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dbvdh | on: I don't understand quantum physics (2018)
Does it not make any predictions? It states there is no such thing as wavefunction collapse. This means that if you entangle a state with a large system, in theory you could ‘disentangle’ it. Of course, this is no easy feat. But indeed quantum computing to me, is an example of this feat. We can entangle systems on a large scale, then use this feat to make calculations. Inspiration for quantum computing actually came from many worlds.

Many worlds is falsifiable, if you can show wave function collapse actually happens (not just decoherence). I believe that in the not so distant future we will get more and more proof that wave function collapse never happens. Quantum computing at scale to me is an indication that Everett was just right..

unparagoned | parent | next
Nope it’s the opposite. The Copenhagen wavefunction collapse is untestable or unfalsifiable.

With many words, every postulate has been tested and very verified. What more can you ask from a theory?

Now objective collapse is a testable postulate but none expects that to pan out.

EvgeniyZh | parent
> This means that if you entangle a state with a large system, in theory you could ‘disentangle’ it.

This can be done in any other interpretation? Any unitary evolution on an isolated system can be reversed. This is a mathematical statement.

> Many worlds is falsifiable, if you can show wave function collapse actually happens

So, what experiments do you think would falsify it? How can you show that collapse actually happened?

dbvdh | root | parent
In the Copenhagen interpretation, when I look at schrodingers cat, the wavefunction will collapse. After I have looked at it, no way to go back. Information is lost. In many worlds, I just become entangled with the system - and I could theoretically disentangle after. Like quantum computing going to a deterministic outcome in a certain basis.

Showing collapse happened is really tricky because of decoherence. Similar to unmixing coffee and milk. But all systems we have observed so far do not show wave function collapse (granted these systems are generally small, but otherwise decoherence starts messing about).

These are just fundamentally different theories. Not just an interpretation, physically different outcomes.