Among those who study the human mind and consciousness, there is what is termed “The Hard Problem.” It is in contrast to, and qualitatively different from, problems that are merely hard. (Simply put, The Hard Problem is the question of how subjective experience arises from the physical mechanism of the brain.)
This post isn’t about that at all. It’s not even about the human mind (or about politics). This post is about good old fundamental physics. That is to say, basic reality. Some time ago, a friend asked me what was missing from our picture of physics. This is, in part, my answer.
There is quite a bit, as it turns out, and it’s something I like to remind myself of from time to time, so I made a list.
I’ve posted more than once regarding my view of the Many Worlds Interpretation (MWI) of quantum physics. I find its rise in modern popularity genuinely inexplicable. (I can’t help but think it’s exactly the sort of thing Dr. Sabine Hossenfelder is talking about in her book, Lost in Math.)
Hoping to find the logic that apparently appeals to so many, I read Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime (2019), by Sean Carroll. It is, in large part, his argument favoring the MWI. Carroll is a leading voice in promoting the view, so I figured his book would address my concerns.
But as far as I can tell, “there is no there there.”
I’ve come to realize that, when it comes to the Many Worlds Interpretation (MWI) of quantum physics, there is at least one aspect of it that’s poorly understood. Since it’s an aspect that even proponents of MWI recognize as an issue, I thought I’d take a stab at explaining it. (If nothing else, I’ll have a long reply I can link to in the future.)
The issue in question involves what MWI does to probability. Essentially, our view of rare events — improbable events — is that they happen rarely, as we’d expect. Flip a fair coin 100 times; we expect to get heads roughly 50% of the time.
But under MWI, someone always gets 100 heads in a row.
I finally finished Our Mathematical Universe (2014) by Max Tegmark. It took me a while — only two days left on the 21-day library loan. I often had to put it down to clear my mind and give my neck a rest. (The book invoked a lot of head-shaking. It gave me a very bad case of the Yeah, buts.)
I debated whether to post this for Sci-Fi Saturday or for more metaphysical Sabbath Sunday. I tend to think either would be appropriate to the subject matter. Given how many science fiction references Tegmark makes in the book, I’m going with Saturday.
The hard part is going to be keeping this post a reasonable length.
I was surprised to discover I’ve never posted about the Many Worlds Interpretation (MWI) of quantum physics — I would have sworn I had. I’ve mentioned it a few times, and I know I’ve discussed it in comment sections, but it seems I never tackled the subject explicitly for the record.
It’s been on my mind lately because others have talked about it. Sean Carroll’s book promoting it generated a wave of discussion. The final push for me was Jim Baggott’s Farewell to Reality, which consigns MWI to the “fairy tale physics” heap.
Since I quite agree, this seems a good followup to yesterday’s post.
My voracious reading habit has deep roots in libraries. The love of reading comes from my parents, but libraries provided a vast smörgåsbord to browse and consume. Each week I’d check out as many books as I could carry. I discovered science fiction in a library (the Lucky Starr series, with Isaac Asimov writing as Paul French, is the first I remember).
Modern adult life, I got out of the habit of libraries (and into book stores and now online books). But now the Cloud Library has reinvigorated my love of all those free books, especially the ones I missed along the way.
For instance, Farewell to Reality: How Modern Physics Has Betrayed the Search for Scientific Truth (2014), by Jim Baggott.