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0 pointslmm5y ago0 comments

> I don't understand how purely unitary evolution can explain this. Does it?

What's the alternative? Assuming unitary evolution and some fairly common-sense axioms about how we'd expect subjective experience to behave (things like: we never experience being in a branch that has amplitude zero; if we experience being in a given branch then we continue to be in that branch), the Born probabilities are the only model anyone's ever come up with for how our subjective experience should go. So what's there to explain?

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millstone5y ago

The alternative is non-MWI theories, which typically introduce the Born rule via new axioms.

Regarding what's to explain, it's quantum randomness (which distills the Born rule objection). Our subjective experience is that we see spin-down 1/3rd of the time, and our theories say the result is otherwise impossible to predict, even in principle. But a deterministic theory cannot produce a random outcome, even a subjective one.

lmmOP5y ago

> Our subjective experience is that we see spin-down 1/3rd of the time, and our theories say the result is otherwise impossible to predict, even in principle. But a deterministic theory cannot produce a random outcome, even a subjective one.

Whyever not? What else would you expect the subjective experience of being in a state like 1/sqrt(3)|x> + 2/sqrt(3)|y> to be like?

Orlanthai5y ago

There's a continuous infinity of alternate basis expansions. There's no reason to think you'd experience along that particular basis.

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Orlanthai5y ago

Derivations like that don't work, you've just declared it by fiat but there's no such proof that is known to work.

lmmOP5y ago

There's no proof that it's the only possible way - but no-one's ever been able to come up with a concrete alternative.

Orlanthai5y ago

There are other alternatives such as the derivation of quantum theory within the GPT framework and many other axiomatic derivations.

I've never seen the Born rule derived from unitary evolution and axioms for how subjective experience should work, so I don't even see this as one of the ways.

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0 pointslmm5y ago0 comments

> I don't understand how purely unitary evolution can explain this. Does it?

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millstone5y ago

The alternative is non-MWI theories, which typically introduce the Born rule via new axioms.

lmmOP5y ago

Whyever not? What else would you expect the subjective experience of being in a state like 1/sqrt(3)|x> + 2/sqrt(3)|y> to be like?

Orlanthai5y ago

There's a continuous infinity of alternate basis expansions. There's no reason to think you'd experience along that particular basis.

1 more reply

Orlanthai5y ago

Derivations like that don't work, you've just declared it by fiat but there's no such proof that is known to work.

lmmOP5y ago

There's no proof that it's the only possible way - but no-one's ever been able to come up with a concrete alternative.

Orlanthai5y ago

There are other alternatives such as the derivation of quantum theory within the GPT framework and many other axiomatic derivations.

I've never seen the Born rule derived from unitary evolution and axioms for how subjective experience should work, so I don't even see this as one of the ways.

j / k navigate · click thread line to collapse