String theory and the multiverse...the answer to Existence.

[Soleron]

WereKitten said:

Soleron said:

...

Parallel universes are one valid interpretation of QM, yes. But as we cannot travel to them it's not worth thinking about them.
...

In Everett's original work on relative states in QM there's nothing like the "bifurcation of world stories" as often popularized. The so called many worlds interpretation (MWI) in his original proposal is actually "just" a numerically frightening decoherence of the superposed eigenstates when entangled with macroscopic observers.

As such -at least in principle- Everett's interpretation of QM can be testable: if we ever managed to create a small, insulated, simple process of quantum measurement that we can fully reverse, then we should observe "decollapsing" of the wave packets. Or in MWI-speak: we should be able to see the "alternative worlds" originated from that single measurement interfere again in a controlled way. How that would work in practice e.g. how do you keep track of the results is not clear to me :)

To the OP: google for Tegmark's multiverse and look at his type IV multiverse idea if you want an even wilder ride :)

Of course. I just didn't want to go into eigenfunction stuff. Real scientific 'teleportation' and 'time travel' and 'wormholes' also function nothing like the popular science version.

Wouldn't that test give the same answers under Copenhagen?