Physicists at CERN have reported what they believe to be evidence of neutrinos traveling faster than the speed of light. Of course this is usually considered a big “no-no.” So, on the one hand you have people saying that one of the fundamental pillars of physics is close to crumbling (NEWSFLASH!! Call the press!!). On the other hand you have people saying the results are flawed because it’s just too ridiculous to be true (those people at CERN are idiots!).
Frankly, I hate the modern tendency to hype things to opposite extremes. The truth of the matter is that a) the idea has been previously suggested and b) possibly even previously detected in Segré’s and Chamberlain’s famous antiproton experiment that garnered them the 1959 Nobel Prize (as pointed out by Cooper in 1982). In addition, it seems to me that it is becoming clear to a lot of people that both time and gravity are emergent phenomena. Since even special relativity is based on a metric that inherently assumes the existence of time, it would seem that relativity itself is emergent. The “cosmic speed limit” (as Tom Moore calls the speed of light) is taken as one of two postulates from which relativity is derived (the other being that the laws of physics are the same in all inertial reference frames). But that’s all it ever was in the beginning – a good guess. It turned out that causality followed naturally from this assumption and human beings like causality because we can’t imagine how the world would work without it. But maybe causality only applies to macroscopic objects. It seems quite clear that fundamental particles simply do not follow the rules of classical physics (and relativity is a classical theory) so who’s to say they have to be causal? In fact, there are lots of kluge’s in quantum field theory (QFT) that allow for all sorts of bizarre behavior (with all sorts of ad hoc arguments added to assuage our feelings about causality).
So does this all mean we toss relativity out the window entirely (not to mention the Standard Model and most of QFT)? Well, no, not exactly. Look, engineers (and by extension anyone who owns any GPS-based device) rely on relativity every day to make the GPS system work. Likewise quantum electrodynamics (QED), which is inherently relativistic, is the single most accurate scientific theory known (it agrees with experiment to some insane number of decimal places). So what it means is that we are merely pinning down the limitations on the theory. All theories are really nothing more than models – they’re simply the most self-consistent way we have to describe the reality we see until we find something better. For example, the discovery of relativity didn’t stop people from using Newtonian mechanics – again, engineers use it every day to make sure buildings stand up and cars drive properly.
So, in short, don’t believe the hype – either way. It’s not the end of physics as we know it. But it is wicked cool and very exciting because it means we’ve just discovered another “layer of the onion” we call the universe.