I had an incredibly frustrating conversation this morning trying to explain the idea of quantum immortality to someone whose understanding of MWI begins and ends at pop sci fi movies. I think I've identified the main issue that I wasn't covering in enough depth (continuity of identity between near-identical realities) but I was wondering whether anyone has ever faced this problem before, and whether anyone has (or knows where to find) a canned 5 minute explanation of it.
"Very improbable" is the typical assumption with MWI, but I think that it is mistaken in most cases dealing with complex systems.
Each wave-function sets limits on what can occur. Wave-functions don't have infinite extents, there are areas with zero amplitude. Each additional wave-function that must meet specific requirements further restricts the possible outcomes. In general, the likelihood of failing to meet the simultaneous condition grows exponentially as the system size grows linearly.
Since quantum survival (avoiding death in some worlds, in some meaningful context) will usually require a very large number of quantum level alternatives to be simultaneously selected for, quantum survival will almost always be impossible.
A person who experiences quantum survival once is very lucky, but almost certainly won't survive the next time. A person who fails to experience quantum survival never gets another chance.
So my conclusion is that quantum immortality is impossible, not just very improbable.
Your logic here makes no rational sense. Your saying things which can be proved to be false.
Firstly I accept your premise that some things have zero probability. The wave-function doesn't mean literally anything can happen
BUT
I strongly disagree with you when you start saying that simultaneously selecting for possible (but improbable things) makes them impossible because this makes no rational sense. Quantum events are independent of each other the fact that 1 radioactive atom decays doesn't mean that the next is more or less likely to (unless they int... (read more)