On Fri, Sep 13, 2024 at 6:45 PM Stathis Papaioannou <[email protected]> wrote:
> On Fri, Sep 13, 2024 at 18:15 Quentin Anciaux <[email protected]> wrote: > >> Le ven. 13 sept. 2024, 10:12, Stathis Papaioannou <[email protected]> a >> écrit : >> >>> On Fri, 13 Sept 2024 at 17:30, Bruce Kellett <[email protected]> >>> wrote: >>> >>>> On Fri, Sep 13, 2024 at 5:23 PM Stathis Papaioannou <[email protected]> >>>> wrote: >>>> >>>>> On Fri, 13 Sept 2024 at 15:08, Bruce Kellett <[email protected]> >>>>> wrote: >>>>> >>>>>> On Fri, Sep 13, 2024 at 1:07 PM Liz R <[email protected]> wrote: >>>>>>>> >>>>>>>> I don't think that works. The idea often put forward is something >>>>>>>> along the lines of self-locating uncertainty -- out of all the >>>>>>>> branches, >>>>>>>> which one am I on? But that is only apparent randomness, and to get >>>>>>>> such an >>>>>>>> idea to work, you need to be able to make a random choice between >>>>>>>> branches. >>>>>>>> Such randomness will be intrinsic in that It doesn't come from anywhere >>>>>>>> else (it is not already part of the theory). So in order to generate >>>>>>>> such >>>>>>>> apparent randomness you actually need an independent source of >>>>>>>> intrinsic >>>>>>>> randomness (to be able to make your self-locating choice.) >>>>>>>> >>>>>>> >>>>>>> The intrinsic randomness arises from the fact that it is impossible >>>>>>> to predict which branch you will end up in, even for an omniscient >>>>>>> being. >>>>>>> >>>>>> >>>>>> That is just a restatement of the traditional measurement problem. >>>>>> Self-locating uncertainty is not intrinsic randomness. What is it that >>>>>> selects which branch you are actually on? You need some means of random >>>>>> selection which is not included in the underlying theory. You have to >>>>>> add, >>>>>> by hand, some additional principle of randomness, such as the Born Rule. >>>>>> >>>>> >>>>> Nothing selects which branch you will be on, since with certainty a >>>>> version of you will end up in each branch. If the omniscient being >>>>> predicts >>>>> that you will end up in branch A, the prediction is wrong for the version >>>>> of you in branch B, and if the omniscient being predicts that you will end >>>>> up in branch B the prediction is wrong for the version of you in branch A. >>>>> It is logically impossible to make an accurate prediction. >>>>> >>>> >>>> It is unfortunate, therefore, that all real experiments result in just >>>> one answer, which is the nub of the measurement problem. Which answer is >>>> unpredictable, but that does not mean that there can be some omniscient >>>> being that can predict your result. It is a matter of an intrinsic >>>> probability -- *viz*. the Born Rule. >>>> >>> >>> The branching makes the outcome fundamentally unpredictable, which is >>> what randomness is. It results from the branching and nothing else. It is >>> not specific to QM or MWI: it results from any process where the observer >>> branches. >>> >> >> The thing is to recover the born rules, some frequency must be in play, >> some things are more likely than other, if you had to make a bet, it's >> important and you wouldn't bet every outcome is equally likely. >> > > Isn’t that separate from the question of whether the randomness an > observer sees in MWI is truly random? > No. Randomness includes the notion of a probability distribution. Bruce -- 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 on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLQO-xHuH%3DWohKMz_tOZxJauj7%2BUj%2Bmz%2BdQhxP4yscCgYQ%40mail.gmail.com.
