FTL Currents May Power Pulsar Beams 236
thomst passes along news out of the recent AAAS meeting of a new explanation for pulsar beams that involves faster-than-light currents. Here are Los Alamos's press release and three related papers on the arXiv. "The new model explains the beam emissions from pulsars as products of superluminal currents within the spinning neutron stars' atmospheres. According to the authors' model, the current generated is, itself, faster than light, although the particles that compose it never individually exceed the universal speed limit, thereby preventing Einsteinian post-mortem rotation. The new model is a general explanation of the phenomenon of pulsar beam emissions that explains emissions at all observed frequencies (and different pulsars emit everything from radio waves to x-rays), which no previous model has done."
FTL Information? (Score:4, Interesting)
Re:FTL Information? (Score:5, Funny)
Clearly you have already perfected this FTL information transmission and used it to get a firstpost with a topic uncanningly similar to mine. ;)
Re:FTL Information? (Score:5, Funny)
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Actually, both posts were submitted at the same time, resulting in a quantum entanglement.
And my post about quantum entanglement was posted (according to the log, at least) 1 minute after yours, so while we probably typed at the same time, my post arrived at its destination a few seconds later, making it a clear case of slower-that-light, psychic phenomenon.
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Re:FTL Information? (Score:4, Insightful)
Re:FTL Information? (Score:5, Funny)
Yours was the anti-correlated part of the singlet.
Somehow this sounds so much better than "-1 Redundant".
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Unfortunately, the cat is dead.
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The difficult thing about being a quantum comedian is that your jokes are both funny and unfunny at the same time.
Short answer (Score:5, Funny)
No.
For a detailed explanation, see the next guy's post.
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Uh... do you have any links to these "cracks in the wall"? Because the first couple pages of search results all just show the standard descriptions about why quantum entanglement isn't FTL communication...
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Bah, that's the same stuff as always. Yes the other half of the entangled pair changes instantaneously, but you still can't use that to send information. You'll notice that in the next paragraph they discuss actual applications and it's the usual quantum crypto-channel stuff where you can use entanglement to detect eavesdroppers. Nothing about actual FTL information transmission, because this is the same ol' entanglement as every other link on google describes.
You almost had my hopes up for a minute ther
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Ok, I know the following will sound like a "loophole", but we need to define "transfer of information" here. If I send a batch of particles a light-year away in a certain direction, and then "store" them (prevent them from interacting), then I've created the potential for faster-than-light communication. The
Re:FTL Information? (Score:5, Informative)
Yeah, it *is* the same stuff as always, it's only the distance that changed. It was theorized that the particles could *not* remain entangled for nearly that distance -- that makes all the difference.
It makes a huge difference as far as practical quantum communication channels -- which are "merely" secure channels where any attempt to eavesdrop on the sub-light information stream can be detected -- but zero difference as far as the theory of whether or not it can be used for FTL info transfer, which still remains a big "no".
The particles, once they reach their destination, will be under constant observation. When I want to send a signal, I make the particles on my end "react" in a pulse-width-modulation fashion, like Morse code. Their corresponding particle pairs on the other end will "untangle" at the same rate, but instantaneously.
The reason this doesn't work is that for the person on the other end to detect that the particle in their possession has become untangled, they have to interact with it which would destroy any entanglement were there to have been any. In other words, there is no way for them to tell the difference between the waveform collapsing because you made it collapse versus them making it collapse by checking to see if you made it collapse.
The only thing they know is that there is a correlation between whatever state they observe in the post-collapse particle and your particle... but they knew about that correlation when you gave them their particle to carry away with them at sub-light speed in the first place. All actual information was carried with the particles themselves at sub-light speeds.
Those links from the google search can provide more explanations, too. Suffice to say that all known methods of using quantum entanglement -- whether for communication, or "teleportation" -- involve things moving at sub-light speeds.
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Ok, I was wrong, but I will make a last-ditch effort with my now updated knowledge:
I have my batch of entangled particles here, and the other "side" has their batch of entangled particles many millions of kilometers away. There's an agreed upon time in which to check the state of the particles (on their side). Before the aforementioned time arrives, I flip the the particles on my en
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Humm... no.
You don't flip your particles. You just measure them. You can't determine the outcome. With this in mind, the information you obtained is no more FTL than if each had pre-correlated deck of cards.
What is mysterious in quantum entanglement is that this correlation is kept regardless of which base you measure: this can't be done with a deck of cards.
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Before the aforementioned time arrives, I flip the the particles on my end. I now "Know" what the state of the particles on the other end will be, even though the other side couldn't possibly send me that information *after* they've checked the states, at that speed.
Isn't that information in and of itself, which arrives faster than light?
No, it's information that arrived with the entangled particle itself.
See, the knowledge that whatever state you eventually observe in your particles the other side will see
Re:FTL Information? (Score:4, Informative)
Are you kidding? Many people did love and would love the idea of hidden variables! It'd be like telling the children there most certainly are presents in the closet, but presents they can know nothing about and must not peak. The kids would be angling for their first chance to get in there.
Hidden variables would mean a deeper understanding of which we are ignorant - fun stuff to keep chasing down.
No, it's not that Quantum Physicists just don't like Hidden Variables.
It's that a pretty clever chap figured out a way to test whether Quantum Physics involved Hidden Variables (without really needing to know much about them). Once he (and a few others) refined these ideas and actually did some tests, the results were clear. And as our instrumentation gets better over time, similar testing has more and more profoundly demonstrated Quantum Physics simply does not depend on Hidden Variables - it's just that weird.
Look up Bell's Theorem.
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Yeah, it *is* the same stuff as always, it's only the distance that changed. It was theorized that the particles could *not* remain entangled for nearly that distance -- that makes all the difference.
There was never a theoretical upper bound on the distance within each particles could remain entangled. See the original EPR paper.
What happened recently was an experiment which showed quantum teleportation through a large distance. Which is great, but expected.
Re:FTL Information? (Score:5, Insightful)
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Observing the entangled particle is like flipping the coin. If it comes up heads, you "instantly" know tails is down.
Re:FTL Information? (Score:5, Interesting)
Can we replicate this and add information to the current to transport information faster than the speed of light? (The real problem.)
Well I'm going to say no simply based on the fact that they are claiming no physical laws are being broken and that Special Relativity is not violated, since super-luminal information transfer = time travel = causality violation = impossible in SR. This not the first time this effect has been proposed and it has apparently been studied in labs, so if it was a possible way to transmit information, it seems they would have probably figured that out by now and at least some aspect of SR (perhaps causality!) would have to be scrapped.
I don't fully understand what they're talking about, but it sounds like a similar phenomenon to group velocity [wikipedia.org], in which some aspect of the wavefront can be said to be traveling faster than light, but nevertheless real photons and information cannot.
Re:FTL Information? (Score:5, Funny)
no physical laws are being broken and that Special Relativity is not violated
You know there's a problem with the world when someone has to *explicitly clarify* that Special Relativity isn't being violated.
I can see the signs that will replace "no smoking" 20 years from now: "This is a physics-abiding zone, please do not exceed light speed. Thank you."
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Lisa! In this house we obey the Laws of Thermodynamics!
But yeah, you're right in one sense, but in another, when all most people know about Relativity* is that you can't go faster than light, it makes sense to at least mention that when you're describing an FTL effect that you aren't talking about up-ending physics and that these scientists aren't crackpots.
* On the one hand, wah wah the level of education, on the other, it's kinda amazing in a historical sense that 'normal' people are even aware of physic
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'normal' people
This is Slashdot. Don't get carried away.
wah wah the level of education
I don't think that this is really a proper gauge of anyone's education. I mean, yeah, the abstract concepts aren't difficult to understand, but this isn't something that would come up in a practical sense for more than (I'm guessing) about 10,000 people on earth, and you can't really expect people to remember something like this even if they *have* studied it (and were possibly tested on the material), with everything you have to keep in mind to live in this world to
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That was exactly my point. The fact that people have even heard of Relativity and the universal speed limit is pretty amazing as far as I'm concerned.
The "wah wah" was supposed to be you, lamenting that we need to explicitly state that the laws of physics aren't being broken. ;)
Re:FTL Information? (Score:5, Informative)
> it's kinda amazing in a historical sense that 'normal' people are even aware of physics at that level in even the most vague of ways
Have you spoken to any 'normal' people lately?
Normal people think 'Ghost Hunters' is a documentary.
Normal people believe computers can think, and wouldn't like robots in their town because of the danger of them revolting against humans.
If I ask my parents what Einstein did, they say he invented the atom bomb.
My next door neighbor asked me to not let my kids use computers between 7pm and 8pm because she doesn't want them to be able to watch her in the bath (wtf?).
Don't mistake common knowledge on Slashdot for knowledge that is common.
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My next door neighbor asked me to not let my kids use computers between 7pm and 8pm because she doesn't want them to be able to watch her in the bath (wtf?).
Did you check your computer room for an unobstructed view of her bathroom? Perhaps she should install better curtains.
Re:FTL Information? (Score:5, Funny)
> Did you check your computer room for an unobstructed view of her bathroom? Perhaps she should install better curtains.
I can't tell from here, my telescope is blocking the view.
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My next door neighbor asked me to not let my kids use computers between 7pm and 8pm because she doesn't want them to be able to watch her in the bath (wtf?).
Well obviously she set up a qik stream. I'd look it up if I were you...
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Normal people think 'Ghost Hunters' is a documentary.
Why, what did you think it was?
Normal people believe computers can think, and wouldn't like robots in their town because of the danger of them revolting against humans.
Actually the possibility that robots/computers will rebel against humans is plausible (even if "rebel" may be the wrong word). I know you mean that "they" think about it in a different way than you do, but I think that particular example isn't a good one -- we've all seen Terminator.
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Re:FTL Information? (Score:4, Insightful)
FTL information (Score:2)
It was my understanding that information in general cannot exceed the speed of light. Is this not the case, or do FTL currents somehow not transmit data FTL?
Re:FTL information (Score:5, Informative)
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It also doesn't mean anything is actually moving from point a (Where the laser pointer first hits) to point b (Where the laser pointer last hits).
You are playing the illusionist there.
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This would be the equivalent of pointing a water hose at the moon and waving it around so that the theoretical points of impact would "move" faster than light, except that you're really shooting particles in different directions at (nearly) the same time. Basically you're firing a gun at one pole, then moving it quickly and firing it at another pole -- they're not the same bullet.
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It's light... it's a big wave, with its source at your laser.
The real solution to this "problem" is that you can't transmit information from point A to point B faster than light, despite the fact that the beam can change focus between A and B, faster than light. You can use the triangle inequality to show this.
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Current doesn't necessarily involve something actually moving from point A to point B either.
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I thought it did (which would make it a big deal)
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Uhm, thats funny, it would seem that every person on the planet with a basic understanding of electricity is wrong then.
Electrical current is the movement of electrons between atoms, it most certainly involves movement of electrons.
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Electrical current is the movement of electrons between atoms, it most certainly involves movement of electrons.
Electrical current is the movement of sources/sinks of the electric field. No atoms required.
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You're describing an electrical current -- although it bears pointing out that a current between A and B does not involve any electrons actually moving from A to B, but moving only very small distances.
These, on the other hand, are polarization currents. Every person on the planet capable of reading the linked article could know that.
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That's exactly the point. There are phenomenon which appear to be going FTL, but nothing real (including information) actually is.
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Indeed. We could use another analogy (cars of course). If I turn the headlights off on my car at the exact same time (to an observer) as someone in China turns on their lights, we wouldn't say that the "headlights" moved faster than light, moving from my car to his car. Ditto for a laser pointer moving around on the moon.
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Thanks, that explains it well. I guess I got hung up by not understanding what the article meant by "currents".
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No, it doesn't work that way, thats a typical misunderstanding of the way it works because you're confusing observations from your perspective with reality.
The dot isn't moving at all, and you wouldn't actually have a dot painted on the surface of the moon. From your perspective on Earth it may appear that way, but appearances are often deceiving.
What you end up with is something that would resemble a dimmer (than the dot would be if stationary) line or blur on the surface of the moon, spread out over vast
Re:FTL information (Score:5, Informative)
Sort of.
Try this for an analogy: imagine a circular wall around us located one light-year radius away. Point your laser pointer at the wall, then sweep it so that it points to another spot 1 light year away on the same wall. Do that in 1 second.
1 year later, a dot of light will appear on the wall. The dot will then exceed the speed of light, traveling 1 light-year in 1 second. If that dot also induced an electric charge, it will look like some sort of current pulse just traveled along the wall millions of times the speed of light.
So, you've created a current, faster than the speed of light, that appears to carry information FTL, but not in a meaningful way.
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Reading -- you're doing it wrong.
Point your laser pointer at the wall, then sweep it so that it points to another spot 1 light year away from the first.
1 light year = 1 light year
The angle swept was 1 radian, not Pi radians.
Re:FTL information (Score:5, Informative)
Maths. You are doing them wrong. The point of light will not travel 1 light year in one second. It will travel Pi light years in one second as it traces out a half circle with a radius of one light year. If you meant to indicate the linear difference, that is also wrong, it would have been 2 light years.
Reading: You're doing it wrong.
They did not say he was rotating the light source by pi radians. They said they were rotating the source so that it struck a point 1 light year from the original. The arc-length -- or linear distance, either way -- was in the statement of the problem. If you want to do maths, then you can work your way backwards to the total angular displacement and angular velocity. Your answer will be different depending on whether they meant a circular wall or a flat wall, but either way the statement of 1 year of displacement is not wrong and cannot be wrong.
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Ah no you have made an invalid assumption. You are thinking that he was measuring distance in cartesian space. What he said was "1 light year away on the same wall" which clearly implies that he was measuring distance using a geometry based on the wall. (Also your maths fails in cartesian geometry because he never said that the pointer described a semicircle so in fact a line between the two points would be a chord of the circle on length 1 light year.)
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Re:FTL information (Score:5, Informative)
Oh for heaven's sake, somebody post a car analogy!
Take yer hotrod up to about 25 MPH at night and spin some donuts. From far enough away, the headlights reflecting off the walmart wall will move way faster than 25 MPH, maybe 1000 MPH who knows.
Now does the cop give you a ticket for speeding because your headlight reflections are moving 1000 MPH? No, nothing was speeding. The reflection is just a mathematical construct that means nothing. The cop gives you a ticket for being a dumbass and disturbing the peace, not for speeding.
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Well done. Pretty cool, really.
Now make an analogy using a cow, 5 bags of salt, and the Pacific Ocean. :)
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Now make an analogy using a cow, 5 bags of salt, and the Pacific Ocean. :)
A cow, 5 bags of salt, and the Pacific Ocean are in a car doing donuts...
Re:FTL information (Score:4, Funny)
Now make an analogy using a cow, 5 bags of salt, and the Pacific Ocean. :)
So, near Hawaii, we have a cow and 5 bags of salt. Force feed the salt to the cow, which promptly dies (sorry PETA). The rotting cow corpse expands and finally detonates (sorry cDc), at, for example, the speed of light. Flaps of leather strike SFO, nothing unusual, but it is odd that they strike LA at about the same time. Scientist watching from a satellite says its as if leather was smeared in a line thru SFO and LA however the line must have moved at about a zillion times the speed of light, like the Enterprise had an accident while transporting some steers at full warp speed. No, scientist has it wrong, because the direction of motion is actually perpendicular to the line between SFO and LA, the motion was actually from Hawaii at merely light speed.
The difference in time of impact and distance between SFO and LA are just a math abstraction which by no means implies the leather moved along that path at a zillion times the speed of light.
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Well done. Pretty cool, really.
Now make an analogy using a cow, 5 bags of salt, and the Pacific Ocean. :)
Assume a spherical cow in a vacuum...
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But can I use it to send information to my buddy at the bar about a cop pulling people over?
Google (Score:3, Funny)
Re:Google (Score:5, Funny)
Has Google filed its patent yet on "Method and Materials to Power a Pulsar Beam Using a Faster-Than-Light Current"?
Not in China..
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You know what else creates FTL currents? (Score:5, Insightful)
A disco ball. Shine a light on a disco ball, and project those cool reflections onto a surface more than a few light-seconds away. You'll see that the spots move much faster than light.
Still no FTL movement or information transfer. Still no violation of GR or causality. Just another nice, attention-grabbing headline.
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A disco ball. Shine a light on a disco ball, and project those cool reflections onto a surface more than a few light-seconds away.
Yep. I like the analogy of pointing a laser pointer at the moon and wiggling it back and forth really fast.
Still no FTL movement or information transfer. Still no violation of GR or causality. Just another nice, attention-grabbing headline.
Yeah but even the summary explicitly says there's no violation of Einstein's theory, so what's yer point?
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The spots won't be moving faster than light, they will actually be a blur or line spread across the surfaces they hit.
You're confusing perception with reality, and they are two very different things.
Re:You know what else creates FTL currents? (Score:4, Interesting)
The spots won't be moving faster than light, they will actually be a blur or line spread across the surfaces they hit.
You're confusing perception with reality, and they are two very different things.
I think the GP was right, any you may have it backwards. The human eye will perceive a blur or line, due to the limited "frame refresh" and averaging of our optical system. In reality, though, the "spot", as defined by the location where the photons are hitting/reflecting from the surface, will be traveling faster than light. No information can be conveyed, however, as no point on this surface can directly use this phenomenon to actually communicate anything faster than light.
Not the big deal people make out of it ... (Score:5, Informative)
[ I'm referring to the concept of seeing something that moves faster than the speed of light, not anything else here, just so it's clear ]
Consider this situation --
You've got a big sphere. Let's say it's 93 million miles in radius (the size of our radius around the sun -- it's a figure we're all familiar with anyways.)
In the middle of this sphere is a man. He has a laser, and he's shining it on the sphere. Since the man is still, the laser is not moving.
But, then the man starts spinning, once per second. The laser takes about 8 minutes to reach the edge of the sphere, but once it does, the dot starts going around the outside of the sphere, once per second. If you do the math, that means the dot is moving 584,000,000 miles per second -- which is about 3100 times the speed of light.
The light from the laser is still going at the speed of light, but the dot appears to be moving at over 3000 times the speed of light. But it's just a location -- the spot that the laser is hitting right now -- it doesn't mean that something tangible is exceeding the speed of light, and therefore Einstein isn't proved wrong by it.
My point is, it doesn't require some really strange neutron star situation to picture a situation where something might appear to be traveling faster than the speed of light.
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The laser has energy density. Take the machine gun example, again. If a machine gun is spun fast enough, there might only be two bullet holes, the left-most and the right-most. The same with the laser. If you want to see a spot that has continuous brightness reflected back, you will have to sweep it very slowly. This is physical phenomena. There is no magic laser that reflects back the same intensity no matter how fast it gets swept across a surface.
I think there really does have to be a remarkable situatio
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Bad poster!
No Car analogy.
Although I can't come up with much other than holding a gas pump and spinning in a circle. (Don't try this at home)
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What you get on that outside wall wouldn't be a spot generated by the laser, at that point the 'spot' would appear (if you were on the wall, and not at the sun) as a line due to the beam being spread out by your turning around in circles.
This is all just a matter of perspective and is otherwise nothing new. The laser beam isn't projecting a 'dot' when its moving, even though most of the time it is perceived as such.
Here we go again (Score:5, Insightful)
Ah yes it's time again to break out the old phase vs group velocity explanation again. There are plenty of things that can go "fast than light", but repeat after me, you cannot transmit *information* faster than light. There are many concepts in our current understanding of physics that you just take to be inviolate like conservation of energy, momentum, speed of light. That's not to say we those concepts might eventually be superseded but as a general rule of them any theory that doesn't follow them is probably pseudoscience and wrong. Physics develops from what proceeded it, from Newton to Einstein to Quantum Mechanics to String Theory, and those conservation laws always held. Perhaps reformulated in a different manner to stand for different things but they still held. You don't need to know the details of how a proposed "perpetual motion machine" may work to know that if the crackpot building it says that it violates the law of conservation of energy then it doesn't work.
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But they can do it in Star Trek!
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I am not a physicist, but you hear things, you know. . ?
I'm not altogether clear about all this talk regarding so-called, Quantum Entanglement. It doesn't sound as though there is anything being transmitted at all.
Or, just blowing smoke off the top of my head. . , what if two points on, say, a 10 dimensional object appear in our space to occupy two distant locations, but which are in fact part of the same object. If you move one point, the other moves instantaneously. Information could be transmitted lik
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Your post is basically on the right track, but some thing you say are not quite right.
Well, not quite.
In flat spacetime, velocities greater than c lead to violations of causality: observer 1 says that event A caused event B, but observer 2, in a different state of motion, says that B caused A. Since violation of causality can produce paradoxes, we s
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> and those conservation laws always held.
Sort of. Conservation of energy has only held by redefining what "energy" means to include mass (and the separate law of conservation of mass was summarily dumped). Energy and momentum conservation is obviously only true as long as you work in a particular inertial frame (whereas the whole thing with the speed of light is that it seems to be invariant across all reference frames).
But more importantly, the reason you get things like conservation of momentum is t
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All your thermodynamics are belong to us?
Let's discuss the thermodynamics of hot grits in Natalie Portman's pants.
o/~ I just want to tell you how I'm feeling o/~
In Soviet Russia, thermodynamics doesn't talk about YOU.
Any other memes care to chime in?
-l
/sorry...
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It's not so much needed a better system of propulsion. It's that, as you approach light speed, your mass increases. This means you need more fuel to push yourself faster. This more fuel increases your mass, which is still increasing exponentially as you get closer and closer to light speed.
The exact formula is:
M = MassAtRest / sqrt(1 - (v/c)^2)
At 0.5c, your mass would be about 1.3 times your rest mass. At 0.9c, you'd be nearing 2.3 times rest mass. At 0.99c, you'd have passed 7 times rest mass. At 0.9
I'm from the future! (Score:2)
Everyone just zips around everywhere and the infrastructure of the world crumbles. Don't let it happen to you!
It's the Medium (Score:2, Interesting)
Replies to the thread vs. Time (Score:2, Interesting)
Re:Replies to the thread vs. Time (Score:5, Funny)
As General Relativity tells us, information cannot travel faster than the speed of light, and the closer you get to the speed of light the more energy you need. I'm a civilian, so I don't usually have to obey generals, but this Relativity dude seems to speak with some authority, so I'll listen to him.
Anyway, it's also pretty inherently obvious that theoretically infinite amounts of information can be kept perfectly still with no energy expended. You just need a stable medium.
It stands to reason, therefore, that there is an inverse relationship between the speed of an object and the amount of information that may be carried on that object with a given energy input.
As a thread accelerates, the amount of useful information that can be put on it decreases. Eventually, it reaches a velocity called the "speed of blight" where the number of informationless posts like this one exceeds those with useful information.
Also, as objects move, they are affected by exterior forces, such as chaotic movement, gravity wells, etc, and that effect is proportional to the amount of force applied, and inversely proportional to the speed of the object being affected. This is why a troll (known to hang out at gravity wells, and may in fact cause them) can have a more diversionary effect on a thread when it has yet to gain velocity - the troll's black hole has more mass relative to the velocity of the thread. As the thread reaches speed, the troll can (at best) tear a small chunk off the thread and scatter it, because the thread is moving too quickly but also lacks the information necessary to maintain its integrity any more.
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As a thread accelerates, the amount of useful information that can be put on it decreases. Eventually, it reaches a velocity called the "speed of blight" where the number of informationless posts like this one exceeds those with useful information.
Does this happen before, or after Godwin's law takes effect?
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AAS, not AAAS (Score:2, Informative)
Rigid Carbon Nanotube!!! (Score:2)
Take a Rigid Caron nano-tube that is one LY long and firmly grasp one end and wave it around wildly, the far end of it will be travelling FTL!!!!
Of course how heavy is a 1LY long rigid carbon nanotube?
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Anything solid thing 1LY long is very easy to break. If you try to rotate it, you will break it.
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Wouldn't a rigid carbon nanotube be a very thin and low mass inanimate carbon rod?
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Well, 1LY is 9.4605284 × 10^15 metres and carbon nanotubes have, on average, a density of approx 1.4g/cm^-3. Assuming a 1cm radius tube, you're looking at a volume of 2971946650295cm^3 which gives you something like 4,160,725 tonnes.
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You just proved that there isn't such a thing as a rigid body. There is this upper limit, imposed by relativity.
You can make some calculations, about the electric pulse propagating through the matter at light speed, but they're trivial and boring.
the thing that gets me (Score:2)
I'm promoted to the status of god-like observer. I'm looking down on the solar system perpendicular to the ecliptic, i.e. I'm watching earth circle the sun. Using my magic powers of awesome I wink the sun out of existence. With my magical omniscient eyes I will see the Earth continuing to orbit something that no longer exists for the eight or so minutes it takes for light to move from the sun to the earth. At the time the last ray from the sun hits Earth, the sun's gravity will be cutting out. That's becaus
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We choose to modulate a pulsar, not because it is easy, but because it is hard.
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This is a falsifiable hypothesis. Does anybody know where Einstein's grave is? I would like to conduct a skeleton rotation experiment.
Einstein's brain was removed for study and his body was cremated and the ashes spread by a river in New Jersey. The skeleton rotation hypothesis is therefore certifiably false.
Re: (Score:3, Interesting)
Ok, back to physics 102.
This is where you need special relativity. Nothing can move faster than the speed of light relative to anything else, regardless of what reference frame the observer is in. If each train is traveling 1/10c relative to the train below it, an observer on the ground will see the twelfth train traveling at 0.869c.
Also, due to length contraction, if the first train was long enough to reach around the globe when stationary, it will be some 200 km too short when traveling at 0.1c, each su