Light so Fast it Travels Backward 415
An anonymous reader writes "Slowing down light used to be considered a neat trick for physics wonks. But researchers in New York now say they've pushed light into reverse. And as if to defy common sense, the backward-moving light travels faster than light." While there's not much use to come of it yet, it will be interesting if Einstein himself is proved wrong.
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Way to read the article, CowboyNeal.
Re:Einstein was proven wrong in his lifetime. (Score:2, Insightful)
my head just exploded (Score:2, Insightful)
Putting on a show... (Score:2, Insightful)
Hard to concieve of. (Score:3, Insightful)
Misconceptions! (Score:3, Insightful)
Re:Negative time was the subject of an Asimov nove (Score:2, Insightful)
However, I believe it would be safe to assume that the prior to sending beam could only appear if you were in fact going to send the beam, as in whatever dimension that allows this to happen, the beam is a single thing moving all at once through space and time, and not travelling unusually at all. It still has to be sent from the one time point to appear at the next. Or previous in this case. I think what I'm saying is the information would have velocity through time only if granted its equivilent of force.
If we were able to receive and then not send, it would be an odd inconsistancy in things.
Re:Two photons travelling in opposite directions (Score:2, Insightful)
This is because of time dilation, which would result in making everything, from the flashlight holder's perspective, appear to be moving really really fast (including the light). A velocity that would normally be measured as 0.001 c will instead be measured as c due to this time dilation.
The stationary observer would, of course, measure the speed of the light as c.
Now, if two flashlight wielders were travelling towards each other in opposite directions, both at 0.99c in their respective directions, I have no idea how to explain what they observe.
Re:Further dossier that Einstein is still the geez (Score:3, Insightful)
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Re:quote (Score:3, Insightful)
This: http://gregegan.customer.netspace.net.au/APPLETS/
LIGHT IS NOT MOVING BACKWARD! Only the "pulse" is.
Look at the simulator and just imagine changing the waves slightly so that the pulse moves backward instead of forward.
The "science" here is not new at all, and the real kicker is this piece of nonsense: "Boyd is already working on ways to see what will happen if he can design a pulse without a leading edge."
He sort of redeems himself by saying: If I do that then it won't work. But just asking the question seems to me that he doesn't understand what's happening here, and is far too excited about something rather simple.
Correction to speed of light issue (Score:2, Insightful)
Seems to me that inside of a speed for light, its just variable speed and we have calculated its speed in a normal situation and labeled it the speed of light.