On Monday, October 7, 2019 at 6:13:46 PM UTC-5, Lawrence Crowell wrote: > > On Monday, October 7, 2019 at 4:21:27 PM UTC-5, John Clark wrote: >> >> As far as I know dispite lots of talk about it I'm STILL the only one on >> the list that has actually read Carroll's new book, but he gave an >> excellent Google talk about it on Friday so maybe his critics will at >> least watch that; after all even an abbreviated Cliff Notes knowledge of a >> book is better than no knowledge at all. >> >> Sean Carroll's Google talk about his new book "Something Deeply Hidden" >> <https://www.youtube.com/watch?v=F6FR08VylO4&t=1314s> >> >> John K Clark >> > > I have read Carroll and Sebens' paper on this, which is more rigorous and > less qualitative. I honestly do not have a yay or nay opinion on this. It > is something to store away in the mental toolbox. Quantum interpretations > are to my thinking unprovable theoretically and not falsifiable > empirically. > > LC >
Here is the Schrödinger equation [Wikipedia] in a historical context: The Schrödinger equation is not the only way to study quantum mechanical systems and make predictions. The other formulations of quantum mechanics include matrix mechanics <https://en.wikipedia.org/wiki/Matrix_mechanics>, introduced by Werner Heisenberg <https://en.wikipedia.org/wiki/Werner_Heisenberg>, and the path integral formulation <https://en.wikipedia.org/wiki/Path_integral_formulation>, developed chiefly by Richard Feynman <https://en.wikipedia.org/wiki/Richard_Feynman>. Paul Dirac <https://en.wikipedia.org/wiki/Paul_Dirac> incorporated matrix mechanics and the Schrödinger equation into a single formulation. Main article: Interpretations of quantum mechanics <https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics> The Schrödinger equation provides a way to calculate the wave function of a system and how it changes dynamically in time. However, the Schrödinger equation does not directly say *what*, exactly, the wave function is. Interpretations of quantum mechanics <https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics> address questions such as what the relation is between the wave function, the underlying reality, and the results of experimental measurements. An important aspect is the relationship between the Schrödinger equation and wave function collapse <https://en.wikipedia.org/wiki/Wave_function_collapse>. In the oldest Copenhagen interpretation <https://en.wikipedia.org/wiki/Copenhagen_interpretation>, particles follow the Schrödinger equation *except* during wave function collapse, during which they behave entirely differently. The advent of quantum decoherence theory <https://en.wikipedia.org/wiki/Quantum_decoherence> allowed alternative approaches (such as the Everett many-worlds interpretation <https://en.wikipedia.org/wiki/Everett_many-worlds_interpretation> and consistent histories <https://en.wikipedia.org/wiki/Consistent_histories>), wherein the Schrödinger equation is *always* satisfied, and wave function collapse should be explained as a consequence of the Schrödinger equation. In 1952, Erwin Schrödinger <https://en.wikipedia.org/wiki/Erwin_Schr%C3%B6dinger> gave a lecture during which he commented, Nearly every result [a quantum theorist] pronounces is about the probability of this *or* that or that ... happening—with usually a great many alternatives. The idea that they be not alternatives but *all* really happen simultaneously seems lunatic to him, just *impossible.* David Deutsch <https://en.wikipedia.org/wiki/David_Deutsch> regarded this as the earliest known reference to a many-worlds interpretation of quantum mechanics, an interpretation generally credited to Hugh Everett III <https://en.wikipedia.org/wiki/Hugh_Everett_III>,[ <https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation#cite_note-14> while Jeffrey A. Barrett <https://en.wikipedia.org/wiki/Jeffrey_A._Barrett> took the more modest position that it indicates a "similarity in ... general views" between Schrödinger and Everett. Any Rashomon "interpretation" of this probability-calculating formula [the probability of this *or* that or that - as Schrödinger <https://en.wikipedia.org/wiki/Erwin_Schr%C3%B6dinger>] in terms of an underlying should not be presented to the public on a book tour as settled truth. There are the alternatives noted above, and unless some new observations are made, there are a dozen (or even dozens) of views that one can adopt. To a probability theorist though, Carroll appears something like a pseudoscientist. I just can't see how his attempt at a probability measure on "many worlds" works, vs. "a sample space Ω of possible histories." Hilbert Spaces from Path Integrals - https://arxiv.org/abs/1002.0589 @philipthrift -- 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 everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/71c82f4c-54d3-4382-a9c1-6c2ebd697d04%40googlegroups.com.
