Our back-end team sometimes adds calls to a new service that they're building to test the load, a lot like this! So the idea was in the air at OkCupid, so to speak. And with such a big new piece of infrastructure, I knew there would be problems, it's just how it works. So I wanted to get something into production really quickly to have something to troubleshoot against.
Me too. I grew up in Germany and on one of our trips to the US (late 70s maybe) we discovered Mad Magazine. My dad decided we all needed a subscription - he was always trying to find ways for the kids to brush up on their English. So for many years we had Mad Magazine mailed to us in Germany. We tried not to mess up the page for the other readers in the family.
Author here. Thanks for educating me on the subtleties. It seems like I was mixing up a Level 3 multiverse with a Level 2. I made a small edit to remove the sentence about constants changing. And I also added a note that I edited the post.
MWI is just one of multiple multiverse ideas. Most multiverse ideas (like Tegmark's Levels I, II, and IV) are basically what-if ideas without any direct evidence, but MWI specifically happens to be a more-grounded idea based on trying to make sense of what the (well-tested) Schrodinger equation says about reality.
The first part of your description of MWI ("The many-worlds interpretation of quantum mechanics imagines our universe as one node in an infinitely branching tree of universes where every possible quantum outcome exists in its own universe.") is pretty good, if a slight though common simplification (different branches aren't entirely separate, so envisioning it as a tree is only mostly correct; different branches can sum together or cancel each other out if their configurations are identical).
> trying to make sense of what the (well-tested) Schrodinger equation says about reality.
Nitpick: The Schrödinger equation predicts unitary time evolution (which is another way of saying that physical systems evolve in a deterministic manner). Interpretations of quantum mechanics exist to make sense of the part of quantum mechanics that doesn't follow unitary time evolution, namely the measurement process.
if you read "Our Mathematical Universe: My Quest for the Ultimate Nature of Reality" by Max Tegmark, many worlds falls in the bucket of L3 multiverse. What you're describing is a L4 multiverse (see comments below. seems it's L2, not L4. will leave my mistake in, although i'm sure there is a parallel universe where i did not make this mistake)
Level 2 is universes generally like ours but with different physical constants: https://en.wikipedia.org/wiki/Multiverse#Level_II:_Universes.... Level 4 includes all abstract mathematical structures, like a universe embedded in a Game of Life simulation.
I'm not sure which Sean Carroll talk you saw, but I think he only mentions the differences between worlds in terms of different "choices"-- and these universal constants don't "choose" to be what they are, right?
I like the table of contents at the beginning with the links. I'm going to steal that for my next blog post. The author is a really clear writer, and I love the table of contents because you can jump around and things are bite-sized.
