not only do you have to carry the fuel / reaction mass that you'll be using at each part of the trip for all the preceding distance, but most of the energy that you use goes to accelerate the reaction mass backwards instead of you forwards, right? The same force acting over a larger distance means more work done on the reaction mass. That's why a gun's recoil against your shoulder hurts less than getting shot.
This article seems to be talking about either using a magnet to push against a larger magnetic field, which makes sense, but isn't particularly new, or else some new phenomenon that actually breaks the equal-and-opposite-reaction law, which sounds far-fetched, though I've never claimed to be a physicist (I just play one on Slashdot).
David Gould
David Gould
main(i){putchar(340056100>>(i-1)*5&31|!!(i<6)<< 6)&&main(++i);}
All of you Linux bigots can use the dd command to convert the ebidic to ascii if you have a card reader else just type it in by hand, like I did twentyfive years ago. A GPL release is fine with me. remember this is fortran66, and it will not run under g77 without work. AS IS, NO Warrentees, milage may vary stuff here
Apocalypse Cancelled, Sorry, No Ticket Refunds
Conservation of energy isn't that much of a big deal, it's conservation of momentup that causality kinda hinges on, and I like causality. I think "reactionless" should be read as "not carrying reaction mass", not "there is no reaction to the action". If it's using the sun's magnetic field, then the sun will get pushed back as the ship mnoves forward. Not by much though.
can i mention "dark matter" again? what if there are particles all over th eplace that have enough mass but can't be seen by our current instriments? maybe we can "push" off those to make minor course changes... but i think you will still need traditional thrusters for more controled manuvers or emergency stops
I believe sex is highly over rated... unless it involves me
It is probably too late for anybody to see
this (thus, doomed to no moderation) but
electromagnetics is one of my Ph.D. specialities.
While I don't think his idea will work (well),
many people here are citing conservation of
momentum as the reason why.
However, every post I have seen has not accounted
for field momentum.
For example, it is possible to generate
thrust from an end fire phased array antenna.
Photons carry the momentum away (allowing
Newton's laws to be satified). This is not
practical though because, photons carry very
so little momentum
Even though the photon has a zero rest mass
(if you could bring it to rest), it has a
directed momentum of magnitude:
p_photon = h_planck * f_photon / c
(Consult a quantum textbook for more details.)
If the scientist proposing this idea does it
right, the RF oscillations will constructively
add to spit off photons in a opposite direction
of the device's acceleration.
However, my guess is that to get appreciable
thrust from the field momentum would require
fields and photon fluxes not easily attainable
(I am thinking GW sized power plants for micro
Netwons of force). Thus, I don't expect this
technology to compete with say high specific
impulse plasma thrusters anytime soon.
Kevin
ACTION = - REACTION
(Also known as the law of conservation of momentum.)
So if someone would find a way to violate this law, is would mean that neither classical nor quantum mechanics nor theory of relativity would be valid under these conditions. Would be cool.
But, as I can understand from the article, the researchers seem to focus on the movement of the magnet while they don't take into account the reaction of the "rest of the world". Did they measure the reaction force on the device that produced the magnetic field? Nothing in the article points out that they did.
So at this moment I still keep thinking that they just made a (rather stupid) mistake.
The article failed to answer the most important question: How does this improve MY life?
What the hell good is a reactionless drive to me when my dog is dead, my girlfriend has sex with five different guys a day while making me watch and I can't even solve basic addition problems?
Hundreds of these ideas come to the minds of all scientists everyday and I applaude for them. If they didn't nothing new would ever be invented.
So what, if the idea isn't viable for space exploration. Perhaps someone else can base something more practical solution on it, or not. In any case if it is not viable then no more time will be wasted on trying to create one. This saves time for other projects. Considering that normally every project is at least being done ten times or more all over the world, giving information on a viable or not project is sure to help.
--- Anyway, here's Aniway!
"You haven't heard of the the reactionless space drive? It makes the Kessel run in 12 parsecs."
--
python -c "x='python -c %sx=%s; print x%%(chr(34),repr(x),chr(34))%s'; print x%(chr(34),repr(x),chr(34))"
Just got pointed here this morning, which has a good overview of reaction drive technology now and in the future. Seemed sort of relevant.
http://astp.msfc.nasa.gov/4thgen_main.htmlSee the link 'Really Advanced Propulsion Research' down side bar.
I'm a number, not a free man!
For every action there is an equal and opposite reaction...
Magnet josts one direction, spaceship jolts the other.
Spaceship retracts magnet to repeat process, spaceship is retracted towards magnet EXACTLY as much as initial jolt.
This is a GOOD way to make a vibrator, but a bad way to make a space ship.
Official GOD FAQ.
Model the thing as a sinusoidally-varying magnetic dipole radiating in a beam straight out the back.
With
you findPlugging in B = 5 T, l = 5 m, T = .01 s, I get F = 10000 pounds!
This is a pretty generous approximation, though. The beaming part is one problem (a phased array would be possible, I guess), but the sinusoidal approximation basically means they can start a new jolt on the same time scale as the jolt itself. Unlikely. But, it's an interesting number (if I didn't screw up in the derivation. It is late...)
Physics does indeed say it won't work. The universe, however, has a habit of disregarding how we think it should work.
$ man reality
Obliteracy: Words with explosions
From reading the story, the one reference that could be turned into to a space propulsion drive (in the facts, rather than the lead-in) is the passing reference to a NASA presentation. As for the rest of it, the force is presumably between the magnet and the metal in the field - which is an action on the magnet and a reaction on the metal, presumably - so there's nothing 'reactionless' about it. And they don't mention anything about forces which may arise when the superconductor stops conducting, which is presumably where the 'magnet vibrating' bit comes from.
All that is gold does not glitter,
Not all those who wander are lost;
The old that is strong does not wither,
Deep roots are not reached by the frost;
From the ashes a fire shall be woken,
A light from the shadows shall spring;
Renewed shall be blade that was broken,
The crownless again shall be king.
-JRR Tolkien
Laugh at stupidity: mod idiots +1 Funny.
What, no "Hackers have been using Jolt propulsion in a production environment for YEARS" jokes?
--
Fuck the system? Nah, you might catch something.
Ahh you see ...wait i'm replying to the wrong post ... ok but I'll go on any way. It's not agaist the 3rd law ... because there is an opposite reaction, the recoil of the magnet . . and you are using energy , you have to make a mad big Field for this to work . that takes power... so what happens when the magnets jump and try to move away from the metal but are stoped ?
does the effect just go away ? no it cannt. s oit either causes heat ... except that these are supercooled superconductor. so what happens then?
say you have a large number of these fireing in a well progtramed squence, say the first x magnets fire and jump forward in there cases , then the next x fire, then the next x fire, at this point the first ones have been moved back to the start positions by the movement of the others ...
(think of a vibrator on the floor) except the floor is'nt there so what does it push against ? what about the movement of the other magnets. ..
any way i'm off to look for some info on the topic ..
Claims to 'reactionless' engines are a dime for a dozen. One of the stupidest experiments I've seen involves a 'drive' with a spinning weight, powered by a liquid fuel model aircraft engine. The machine was suspended from one arm of a balance. A counterweight was hung from the other arm.
After a few minutes, the machine ended up higher than the counterweight. The experimentors took this behaviour (it was repeatable, no less! to be evidence of their reactionless drive working. *giggle* No chocolate fish for these guys!
If they claimed it could deflect nuclear missiles, they might get more money to fund more rigorous experiments.
Blancmange
Its pretty clear that the momentum the magnet gains is either countered by the momentum given to the metal, or to momentum put into the electromagnetic field (which is perfectly valid - photons have momentum). There aren't any other possibilities worth wasting time thinking about for now (Occam's Razor is good for this kind of thing).
I wouldn't rely on this as any kind of space drive though - you've pretty much got a 'rocket' which either chucks out metal or chucks out momentum into the electromagnetic field, and chances are a laser would be far more efficient at the latter as its more directional than a coil of superconductor (though thats just a guess). Its interesting, but I very much doubt its useful.
By the way, I know a lot of this post is redundant, but I thought a lot of it was worth repeating because its a confusing issue. Mod me down if you like.
I remember reading about someone elses idea for an electromagnetic thruster here
I have *no* idea if this is physically possible (or even if the website is serious :)
Surely no serious scientist actually considers Newtons theorys as actual 'Laws' ?
They're systems we use that seem to work in some cases. Every new groundbreaking discovery in physics overturns an old 'Law of physics'.
There was a time not long ago when superconductors were deemed impossible (at any temperature) yet we all now take them for granted.
oh really?
Stupid backgrounds
Umm, sorry to break you this, but this has been done already. There have been experiments done with laser light propulsion. Here's the first link that I found
http://members.nbci.com/djm1947a/laserpow.html
"We have an A-Bomb...what more do you want, mermaids?" --I.I. Rabi, speaking in defense of Robert Oppenheimer
The silly thing is just a nonlinear oscillator. John W. Campbell got all enthusiastic about this 40 years ago; it was bogus then and (the introduction of an electromagnetic component notwithstanding) conservation of momentum says it's bogus now.
I decided that behaving ethically was the most nihilistic thing I could do. - Paul Pavel
I remember on a program on TLC they had a guy who claimed he had worked with Flying Saucers. ,say, the sun, and one at ,say, the moon and the control the amount of gravitational attraction until the craft just floated there.
The basic way in whcih he explained how they work is that there were 1,2 or 3 of these tubes that had a type of machine or something that was attracted to even the slightest gravity, and could be variably controlled.
So what would happen is to float in air, they would aim one of these tubes at
Then to go fast, they would turn on their side, and 2 tubes would be aimed at a star in the same area of the sky in which they wished to travel, and one at say the Sun in order to keep them off the ground, and crank up the attraction towards that star, and off they went!
It was a very interesting show because the guy was able to explain an awful lot on how they (UFO's)
worked.
Once you're in orbit, getting other places is a lot cheaper. If we have cheap orbital shots, we'd have had a decent space station decades ago and probably explored other planets by now.
This is a common misconception, but gravity goes out to infinity. In order to reach another celestial object once in earth orbit, a certain amount of delta-v is required. For any rocket, the payload-to-total mass ratio is equal to exp(-delta-v/ve), where ve is the exit velocity.
You lose roughly half your mass just going from a geo-transfer orbit (apogee at GEO, perigee at LEO) to a circular GEO orbit. Interplanetary travel takes considerably more fuel to reach escape velocity relative to the earth. Interstellar travel requires a tremendous amount of fuel to reach escape velocity from Sol.
"1. I don't see how this would be useful for interstellar travel to the Alderon system since the vast void inbetween will a weak magnetic field if any." It would certainly be useful, assuming you could get to a decent velocity before you leave our solar system. Once you hit cruising speed, you don't need the drive. Of course, you'd better hope you don't have to stop halfway.... "2. Surely environmentalists will require us to simultaneously send a ship in the opposite direction so that we don't disrupt the sun." I think if someone were to point out to the the velocity that our sun is currently moving at, they just might figure out that it would be a moot point. Besides, in 6 months the planet would be opposite the site anyway. Why do it simultaneously?
I dont know about any of you, but I already use jolt propulsion. All that caffiene makes me run between my computer chair and the dunny during an all night coding session...
these are superconducting electrommagnets not your run of the mill ceramic magnets. It's quite possible to fields of >10T from something the size of a computer case, if you have a large current supply handy. Power isn't that much of a problem as the magnets are superconducting and therefore have no resistance. The only power loss comes from interactions between the Magnetic field and external objects
Actually it falls off with the cube of distance from it. The inverse square law only applies for monopole forces, whereas all magnets are dipoles at least