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FTL Currents May Power Pulsar Beams

kdawson posted more than 4 years ago | from the it's-the-law dept.

Space 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."

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OHNOZ (-1, Troll)

Anonymous Coward | more than 4 years ago | (#30823646)

For the lose!!!!

FTL Information? (4, Interesting)

ZeroSumHappiness (1710320) | more than 4 years ago | (#30823654)

Can we replicate this and add information to the current to transport information faster than the speed of light? (The real problem.)

Re:FTL Information? (5, Funny)

Sir_Lewk (967686) | more than 4 years ago | (#30823696)

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? (4, Funny)

NotBornYesterday (1093817) | more than 4 years ago | (#30823794)

Actually, both posts were submitted at the same time, resulting in a quantum entanglement. They were both "first post" until measured. Yours was the anti-correlated part of the singlet.

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30823862)

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.

Re:FTL Information? (4, Insightful)

tekproxy2 (1386447) | more than 4 years ago | (#30824466)

It's comments like this that keep me reading /.

Re:FTL Information? (5, Funny)

SydShamino (547793) | more than 4 years ago | (#30824514)

Yours was the anti-correlated part of the singlet.

Somehow this sounds so much better than "-1 Redundant".

Re:FTL Information? (1)

igadget78 (1698420) | more than 4 years ago | (#30824610)

Actually, both posts were submitted at the same time, resulting in a quantum entanglement. They were both "first post" until measured. Yours was the anti-correlated part of the singlet.

"Wait a tick. Basil, if I travel back to 1969, and I was frozen in 1967, presumably, I could go visit my frozen self. But, if I'm still frozen in 1967, how could I have been unthawed in the 90's and traveled back to... (cross-eyed) Oh, no. I've gone cross-eyed."

Re:FTL Information? (1)

ozbird (127571) | more than 4 years ago | (#30825246)

I got tired of the washing machine quantum entangling my singlets, so I switched to t-shirts.

Re:FTL Information? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#30823704)

Can we replicate this and add information to the current to transport information faster than the speed of light? (The real problem.)

no

Short answer (5, Funny)

jbeaupre (752124) | more than 4 years ago | (#30823706)

No.

For a detailed explanation, see the next guy's post.

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30823810)

Whenever FTL communication is discussed, quantum entanglement is usually brought up as an option. For a long time the immediate answer was "no, it can't be done", but there have been cracks in the wall lately. Google will tell you [google.com] .

Re:FTL Information? (2, Informative)

Chris Burke (6130) | more than 4 years ago | (#30824012)

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...

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30824368)

Here [esa.int] . Look for the word "instantaneously".

Re:FTL Information? (1)

Chris Burke (6130) | more than 4 years ago | (#30824474)

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 there. :(

Re:FTL Information? (2, Interesting)

derGoldstein (1494129) | more than 4 years ago | (#30824786)

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.

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 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.

If I have this wrong please correct me. This at least was my understanding of the process. It's my understanding that the distance used to be limited, which is why it wasn't realistic, but it appears that the distance is irrelevant (either that, or we haven't managed to detect any relevance yet).

Re:FTL Information? (1)

waives (1257650) | more than 4 years ago | (#30825074)

You are wrong.

Say you perform your Morse code "reaction" (actually measurement of your half of the entangled pairs). This will collapse the entanglement, and if your partner then measured their particles, they would get the exact opposite results that you got (because the particles were entangled.)

However - unless they can compare their measurements to yours, their results look exactly like random noise - and this is independent of whether or not the particles were entangled when they measured them. In other words, there is no way to detect the presence or absence of entanglement without classical slow than light communication with the hold of the other half of the entangled pair.

Re:FTL Information? (4, Informative)

Chris Burke (6130) | more than 4 years ago | (#30825078)

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.

Re:FTL Information? (5, Insightful)

camperdave (969942) | more than 4 years ago | (#30824622)

Quantum entanglement is like a coin. Once you know one side is Heads, the other side is "instantaneously" Tails.

Re:FTL Information? (4, Interesting)

Chris Burke (6130) | more than 4 years ago | (#30823856)

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? (4, Funny)

derGoldstein (1494129) | more than 4 years ago | (#30823936)

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."

Re:FTL Information? (1)

Chris Burke (6130) | more than 4 years ago | (#30824072)

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 physics at that level in even the most vague of ways.

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30824240)

'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 today.

If you want "wah wah" in regards to education, bring up classical mechanics, basic chemistry, and/or calculus.

Re:FTL Information? (1)

Chris Burke (6130) | more than 4 years ago | (#30824506)

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? (4, Informative)

hoggoth (414195) | more than 4 years ago | (#30824440)

> 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.

Re:FTL Information? (2, Funny)

SydShamino (547793) | more than 4 years ago | (#30824544)

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? (4, Funny)

hoggoth (414195) | more than 4 years ago | (#30824700)

> 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.

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30824850)

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...

Re:FTL Information? (1)

derGoldstein (1494129) | more than 4 years ago | (#30824974)

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.

Re:FTL Information? (0)

Anonymous Coward | more than 4 years ago | (#30824582)

186,000 mi/hr. It's not just a good idea; it's the law.

FTL information (1)

Sir_Lewk (967686) | more than 4 years ago | (#30823658)

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 (4, Informative)

Kagura (843695) | more than 4 years ago | (#30823758)

If you wave a laser pointer around at the moon, you can make a dot on the moon that moves faster than light. That doesn't mean your laser photons are moving faster than light.

Re:FTL information (1)

Monkeedude1212 (1560403) | more than 4 years ago | (#30823874)

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.

Re:FTL information (1)

derGoldstein (1494129) | more than 4 years ago | (#30824010)

I was going to post a very similar response:
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.

Re:FTL information (3, Informative)

poopdeville (841677) | more than 4 years ago | (#30824080)

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.

Re:FTL information (1)

blueg3 (192743) | more than 4 years ago | (#30824120)

Current doesn't necessarily involve something actually moving from point A to point B either.

Re:FTL information (1)

Monkeedude1212 (1560403) | more than 4 years ago | (#30824320)

I thought it did (which would make it a big deal)

Re:FTL information (1)

BitZtream (692029) | more than 4 years ago | (#30824876)

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.

Re:FTL information (1)

Chris Burke (6130) | more than 4 years ago | (#30824122)

That's exactly the point. There are phenomenon which appear to be going FTL, but nothing real (including information) actually is.

Re:FTL information (1)

Unequivocal (155957) | more than 4 years ago | (#30824494)

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.

Re:FTL information (1)

Sir_Lewk (967686) | more than 4 years ago | (#30823990)

Thanks, that explains it well. I guess I got hung up by not understanding what the article meant by "currents".

Re:FTL information (1)

BitZtream (692029) | more than 4 years ago | (#30824852)

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 distances, that would appear to the observer on the Earth as though it was moving faster than it actually is. When the reflection of the light from the laser returned to your eye, the line would appear as a dot again, all due to perspective of the viewer.

Re:FTL information (0)

Anonymous Coward | more than 4 years ago | (#30825144)

Wow, that's a lot of BS all in one post... ;)

Re:FTL information (4, Informative)

jbeaupre (752124) | more than 4 years ago | (#30823926)

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.

Re:FTL information (-1, Troll)

Nadaka (224565) | more than 4 years ago | (#30824068)

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.

Re:FTL information (2, Informative)

Anonymous Coward | more than 4 years ago | (#30824176)

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 (4, Informative)

Chris Burke (6130) | more than 4 years ago | (#30824212)

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.

Re:FTL information (0)

Anonymous Coward | more than 4 years ago | (#30824614)

You're all doing it wrong.

BOOBS!!!

Re:FTL information (1)

Quantumstate (1295210) | more than 4 years ago | (#30824236)

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.)

Re:FTL information (1)

derGoldstein (1494129) | more than 4 years ago | (#30824092)

Oh for heaven's sake, somebody post a car analogy!

Re:FTL information (5, Informative)

vlm (69642) | more than 4 years ago | (#30824318)

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.

Re:FTL information (2, Funny)

zztong (36596) | more than 4 years ago | (#30824536)

Well done. Pretty cool, really.

Now make an analogy using a cow, 5 bags of salt, and the Pacific Ocean. :)

Re:FTL information (1)

ArsonSmith (13997) | more than 4 years ago | (#30824538)

But can I use it to send information to my buddy at the bar about a cop pulling people over?

information faster than light? (1)

jamboarder (620309) | more than 4 years ago | (#30823670)

If the current generated is faster than light, does it imply that information carried by the current could potentially be faster than light?

Re:information faster than light? (2, Insightful)

Gravitron 5000 (1621683) | more than 4 years ago | (#30823962)

Do you have any idea how hard it is to modulate a pulsar?

Re:information faster than light? (1)

ArsonSmith (13997) | more than 4 years ago | (#30824566)

We choose to modulate a pulsar, not because it is easy, but because it is hard.

Google (2, Funny)

MillionthMonkey (240664) | more than 4 years ago | (#30823700)

Has Google filed its patent yet on "Method and Materials to Power a Pulsar Beam Using a Faster-Than-Light Current"?

Re:Google (4, Funny)

goldaryn (834427) | more than 4 years ago | (#30823796)

Has Google filed its patent yet on "Method and Materials to Power a Pulsar Beam Using a Faster-Than-Light Current"?

Not in China..

Re:Google (1)

happy_place (632005) | more than 4 years ago | (#30824984)

That's cuz China hasn't broken any laws taking what is rightfully theirs... including pulsars... There are no borders, space, fast-moving information, or claims that will keep China from justly claiming all the stars as belonging to greater "China".

Re:Google (0)

Anonymous Coward | more than 4 years ago | (#30824990)

Not in China..

as they are already manufacturing genuine FTL current powered Pulsar Beam replicas for the discerning soldier and for home protection. PulsZap, the only relativistic weapon your government trusts.

You know what else creates FTL currents? (5, Insightful)

jeffb (2.718) (1189693) | more than 4 years ago | (#30823748)

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.

Re:You know what else creates FTL currents? (1)

Chris Burke (6130) | more than 4 years ago | (#30823922)

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?

Re:You know what else creates FTL currents? (0)

Anonymous Coward | more than 4 years ago | (#30823928)

Spray a machine gun across the room. The time between impacts of the right-most bullet and the left-most will be very close, but no bullet moved laterally.

You don't need a disco ball, just a laser and the moon. You still don't get anything moving FTL.

Re:You know what else creates FTL currents? (1)

BitZtream (692029) | more than 4 years ago | (#30824982)

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? (3, Interesting)

IorDMUX (870522) | more than 4 years ago | (#30825162)

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.

Area 51 Firing At Private Pilots (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30823752)

courtesy of Art Bell [youtube.com] .

Aliens MAY exist.

Yours In Perm,
K. Trout

GJ slashdot... (1, Funny)

Anonymous Coward | more than 4 years ago | (#30823872)

GJ Slashdot for making me search for "Einsteinian post-mortem rotation" [google.com] . Well played.

Taking bets on how long it takes to come up on Google Trends.

Not the big deal people make out of it ... (5, Informative)

dougmc (70836) | more than 4 years ago | (#30823916)

[ 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.

Re:Not the big deal people make out of it ... (2, Insightful)

Anonymous Coward | more than 4 years ago | (#30824094)

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 situation to even having the appearance of FTL.

Re:Not the big deal people make out of it ... (0)

Anonymous Coward | more than 4 years ago | (#30824258)

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.)

I'm not an american you insensitive clod!

-gorsh

Re:Not the big deal people make out of it ... (1)

ArsonSmith (13997) | more than 4 years ago | (#30824414)

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)

Re:Not the big deal people make out of it ... (1)

BitZtream (692029) | more than 4 years ago | (#30825022)

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 (4, Insightful)

tylersoze (789256) | more than 4 years ago | (#30823934)

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.

Re:Here we go again (1)

blueg3 (192743) | more than 4 years ago | (#30824134)

But they can do it in Star Trek!

Re:Here we go again (0)

Anonymous Coward | more than 4 years ago | (#30824184)

Ahh - be we could compute stuff faster than the speed of light. Say a particular computer problem takes x years to compute. We take a laptop start it on the problem. We then put the earth (leaving the laptop behind) in close proximty to a black hole. Since the earch will be travelling closer to the speed of light, time will slow down for us, leaving the laptop to finish the problem and email us the result in less than x time. Idea patent pending.

Re:Here we go again (1)

snooo53 (663796) | more than 4 years ago | (#30824410)

That reminds me of Tipler's omega point theory... that when/if the universe collapses in a big crunch the computational capacity of the universe increases so exponentially that you could simulate every quantum state that ever did and ever could exist forever in the finite time before the crunch. Of course that's assuming there is a civilization still around capable of building it in the first place... http://en.wikipedia.org/wiki/Omega_point#Tipler.27s_cosmological_Omega_Point [wikipedia.org]

Perpetual motion machine theory (0, Redundant)

jbeaupre (752124) | more than 4 years ago | (#30824238)

The first law of thermodynamics is you do not talk about thermodynamics
The second law of thermodynamics is you do not talk about thermodynamics

Re:Perpetual motion machine theory (1)

Luyseyal (3154) | more than 4 years ago | (#30824396)

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...

Re:Perpetual motion machine theory (1)

derGoldstein (1494129) | more than 4 years ago | (#30824586)

i can haz thermodynamics?

Re:Here we go again (1)

NathanWoodruff (966362) | more than 4 years ago | (#30824354)

There is no reason why mass can't travel faster than light. The problem comes from what can we use to propel mass faster than the speed of light? To put this in perspective, if all you had was sound waves, could you use sound to make something go faster than the speed of sound? Kind of hard wouldn't it be?

Chemical reactions happen faster than the speed of sound and therefore can propel mass faster than the speed of sound, gun powder, Jet A, Ammonium nitrate in rockets etc... Chemical reactions do not happen faster than the speed of light, so, no go. Nuclear reactions might occur near the speed of light, but that is still a no go.

If there was some way of releasing energy faster than the speed of light, then there would be a way to propel mass faster than the speed of light. As of now, there is none.

Transferring information faster than the speed of light isn't possible, period, because we use light or electrons that travel at the speed of light to encode that information. The speed of what we use to encode information right now will never change, therefore information will never ever be transmitted faster.

Re:Here we go again (2, Interesting)

Jason Levine (196982) | more than 4 years ago | (#30825042)

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 0.999c, 22 times rest mass. And so on.

Now what happens if you go faster than light? (Supposing you somehow "skip over" the light speed barrier.) You get into imaginary numbers. For example, at 2c your mass would be MassAtRest / sqrt(-3). What does that imaginary number translate into? There are many theories, but no firm answers. The equations for velocity and time are similar so some theorize that it means going back in time. Others say the imaginary numbers mean it just can't be done. Still others think that this just shows where relativity breaks down and a new set of equations is called for.

Re:Here we go again (1)

Fantastic Lad (198284) | more than 4 years ago | (#30824468)

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 like this, and it would appear to us as though it were traveling a great distance.

Or something like that.

Like I said. I am not a physicist, but you hear stuff, you know? And one of the things I've heard is that Einstein's theories were furthered but kept very quiet. There have been some very weird deaths among physicists.

-FL

Re:Here we go again (2, Interesting)

bcrowell (177657) | more than 4 years ago | (#30824810)

Your post is basically on the right track, but some thing you say are not quite right.

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.

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 suspect that cause and effect can't be propagated at velocities greater than c in flat spacetime.

In curved spacetime, this is far from being established. General relativity has spacetimes, such as the Godel solution, that are valid solutions of the field equations, and that violate causality. Hawking's chronology protection conjecture says that this kind of causality violation can't arise from realistic conditions in our universe -- but that's all it is, a conjecture. Nobody has proved it. In fact, there is a major current research program that consists of nothing more than trying to *define* rigorously what the chronology protection conjecture means.

Physics develops from what proceeded it, from Newton to Einstein to Quantum Mechanics to String Theory, and those conservation laws always held.

Okay, but the prohibition on transmission of cause and effect at velocities greater than c isn't a conservation law.

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.

I think the analogy here would be the following. Even the slashdot summary makes it clear that they aren't really claiming propagation of information at velocities greater than c. That's also reasonable, because although a neutron star is a relativistic object, it's not all that highly relativistic. Its structure is complicated from a nuclear physics point of view, but from the point of view of the relativistic description, it's a very plain vanilla solution of the Einstein field equations. If information was going to be transmitted at greater than c, then the chronology protection conjecture would also be violated, but that's not going to happen in such an ordinary, well studied spacetime.

It is not safe to use your criterion to rule out examples from general relativity without more attention to the details. Based on your criterion, the Godel spacetime has to be a crackpot idea, and so is the Alcubierre drive. In reality, there is a clear consensus among relativists that the spacetimes found by Godel and Alcubierre are correct -- it's just not clear how to interpret them, or whether they could actually arise from realistic conditions in our universe.

Re:Here we go again (0)

Anonymous Coward | more than 4 years ago | (#30825238)

What if you created a pocket of space and propelled the pocket faster than light? Where everything in the pocket would be standing still.

Or better yet, the presence or non presence of the FTL stream could be encoded information.

It's all relative. (0)

Anonymous Coward | more than 4 years ago | (#30824056)

Suppose you build a railroad track that goes all around the planet. Suppose you've got a train that's the same length as the track, with a track on top of it.

Now, stack up that same model until you have one dozens layers. Now suppose each train never goes above 1/10 of the light speed. The top train, however, will be moving faster-than-light relative to the ground.

I'm from the future! (1)

rehtonAesoohC (954490) | more than 4 years ago | (#30824074)

I have come back in time using the faster than light technology developed from pulsar beams in the year 2010 to tell the world NOT TO DEVELOP THE TECHNOLOGY!

Everyone just zips around everywhere and the infrastructure of the world crumbles. Don't let it happen to you!

Preventing Einsteinian post-mortem rotation, eh? (1)

rebelscience (1717928) | more than 4 years ago | (#30824118)

This is a falsifiable hypothesis. Does anybody know where Einstein's grave is? I would like to conduct a skeleton rotation experiment.

Re:Preventing Einsteinian post-mortem rotation, eh (1)

kevinNCSU (1531307) | more than 4 years ago | (#30824332)

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:Preventing Einsteinian post-mortem rotation, eh (1)

rebelscience (1717928) | more than 4 years ago | (#30824738)

Bummer.

It's the Medium (2, Interesting)

rebmemeR (1056120) | more than 4 years ago | (#30824222)

We know the speed of light in some mediums is less than c (see cherekov radiation). Is it possible the speed of light is greater than c in some mediums? You have to admit that a neutron star is pretty exotic stuff. What about negative-index metamaterials? Beyond that (and this may be non sequitur) maybe a concentration of "dark energy" has properties we don't understand.

Replies to the thread vs. Time (2, Interesting)

Anonymous Coward | more than 4 years ago | (#30824248)

It's interesting to watch as the /. crowd's replies to the technical question in the post become both less succinct and more smarmy as you get further down the comments. I have not yet attempted to correlate this phenomenon to user id number.

Re:Replies to the thread vs. Time (4, Funny)

natehoy (1608657) | more than 4 years ago | (#30824672)

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.

AAS, not AAAS (2, Informative)

complex.confusion (1724982) | more than 4 years ago | (#30824404)

FWIW, this is from the American Astronomical Society (AAS), not the American Association for the Advancement of Science (AAAS). One of my more frequent typos.

More like... (1)

SirTicksAlot (576078) | more than 4 years ago | (#30824512)

FTW!

Rigid Carbon Nanotube!!! (1)

jameskojiro (705701) | more than 4 years ago | (#30824520)

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?

Re:Rigid Carbon Nanotube!!! (0)

Anonymous Coward | more than 4 years ago | (#30825090)

Unfortunatly the far end will also be droping frames. wich will break the carbon rod.

Re:Rigid Carbon Nanotube!!! (1)

srollyson (1184197) | more than 4 years ago | (#30825114)

There's three possibilities:

  • It will be too thick and you won't be able to swing the other end 'round.
  • It will be too thin and it'll snap where you're holding it.
  • It will be just the right thickness to cut your hand in half.

You don't want Goldilocks to be an amputee, do you?

Re:Rigid Carbon Nanotube!!! (1)

Khashishi (775369) | more than 4 years ago | (#30825218)

Anything solid thing 1LY long is very easy to break. If you try to rotate it, you will break it.

Now if we could .... (1)

b12arr0 (3064) | more than 4 years ago | (#30824624)

find a mass relay.

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