Faster than light ...

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Permalink Reply by Sean Murphy on September 22, 2011 at 6:01pm

Not as much as you might think, although it would conflict with any studies that found neutrinos have positive mass. You see, it is an oversimplification to say that General Relativity says nothing can travel faster than light. Anything with a positive Absolute Mass will need infinite energy to speed up to the speed of light. Anything with a negative mass will need infinite energy to slow down to the speed of light. I've seen speculative articles before suggesting that neutrinos could be faster-than-light particles, or Tachyons as Theoretical Physics and Science Fiction have named them.

Permalink Reply by Steven Patterson on September 22, 2011 at 8:22pm

While special relativity does seek to constrain things with mass from moving faster than the speed of light (with respect to each other), there is no such constraint in general relativity. Many real life examples of this exist, for instance, our expanding universe (or conversely, a black hole) has an event horizon, which marks the boundary to that part of the universe an observer cannot see. Objects beyond this boundary are moving away from the observer faster than the speed of light, and are therefore invisible for that reason. Also, remember that in the early nano-seconds of the Big Bang, every bit of the universe was expanding at many times the speed of light. The prohibition against FTL is a myth. We may never do it ourselves, but it can be done. The Universe is doing it as we speak . . . er, blog.

Permalink Reply by annet on September 23, 2011 at 7:34pm

This is a great announcement and challenge put out by Cern. It is nice to see so many people, even those not normally interested, getting excited about science. 

 

The track record of OPERA-like experiments has many scientists doubting that the result will hold up to further scrutiny. As Martin Robbins at the Guardian points out, one theoritical physicist has promised to eat his boxer shorts on live TV if the results turn out to be true.

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