When I first started studying physics seriously, Einsteinian relativity really bugged me. It just didn’t make sense. So I worked really hard to understand it—harder than I ever worked to understand any other kind of physics. And I never had an epiphany. Instead, I just accepted it. Relativity was just the way the world was. Things that are moving very fast relative to each other simply behave in ways that my intuition based upon things moving slowly did not prepare me to understand. Dr. Einstein or: how I learned to stop worrying and love relativity.
By the time I got to quantum mechanics, I was a Zen Master. It bothers you that reality is just a cosmic poll of individual quantum occurrences? The cow is slow but the earth is patient, Grasshopper! Or more to the point: shut up and solve your equations! And as time went on, I took some amount of solace in the belief that theories were not reality. One thing they don’t tell you in school: the very best theories might be accurate to within one part in a million. But no theory is perfect. And that makes reality a whole lot more interesting.
It also makes our place in the cosmos a lot more tenuous. As physicists bombarded atoms with more and more energy, I came to believe that we were likely just banging our metaphorical head against the box of reality that we were caught in. After all, with paradoxes in pure math, how could our physical reality be any less bizarre? At first, this led me to think that quantum mechanics must just be an outcome of our limited perception of a greater reality.
It turns out that the great physicist Hugh Everett thought much the same thing—although he did with equations because he was all smart and shit. But before getting to what he had to say, let me just say that Everett was my kind of a physicist. He over-ate, over-drank, and over-smoked. And he paid the price, dying at 51 back in 1982. He was a man of many vices and I respect that! Anyway, he claimed in a one-dimensional universe where a particle can go one way or the other, it goes both. Basically: there are two universes. And so on…
Now don’t start with me! I know the objections. It sounds like madness. It implies an ever increasing number of universes. Well, get over it! The truth is that when you get to cosmology, nothing really makes sense. Sure, the Big Bang makes sense. But as a cosmological theory, it is every bit as unhelpful as the God theory. The nature of reality has to be really strange—so strange that it doesn’t make any sense to us.
And that is why I wrote above that “at first” I thought that quantum mechanics was just our view of a larger reality. There is a problem. It implies that if we could see all of reality, it would make sense. But it wouldn’t. It would be just like relativity. We are by our nature parochial. The only stuff that makes sense is what we know from our parochial reality. But it is nice to imagine another parochial reality where all the quantum statistics broke his way, and Hugh Everett is a grand old man enjoying his retirement in Virginia.
H/T: Brad Plumer