> On 11 Sep 2019, at 01:30, Bruce Kellett <[email protected]> wrote: > > From: Bruno Marchal <[email protected] <mailto:[email protected]>> >>> On 8 Sep 2019, at 13:59, Bruce Kellett <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> On Sun, Sep 8, 2019 at 8:45 PM Bruno Marchal <[email protected] >>> <mailto:[email protected]>> wrote: >>> On 7 Sep 2019, at 08:04, Bruce Kellett <[email protected] >>> <mailto:[email protected]>> wrote: >>>> On Sat, Sep 7, 2019 at 3:54 PM 'Brent Meeker' via Everything List >>>> <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> On 9/6/2019 10:21 PM, Philip Thrift wrote: >>>>> Sean Carroll is on a nationwide speaking tour now evangelizing Many >>>>> Worlds. >>>>> >>>>> What is the predictive power of Many Worlds? >>>> >>>> None, unless someone can figure out how to derive Born's rule from >>>> it...which I think is impossible. But it does go a way toward making the >>>> story of measurement more consistent. >>>> >>>> Amplify the above statement. >>>> >>>> Even Zurek, who starts from a many worlds perspective, thinks that >>>> ultimately one can abandon the non-seen worlds as irrelevant. >>> >>> But irrelevant does not mean false. So it is irrelevant in physics, but it >>> is not irrelevant in theology. It might plays a role concerning the >>> interpretation of death, like with quantum immortality. >>> >>> If the only relevance you can find for many worlds is quantum immortality, >>> then many worlds is indeed dead. Quantum immortality has been shown many >>> times to be a complete nonsense. >> >> Really. I did not known that. Could you give the references. > Follow the Wikipedia entry on quantum suicide. > That is not what I mean by a reference.
> The main problem with the idea of quantum immortality is that not all > life-threatening events that one can encounter are in the form of alternative > outcomes to quantum processes. > The point is that at each instant we have an infinity (plausibly aleph_1, at least aleph_0) alternate accessible histories, and it is up to you to prove that when we die in some history, we die in all. That is dubious, because there are always consistent extensions (but of course I use Mechanism here). > Quantum suicide is an attempt to overcome this problem by linking death or > survival directly to the outcome of a particular quantum process. David > Deutsch was sceptical that this worked: > 'Physicist David Deutsch <https://en.wikipedia.org/wiki/David_Deutsch>, > though a proponent of the many-worlds interpretation, states regarding > quantum suicide that "that way of applying probabilities does not follow > directly from quantum theory, as the usual one does. It requires an > additional assumption, namely that when making decisions one should ignore > the histories in which the decision-maker is absent....[M]y guess is that the > assumption is false." > Tegmark was also doubtful about the chances for quantum immortality -- > pointing out that dying is rarely a binary event; it is more often the result > of a slow cumulative process. > > Another argument that has been given here before is that if quantum > immortality is true, then we should expect to see a number of people who are > considerably older than the normal life expectancy > That makes no sense. The argument rest typically on the first person, not the first person plural. > -- and we do not see people who are two or three hundred years old. > Just compute the probability. That would be akin to a white rabbit. The argument concerns only the first person experience, and it can involved amnesia. > Even if the probabilities are very low, there have been an awful lot of > people born within the last 500 or so years -- some must have survived on our > branch if this scenario is true. > The probability is the same as the one with a beam splitter (some “half mirror”) and all photons going on the same path. Nobody as seen this. But if you kill yourself if the photon go in the non rare path, you will see the photon going on the rare path with probability one, by the cul-de-sac principle (again, I use, like Everett; the mechanist hypothesis). > >> That would be an indice that Mechanism is false, given that quantum >> immortality is deduce here from the already much more obvious arithmetical >> immortality, which is disturbing, but hard to avoid. > > Well, as you know, I consider mechanism to be false in any case, so the > failure of quantum immortality is no news to me. > > Mechanism implies a form of computational immortality. Non mechanism is neutral, especially in absence of some non mechanist theory of mind (and matter). > >> Are you saying that quantum suicide is also a non-sense (metaphysically, it >> is a practical non-sense). > > It relates to the standard problem for Many worlds theory -- if a quantum > experiment with binary outcomes is performed many times, there will always be > observers who see major deviations from the expected quantum probabilities. > In which case, we cannot rely on repeated experiments to be a reliable > indicator of the underlying probabilities. > That confuses the first person plural with the first person singular experience. > And if you cannot use long-run relative frequencies to estimate > probabilities, what do you use? David Wallace attempts to get around this by > simply dismissing the outliers as "irrelevant" (You, I recall, have made a > similar argument.) Wallace even suggests that these outlying sets of results > are "lost in the quantum noise", but he does not elaborate on this totally > stupid claim. (Wallace, in "The Emergent Multiverse" (2012)) > If something has a low probability, the exception will be low, independently of the fact that all outcomes are realised or not. > >> If the reference assume a wave packet reduction, or a way “matter” can >> interfere with the computations in arithmetic, no need to give the >> references. It is just working in different theories. > None of this has anything to do with wave-packet reduction, so you can rest > easy. > > You lost me here. With the wave reduction, there is just no quantum immortality at all, nor even quantum suicide. I guess I mess something. The only “reasonable” critics was the one done by Jacques Mallah on this list, which claims that if QI or MI is correct, we should expect to be very old. But Quentin answered this validly: we expect in all situation to be just a bit older than where we remember coming from, and the paradox comes from a confusing between relative and absolute self-sampling on the states or histories. Typically, also, old and young are not absolute concept. With mechanism or quantum mechanics without collapse, we can say that we are always young. Bruno > 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] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/f239f2e2-d9ec-96ba-aba6-75d99c9856ac%40optusnet.com.au > > <https://groups.google.com/d/msgid/everything-list/f239f2e2-d9ec-96ba-aba6-75d99c9856ac%40optusnet.com.au?utm_medium=email&utm_source=footer>. -- 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/D407AAF2-059F-409C-B0C4-538B26EC6954%40ulb.ac.be.
