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http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/08/16/scispeed116.xml


'We have broken speed of light'
By Nic Fleming, Science Correspondent
Last Updated: 12:01am BST 16/08/2007


A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time.

According to Einstein's special theory of relativity, it would require an infinite amount of energy to propel an object at more than 186,000 miles per second.

However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory.

The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of prisms that had been moved up to 3ft apart.

Being able to travel faster than the speed of light would lead to a wide variety of bizarre consequences.

For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.

The scientists were investigating a phenomenon called quantum tunnelling, which allows sub-atomic particles to break apparently unbreakable laws.

Dr Nimtz told New Scientist magazine: "For the time being, this is the only violation of special relativity that I know of."
 

While I'll wait for the research to come in and be verified, this sounds plain stupid:

No. He would arrive before people /saw/ him leave, assuming you could get around the fact that an astronaut is not a microwave photon. It's not time travel, it's fast travel, more like sound vs light. Now it would be light vs ludicrous speed.

They probably just screwed up their math or something, until someone else verifies it the world is still flat God damn it.

How would you even measure something like that, since it only has to go three feet it would already be "instantenous".

How is this different from what they did 7 years ago when they exceeded the speed of light:

The url is really long so I made it shorter! (http://pqasb.pqarchiver.com/washingtonpost/access/56660146.html?dids=56660146:56660146&FMT=ABS&FMTS=ABS:FT&date=JUL+20%2C+2000&author=Curt+Suplee&pub=The+Washington+Post&desc=The+Speed+of+Light+Is+Exceeded+in+Lab%3B+Scientists+Accelerate+a+Pulse+of+Light&pqatl=google)

The sped up light itself. Gutboy's article talks about pushing microwaves photons faster than light.

We're still at least a few days from matter transportation and warp speed though :)

Still waiting on my holodecks.


Then, finally, D&D might be cool.



Also, pr0n will make a Killing.

Negative.  It would still be LARPing, and solo LARPing is worse than multiplayer LARPing.

But if we can get them to LARP faster than the speed of light, we won't be able to watch stupid YouTube clips anymore.

It sounds stupid, but that's what the math suggests; if you travel faster than light, you would go backwards in time.  Relativity includes the idea that the faster you go, the slower time progresses for you.  So if you left Earth travelling at 0.5c, flew out for a month then back again, people here would say it took you longer than a month.  If you were to go at the speed of light (and use infinite energy in the process), time stops.  Going faster than light would then, following this pattern, reverse it.  That's why they say you can't go faster than light; it doesn't make sense.  

Dammit, Roac, you beat me to it.

I will have to be content with adding this link (http://www.vttoth.com/LIGHT/light.htm), which provides what seems to be to be a pretty decent explanation.  Most of the math on there is a bit dense, but if you're willing to just accept that the speed of light is a constant in all frames of reference, you can skip down to the bit labelled "special relativity" and end up at the Lorentz transform:


So the passage of time is unchanged "at rest", approaches a full stop as you approach the speed of light (c), and would become an imaginary number if you actually surpassed the speed of light.

Chewbacca is a Wookiee, and he lives on Endor.  That.  Does not.  Make sense.

Basically this, and experiments like this, don't really demonstrate something going faster than light.  You can take a flashlight and shine it on something far away.  Flick your wrist back and forth, and watch the spotlight move; the spot can move much faster than light, but it's not not anything in itself.  The spot can move from A to B faster than light, but information was not sent from A to B; it was sent from the flashlight to A and then from the flashlight to B.  So far, these sorts of "faster than light" tricks are just that; different variations on this sort of theme, but where in fact information isn't going from A to B faster than light.  Researchers badly want to show that they did break this rule, because it would be quite the feat; it would mean very fundamental things we know, are instead wrong.

On a side note, there is one special case where you really can break the speed of light.  Well, sort of.  It's called chernokov (or something... I can't find it because I'm spelling it badly.  Help) radiation, where particles travel faster than light in a medium.  Since light slows down as it goes through stuff, like water or glass, it means there is an opportunity for physical particles to go faster than that.  Not faster than c (light in a vaccum), just faster than light in that stuff.  It's  neat trick - makes water glow.  Sort of like a sonic boom, but with light.

 :google:

(http://img529.imageshack.us/img529/8914/lolgoogleev9.png) (http://www.google.com/search?q=cherenkov+radiation)

 :roll:

The cool thing about Cherenkov radiation is that it's been used in neutrino detectors like  Super-Kamiokande (http://neutrino.phys.washington.edu/~superk). It uses about 13,000 photomultiplier tubes to track the flashes of blue light created when an electron neutrino passes through the  water tank.  IIRC it was the first detector that was able to measure the direction of neutrinos, instead of just a detecting that one had passed through.

If you're interested in this type of thing, "Timemaster" by Robert L. Forward (http://en.wikipedia.org/wiki/Robert_L._Forward) (also wrote Dragon's Egg/Starquake, about life on a neutron star) is an interesting hard science fiction novel that extrapolates some of the precepts of instantaneous travel--and it does (according to his research, based on several theoretical papers) imply time travel.

Supplemental reading : FTL Travel:The Realities of an SF Cliche (http://www.sff.net/people/brian_a_hopkins/ftl.htm)

Forward's main conjecture was the construction of Morris-Thorne (MT) spherical wormholes via projected properties of negative matter.

I love science, but I'm an easy explanation guy. I'd say we have a better understanding of photonics than we do of time mechanics. That's why it doesn't make sense. I could comprehend things moving faster than the speed of light, as light is just another property of the universe. Why couldn't there be properties we don't comprehend that could move faster? I'd imagine it won't be people for a long. Damned. Time. But that's because we're meatbags, not some new high-speed energy particle that can be transferred in new ways.

But time? I'd be a bad science lover to say it wasn't possible to reverse. But I'd put that at the end of a loooong line of hypothesis, because it's utterly nonsensical and goes against everything the universe has shown us thus far.

And since people have brought scifi into it, here's an easy one. If there is a way to time travel, why aren't there people from the future here?

Maybe it's just like TV, or they be here, can see, but not influence. Imagine how that life would be if it were invented. Religions would crumble overnight. Remember, a few seconds ago is still the past; People would be able to see what was going on anywhere, with just a slight delay. What a world that would be. The only way that I would be willing to give up my pivacy is something like that, where everyone else gives up theirs at the same time, forever.

Also, Cherenkov radiation is amazingly pretty for something so deadly. If you see blue beams, get away. Then again, it's probably already too late for you.

Arstechnica has an article up disagreeing with the experiment:

http://arstechnica.com/news.ars/post/20070816-faster-than-the-speed-of-light-no-i-dont-think-so.html (http://arstechnica.com/news.ars/post/20070816-faster-than-the-speed-of-light-no-i-dont-think-so.html)

Sort of the same reason there can't be something that's colder than absolute zero.  The concept of velocity as we currently define it caps out at lightspeed, since we define velocity as distance travelled over time elapsed, and at lightspeed time elapsed ends up hitting zero (from the reference frame of the object in motion).  Much like temperature as we define it, which boils down to a function of the kinetic energy of the particles that make up an object, bottoms at out absolute zero (because at that point the energy of all the particles in the object would be nil, and something can't very well have negative energy).

I'm not saying time travel is necessarily possible (although I wouldn't entirely rule it out).  I'd be more inclined to say that travelling faster than light isn't.

(edit) At least in, you know, space.  If you want to invent a separate universe/dimension/whatever like the Star Trek writers did ("subspace"), and posit that all the physical properties are different there, and that it's possible to pop across the border, drive really fast according to the higher local speed limit, and then pop back, that's a fairly reasonable way to explain FTL travel.

I want to know when some of this fancy science is going to allow me to get an HD signal from a satellite through a fir tree. Daddy needs his NFL Ticket.

If this were that case, then we'd instantaneously see the entire universe. Light moves relatively (sorry, not trying to be punny) slowly. Light years. Thus, rather than deny there could be a faster scale of movement, I'd say our concept of velocity (and time) is a bit off, and if we discover whatever moves on that faster scale, we would then tweak the dependencies accordingly.

Just to throw in a different perspective--special relativity doesn't imply that it is impossible to travel at velocities higher than light in a vacuum--it implies that:

a) you cannot accelerate past c. As your velocity approaches c, more and more of your energy goes directly to mass, and not velocity, and at c all additional energy added to an object is turned directly into mass, no velocity delta.

b) for objects that are already above c in velocity, it implies what Sam mentions (reverse time, basically).

While never observed, tachyons for example are theoretical particles that have a minimum velocity of "just above c", and therefore would travel in reverse time.

Quantum tunneling.

And a chainsaw.

The fir tree cannot take up your entire south side of your house. Can it?

It also cannot be impervious to the cold bitch of a chainsaw.

Nitpick, but it also states you cannot be at c either, exempting massless particles (such as photons).  Anything with a rest mass cannot be at c without infinite energy (read: you can't do it even in theory).  As you approach c, energy/velocity is actually a asymptote on the high end.  Additional energy always correlates to an increase in velocity, but the closer you get to c, the less effect it has.  Sort of like the story of always cutting your distance to a point in half, you'll never actually get there.

As a tie in, it's worth noting that the famous e=mc^2 only makes sense with respect to objects at rest or near rest.  The full equation is a series, with the other bits being effectively irrelevant with low velocity.  At velocities close to c they become increasingly relevant, adding more and more non-trivial terms as the velocity goes up.  Because the series is infinite, at v=c the series becomes infinite, requiring infinite energy.

Well, that makes it easy. We render something massless, and fire that puppy up. :)

It (and the one behind it in the neighbor's yard) take up ~ 40 degrees to the SE, which is where the satellite is. Be nice if they could geosynchronize one over the Pacific along the equator to give another option to their potential customers. Or buy some cell towers and bounce the signal along.

The difference in reference frames is important.  The thing that drives the concept of relativity is the speed of light being the same from all reference frames. 

It's like this: you're in a car going 50mph (relative to the road) and there's a car in front of you going 60mph (relative to the road).  The other car in front of you is going 10 mph relative to you, and you're going 10mph (backwards) relative to it.  But to an observer standing on the road, you're going 50mph and the other car is going 60mph.  This will hold true whether he's seeing you, hearing you, or whether he's got little trip alarms set up on the road, recording when you go whizzing past, and measuring the interval.

Now suppose that the car in front of you is light.  Let's suppose that lightspeed is now only 100mph, since it makes this easier to picture and the actual value of c doesn't matter that much to the concept.  Light is going at 100mph relative to the road.  You're driving along at 50 mph relative to the road.  You might think that light is going 50mph relative to you.  But, in fact, if you measure it you will come up with 100mph.  As will the observer on the road if he measures it from where he is.  Both at the same time.  And again, this has nothing to do with the time it takes for visible light to pass between you and the observer, or whatever; it all holds true regardless of what you use to measure it.  This sounds weird as shit, but it's the only way to satisfy the condition of light having the same speed in all frames of reference.  AND it's been experimentally verified, which is even weirder.

(I think I got that right.  It's been a long-ass time since college physics now.)

Damn, was reading through the thread and links before getting called AFK. But can't not post a response to this:


Chewbacca was from Kashyyyk, enslaved on a Star Destroyer (I think he was some place before that too but am too lazy to look it up). He never lived on Endor.

Of course, Endor was supposed to be Kashyyyk, but they couldn't afford that many 7' costumes. And then they only could for Ep 3 because of CGI (though they did have quite a few costumes).

Depends on what matters more to ya: lore or RL moviemaking constraints :)

It's a South Park reference, D.  Don't feel too bad though, it always bugged the shit out of me too.

In the Christmas special he was living on Endor.  Or at least what's left of my brain seems to recall that.

Also, I'm not sure about Samwise's explanation of relativity because it doesn't account for Doppler effect, red-shift/blue-shift, or at least I don't see how they mesh.

I always get trapped in the straight man role  :-P

Doppler effect isn't based on the velocity of the waves, but the frequency. In red/blue shift effects, all that is changing is the perceived wavelength of the light, not the velocity of the wave propagation (avoiding dual wave/particle nature here, because I don't know how it applies, and the reference article on Relatavistic Doppler Effect (http://en.wikipedia.org/wiki/Relativistic_Doppler_effect) only discusses the wave aspects).

The article specifically states that the wave propagation rate is the constant c.

The Doppler effect on light doesn't work quite like it does with sound.  When you move toward a sound source, the frequency increases because you are moving at a different speed to the waves than you were before.  Instead of being hit with sound at 100mph (to pick our number), you're getting hit at 90.  That differential translates to increase frequency because you're catching up to them more quickly.

That's not what happens with light.  If you were going 99mph (ie, 99% c) you would *still* measure any light source, either infront or behind you, at 100mph.  So would the guy you blow past who is going 0, even if you're measuring the same waves.  You would, however, see dramatic red/blue shifting; everything infront of you would blueshift, likely into gamma, while everything behind you would redshift, likely into long radio.  As a dissapointing side effect, going that large a percent of c would melt your ship due to the gamma radiation, but you could still happily ponder why the light spedometer clocks light at 100 in the process.

Because you play it straight, man.  You need to kick over into the truly crazy to get the laugh.  You know, dance topless, scream gibberish, get a spot on the Muppet show or wrestle women and midgets.