Faster than a speeding photon...

[California Tanker]

Error - Prolexic (http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/08/16/scispeed116.xml)

Boxhead boffins claim to have broken the light barrier.

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.

Read on...

NTM

[Crumb]

For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.
I don't understand how that follows... :confused:

[California Tanker]

Theory of relativity. The closer you get to light speed, the slower time goes for you in comparison to the stationary universe. At light speed, time is instant.

I presume they're just taking it to its logical conclusion. If, indeed, time is a dimension, I don't see why it's impossible. I just can't get my head around it, but I'm sure it's mathematically feasible, just like negative numbers.

NTM

[But]

Here is the paper:

403 Forbidden (http://arxiv.org/abs/0708.0681)

Hmm, don't know why the automagical url thing chose that title, but I'll leave it because it's funny.

[Dragar]

They haven't really. Quantum tunneling is a well known phenomenon, which makes it appear that you have moved something faster than the speed of light. You have to be careful about what you mean by something's velocity.

For instance, If I shine a laser-pointer on the moon, it will make a spot (okay, pretend it's a good enough laser that it retains coherence and isn't absorbed by the atmosphere. And we've a good telescope to watch). A flick of my wrist can send that dot to the other side of the moon, and it won't take much to make that spot travel faster than the speed of light.

Does this violate special relativity? No, although it can be tempting to think so. But that 'dot' on the moon is not a real thing; it carries no energy nor information. So it's quite alright for it to move faster than c.

These tunelling experiments are much the same thing. If you're interested, check out this site (http://www.aei.mpg.de/~mpoessel/Physik/FTL/tunnelingftl.html).

Even if you don't buy that argument, I know this can't have violated causality, because the theory they have verified with these experiments (QED) is built around special relatvity and quantum mechanics combined. And theories that make predictions that contradict their assumptions are not popular in physics. :yup:

[Kyuss Apollo]

Ooooh, tachyons!

[viscousmemories]

Dragar! Good to see you. :)

I read about this last night at Engadget (http://www.engadget.com/2007/08/16/german-scientists-claim-to-have-broken-speed-of-light/), where they also posted a link to this skeptical article (http://arstechnica.com/news.ars/post/20070816-faster-than-the-speed-of-light-no-i-dont-think-so.html).

[Crumb]

Ah, time dilation. :duh:

Thanks for the explanation, Dragar.