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挑战爱因斯坦的不只有民科

已有 2752 次阅读 2016-4-28 17:36 |个人分类:科学感想|系统分类:科普集锦

我们知道，民科最想挑战爱因斯坦，要么声称爱因斯坦的相对论错了，要么声称找到有比光速还快的东西。

其实，官科也想挑战，但他们的理由是否一致，咱外行，不清楚。

下面是官科的理由：

So far, Einstein still comes out on top, and the theory holds. But the researchers hope to follow up the experiment with a more precise trial that might prove capable of poking holes in special relativity. That could actually be a good thing, scientists say, at least in terms of the advancement of physics. [10 Implications of Faster-Than-Light Travel]

“As a physicist, I want to know how the world works, and right now our best models of how the world works — the Standard Model of particle physics and Einstein’s theory of general relativity — don’t fit together at high energies,” physicist Michael Hohensee of the University of California, Berkeley, said in a statement. “By finding points of breakage in the models, we can start to improve these theories.”

见：Speed Of Light Experiment Confirms Einstein Theory

为什么光速如此重要呢？为什么光速是宇宙速度的极限呢？

Under Einstein's theory, the speed of light becomes a sort of ultimate speed limit. In fact, objects with mass, be they cars or neutrinos, can't reach the speed of light because they would need infinite energy to do so, according to the theory.

Some experiments have appeared to play with the speed of light, but these effects are illusory, according to Galison. Light traveling through different mediums, such as chilled sodium gas, does slow substantially, but this is because the light is being bounced between the atoms within the medium. But between interactions with atoms, it is still traveling at 186,000 miles per second (300 million meters per second), he said.

Claims that it's possible to push light beyond 186,000 miles per second (300 million meters per second), are equally illusory, Galison said.

Galison uses a hypothetical to explain why. If you shine a laser pointer on the surface of the moon and flick your wrist to sweep across the surface, wouldn't that mean that the bright dot is crossing the surface of the moon faster than the speed of light? No, because nothing is actually crossing the surface of the moon — the dot isn't an actual object, it is just a series of photons in the laser beam hitting the surface.

"For 100 years, people have used these and more sophisticated paradoxes to try to say, 'Well isn't there this way to exceed the speed of light?'" Galison said. "They usually turn out to involve accelerating motion, something that is not really an object" — like the bright spot of the laser pointer — "or infinite energy." In other words, cheats.

In the lab, researchers can create the impression of sending light faster than the speed limit by tweaking the speed at which the wave crests of light propagate through space. This, however, does not increase the speed at which the actual electromagnetic information travels — this is conveyed by the overall shape of the wave's amplitude.

见：Why The Speed of Light Matters | Theory of Special...