On 04-05-2022 22:24, Brent Meeker wrote:

On 5/4/2022 11:36 AM, smitra wrote:On 03-05-2022 19:52, Brent Meeker wrote:On 5/3/2022 5:00 AM, smitra wrote:On 28-04-2022 07:24, Brent Meeker wrote:On 4/26/2022 5:32 PM, smitra wrote:On 27-04-2022 01:37, Bruce Kellett wrote: On Tue, Apr 26, 2022 at 10:03 AM smitra <smi...@zonnet.nl> wrote: On 24-04-2022 03:16, Bruce Kellett wrote: A moment's thought should make it clear to you that this is not possible. If both possibilities are realized, it cannot be the case that one has twice the probability of the other. In the long run, if both are realized they have equal probabilities of 1/2.The probabilities do not have to be 1/2. Suppose one millionpeopleparticipate in a lottery such that there will be exactly onewinner.The probability that one given person will win, is then one in a million. Suppose now that we create one million people using a machine and then organize such a lottery. The probability that one given newly created person will win is then also one in a million. The machine can be adjusted to create any set of persons we like, it can create one millionidentical persons, or almost identical persons, or totallydifferentpersons. If we then create one million almost identical persons,theprobability is still one one in a million. This means that thelimitof identical persons, the probability will be one in a million.Why would the probability suddenly become 1/2 if the machine issettocreate exactly identical persons while the probability would beonein a million if we create persons that are almost, but not quite identical?Your lottery example is completely beside the point.It provides for an example of a case where your logic does notapply.I think you should pay more attention to the mathematics of the binomial distribution. Let me explain it once more: If every outcome is realized on every trial of a binary process, then after the first trial, we have a branch with result 0 and a branch with result 1.After two trials we have four branches, with results 00, 01,10,and11; after 3 trials, we have branches registering 000, 001, 011,010,100, 101, 110, and 111. Notice that these branches represent all possible binary strings of length 3. After N trials, there are 2^N distinct branches, representing all possible binary sequences of length N. (This is just like Pascal's triangle) As N becomes very large, we can approximate the binomial distribution with the normal distribution, with mean 0.5 and standarddeviation that decreases as 1/sqrt(N). In other words, themajorityof trials will have equal, or approximately equal, numbers of 0s and 1s. Observers in these branches will naturally take the probability to be approximated by the relative frequencies of 0s and 1s. In other words, they will take the probability of each outcome to be 0.5.The problem with this is that you just assume that all branches are equally probable. You don't make that explicit, it's implicitly assumed, but it's just an assumption. You are simply doing branch counting.But it shows why you can't use branch counting. There's nophysicalmechanism for translating the _a_ and _b_ of _|psi> = a|0> + b|1>_ into numbers of branches. To implement that you have put it in "by hand" that the branches have weights or numerousity of _a _and _b_.This is possible, but it gives the lie to the MWI mantra of "It'sjustthe Schroedinger equation."Yes, one has to interpret the wavefunction as giving probabilities.That's still better than assuming that the physical state evolvessometimes according to the Schrödinger equations and sometimes byundergoing a nondeterministic collapse without there being anyevidence for such collapses, without even credible theoreticalmodels for it.Is there any evidence that is NOT from collapse? How does it get recorded? Where is it? A credible theoretical model is one thatpredicts the observed result...not necessarily one that satisfiesyourmetaphysical prejudices. You seem to have adopted a Platonist viewofphysics. But as Sean Carroll (a proponent of MWI) remarked, "But all human progress has come from studying the shadows on the wall."A theoretical model cannot be tied to macroscopic concepts that areknown to only give an effective description of nature.But that's not "known". It's only "known" if you assume the theoretical model...circular reasoning.

`If collapse is not effective but a real effect not due to decoherence,`

`then there is as of yet no experimental evidence for it.`

It's just like concepts in thermodynamics that can be explained in amore fundamental way using statistical physics. No one objects todoing that on the grounds of any practical impossibility of buildingmolecular-scale heat engines.But the consequences of thermodynamics are confirmed by observation. MWI puts them where they are, in principle, unobservable.

`Real collapse would have clear observational consequences. There is no`

`experimental evidence for collapse. A real collapse would also violate`

`QM, despite being part of the postulated of QM as traditionally`

`formulated, due to the Schrödinger equation not being universally valid.`

Saibal

Brent

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