What’s the observation you’re going to make that has probability near-1 on MWI and probabilty near-0 on collapse—and probability given what?
“I’m alive at 120, here and now”—that has small probability either way. (On most branches of the wavefunction that include your present self, no version of you gets to say that. Ignoring, as usual, irrelevant details involving positive singularities, very large universes, etc.)
“90 years from now I’ll still be alive” (supposing arguendo that you’re 30 now) -- that has small probability either way.
“I’m alive at 120, conditional on my still being alive at 120”—that obviously has probability 1 either way.
“On some branch of the wavefunction I’m still alive at 120”—sure, that’s true on MWI and (more or less by definition) false on a collapse interpretation; but it’s not something you can observe. It corresponds exactly to “With nonzero probability I’m still alive at 120″, which is true on collapse.
“90 years from now I’ll still be alive” (supposing arguendo that you’re 30 now) -- that has small probability either way.
This is the closest one. However, that’s not an observation, it’s a prediction. The observation is “90 years ago, I was 30.” That’s an observation that almost certainly won’t be made in a collapse-based world; but will be made somewhere in an MWI world.
“I’m alive at 120, here and now”—that has small probability either way. (On most branches of the wavefunction that include your present self, no version of you gets to say that.)
“small probability either way” only applies if I want to locate myself precisely, within a branch as well as within a possible world. If I only care about locating myself in one possible world or the other, the observation has a large probability in MWI.
What’s the observation you’re going to make that has probability near-1 on MWI and probabilty near-0 on collapse—and probability given what?
“I’m alive at 120, here and now”—that has small probability either way. (On most branches of the wavefunction that include your present self, no version of you gets to say that. Ignoring, as usual, irrelevant details involving positive singularities, very large universes, etc.)
“90 years from now I’ll still be alive” (supposing arguendo that you’re 30 now) -- that has small probability either way.
“I’m alive at 120, conditional on my still being alive at 120”—that obviously has probability 1 either way.
“On some branch of the wavefunction I’m still alive at 120”—sure, that’s true on MWI and (more or less by definition) false on a collapse interpretation; but it’s not something you can observe. It corresponds exactly to “With nonzero probability I’m still alive at 120″, which is true on collapse.
This is the closest one. However, that’s not an observation, it’s a prediction. The observation is “90 years ago, I was 30.” That’s an observation that almost certainly won’t be made in a collapse-based world; but will be made somewhere in an MWI world.
“small probability either way” only applies if I want to locate myself precisely, within a branch as well as within a possible world. If I only care about locating myself in one possible world or the other, the observation has a large probability in MWI.