All That Matters

The young Max Planck, when completing his high school degree, asked a professor of physics at the University of Munich, Philipp von Jolly, whether he should study physics. He got the famous answer that this wouldn’t make much sense, because physics is an almost fully mature science with not much to discover. (If you happen to speak German, it is worth reading the original text, reprinted in this biography of Max Planck.)

Of course, luckily Planck ignored this advice and went on to make some of the most profound discoveries in modern physics. And well, if you think we are in a similarly dull situation in physics at present, the past few weeks would have certainly disproved this, because a couple of intriguing, unpublished (in the academic sense) research findings have appeared widely in the news: neutrinos that continue to appear to be faster than the speed of light, a completely new view on wavefunctions in quantum mechanics, and it seems also that there isn’t much hiding space left for the Higgs boson, if it exists.

Arthur Eddington's 1919 photograph of the sun during a total eclipse. The position of the stars appearing behind the sun verified Einstein's theory of relativity. Photo via Wikimedia.

Those discoveries all come with the promise of significant changes to our understanding of physics, and we’ve seen some exposure in the news (and the occasional hype, too). This is perhaps not surprising. The neutrino experiment questions the theory of relativity. The absence of the Higgs boson on the other hand would open the question again about the different masses of particles. And the new view of wavefunctions seems to add further to the arguments whether the wavefunctions in quantum mechanics are purely an expression of probability to find an object in a certain physical state, or are a representation of actual reality. The paper now rules out the possibility that wavefunctions are probabilistic states, but still having an underlying reality. Instead, there are two interpretations left. One can either fall back to the argument that there is no underlying reality in quantum mechanics and wavefunctions simply are nothing but probabilistic. Or, the second option is that wavefunctions are an expression of actual reality, abandoning the probabilistic interpretation. Not surprisingly, for this reason the paper got lots of headlines. Most people my colleagues at Nature spoke to were quite enthusiastic, whereas Scott Aaronson didn’t seem to see that much of a surprise. Matt Leifer has an informative, quite detailed description of the paper on his blog. […]