First, new scientist reported on an experiment that really very strongly suggests that in some cases it is possible for photons to travel faster than the speed of light. Completely aside from the apparent oxymoron of saying that light traveled faster than itself, (being as “photon” is a word that means “unit of light”) this is the first directly observed violation of relativity that has ever been documented. To really appreciate how big this is you have to understand that the speed of light is, according to relativity–the most accurate model of the large scale universe ever devised–, the absolute upper bound for the maximum speed of anything, ever. Nothing goes faster than than the speed of light, the speed of light is what everything is relative to!
I hope that my redundancy conveys my excitement in the absence of my wildly flailing arms.
OK, the second thing to be reported, this one on one of the blogs of one of the editors of scientific american, is that some observers at a gamma ray telescope noticed that light at two very different energy levels (approximately an order of magnitude apart at the TeV range) coming from a distant supernova arrived with an approximately 4 minute separation. That is to say, assuming they didn’t overlook something, light that started at the same place and time arrived here at different times. As i mentioned in the previous paragraph, light is the thing which everything else is relative to, it’s what gives relativity its name. Not only is the speed of light in a vacuum (almost 300million m/s) supposed to be the absolute maximum speed for everything in the universe, all light is supposed to travel at exactly that speed. It seems very likely that quantum mechanical effects affected the light. And, what’s more, if you look at the end of the SciAm article you’ll see that the energy difference of the photons correlates to the energy of a string. Or something. Frankly i don’t quite understand that part.
So what’s the big deal? you might be asking. Isn’t this what science does? Well, yes. We basically knew that something like this was coming: the massive inconsistencies between General Relativity and Quantum Mechanics means that something’s got to give. Somewhere, somehow, somethings got to be wrong. But this is the first time that we’ve seen it. To give you a metaphor that compares science to parties: Remember that time that you went to that party that the girl you really like and hope to finally make some headway with is supposed to be at. Because every time you’ve seen her she’s been on the other escalator or something, but all your friends say you two would get along great and share interests in those obscure things that nobody cares about. But now you see the door open and there’s a silhouette and…
Well, that’s where this discovery puts us. We’ve now got a silhouette.
If these observations stand the weight of scientific scrutiny then we are seeing the first empirical evidence prodding us to go beyond relativity. The last time something this big happened in science was the famous experiment when astronomers saw the sun bend the light of a star in its gravity well.
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Sorry to burst your bubble, but the experiment reported in the New Scientist does not violate special relativity. It’s been known for more than 20 years now that the group velocity of a wave can be faster than its phase velocity. (Incidentally, the converse can also happen.) But in none of these experiments is the signal velocity more than c, so special relativity remains unviolated. A good explanation of the distinctions between group velocity, phase velocity and signal velocity can be found here:
http://tinyurl.com/2snb6r
OK, reading that article you link to gives me a (slightly) better idea of what the train analogy was like at the end of the NS article, but i’m not sure that it’s 100% applicable. It seems like the Scientists who did the photon tunneling experiment managed to increase the distance travelled by every part of the wave by merely diverting it through a prism and convincing it to act more quantum mechanically than relativistically.
It Does seem like there was a trade-off though, significant signal-quality reduction for the increase in speed. Great enough that they couldn’t get more than a meter of ’superluminal’ transit before they lost everything. And, frankly, the article doesn’t mention the really important thing: if the guys thought that they would be able to transfer information in this manner. If they suggested that their next experiment would aim to get information traveling ftl, even just morse code, well then: hey.
But they didn’t, and now i know that the article didn’t even give me enough information to be able to determine if they even have evidence for having done what they claim to have done.
But what about that other one, huh? That’s a big deal.
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