I was chatting with some friends (online) today about the announcement of the Nobel Prize for Physics. They wanted a simple explanation of the work that the prize was awarded for, so I came up with something by paraphrasing some slightly more complex explanations I found.
(A) Realism is the concept that things have definite states, even if nothing interacts with that state. (i.e. the hidden variable interpretation of quantum mechanics – an electron has a spin, even if you haven’t measured it yet.)
(B) Locality is the idea that only nearby things affect you. For distant things to affect you, they need to send something near to you: photons, gravity waves, etc.
What the Nobel laureates proved is that A and B are not both true. (But we don’t know which. A could be false, or B could be false, or both could be false.)
If A is false, then essentially it means the Copenhagen interpretation is true – quantum objects don’t have states until they are observed. If B is false, then it means that quantum entangled particles affect each other even when widely separated, without sending any sort of message between them. We (i.e. quantum physicists) have strongly suspected this for decades, but the Nobel dudes proved it. The first work on this result was way back in 1972, but the final experiment that tidied up the loose ends and cemented it was done in 2015. (I’ll also point out that I haven’t actually studied quantum physics for over 20 years, so I’m possibly missing some details with this simplified explanation.)
I’m strongly reminded that fundamentally we have no idea why the universe behaves like it does. All we can do is make models of what we observe to happen. And some of what we observe is incredibly counter-intuitive and ludicrous.
The main news today here though is the weather. It’s pouring down outside as I type this, and we’re looking at a forecast of 100 mm of rain or more overnight, with heavy seas and winds up to 90 km/h. Most of this weather has come in over western parts of New South Wales, where it’s already causing major flooding issues. It came in mid-afternoon, after a morning that was actually fine and sunny allowing me to get a 2.5k run in.
New content today:
The funny thing (to me) is that intuitively, I *know* that locality is valid, and therefore realism is violated. I’m not saying I’m right, I’m saying that my particular brain is just wired not to accept nonlocality.
Curiously, Carl, I’m more willing to believe the opposite. I’m far more able to wrap my head around a universe where “supernatural” communication is possible than one where everything I am not directly observing is somehow ambiguously undefined.
Funny how the brain works, making sense of its inputs. This may be the quantum physics version of a Rorschach test…