On Fri, Feb 14, 2025 at 12:13 AM Brent Meeker <[email protected]> wrote:
> > *>> Schrodinger's equation produces a complex-valued wave that evolves in >> time, the square of the absolute value of the amplitude of that wave >> determines probabilities. You just take the Born Rule as a given because >> experimenters tell you that it works. Many Worlds can tell you why it works >> and why you need it.* > > > *> So you say. But all attempts to derive it, assuming MWI, have failed.* > *I admit there is some controversy concerning the validity of the derivations of the Born Rule that Many Worlds advocates have come up with, but they are the only ones that have even tried. Copenhagen, Objective Collapse, the Bayesian Interpretation and of course Shut Up And Calculate haven't even tried to derive it from their respective interpretations, they just accept the Born Rule as a starting assumption. * *Deutsch and Wallace have proven that if the Many Worlds idea is correct then a rational agent in a branching universe would bet according to the probabilities the Born Rule produces; the only assumptions they needed is that similar quantum states should have similar probabilities, and probability assignments should be stable over time. But some complain that they have not defined "rationality" with enough mathematical rigor. * *And in 2014 Sean Carroll and Charles Sebens used Many Worlds to find another derivation of the Born Rule based on self‐locating uncertainty. However some complain that if you know the full wave function then you should not have any uncertainty at all; I believe that complaint is invalid resulting from confusion over the personal pronoun "you". Another complaint is that they are assuming something called the "Epistemic Separability Principle", the idea that an observer’s credences about local measurements shouldn’t be affected by distant changes in the environment; I can't comment further about that because I don't know what the hell it means.* * >> Many Worlds says everything always obeys Schrodinger's equation >> including the observer, therefore there will always be self-location >> uncertainty, it can't be avoided.* > > *< And how does that result in uncertainty, when you are located in every > branch. * > *Brent Meeker is in every branch but Mr.You is in only one branch, and until Mr.You opens the box and looks at the cat Mr.You lacks sufficient information to know which branch Mr.You is in. If personal pronouns had never been invented the Many Worlds idea would have been universally accepted by the physics community 50 years ago. * *John K Clark See what's on my new list at Extropolis <https://groups.google.com/g/extropolis>* 3ed -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAJPayv0zzamGrmjHt1aK0cDNAiZtLHmZuotT_hxZGj6c%3DYSK%3DA%40mail.gmail.com.
