On Wed, Aug 7, 2019 at 11:52 PM Bruno Marchal <[email protected]> wrote:
> On 7 Aug 2019, at 15:18, Bruce Kellett <[email protected]> wrote: > > On Wed, Aug 7, 2019 at 7:48 PM Bruno Marchal <[email protected]> wrote: > >> On 7 Aug 2019, at 06:08, Bruce Kellett <[email protected]> wrote: >> >> >> Unitary evolution is an assumption. >> >> Yes. It is called Quantum Mechanics (without collapse). >> > > No, it is actually just the Schroedinger equation. This works in certain > circumstances, but its universal validity has never been tested -- it is > just an unproven assumption. > > > All theories about any reality are “just” unproven assumption. But that is > why we test it, and all modified QM so as to make the superposition > disappear somewhere have been refuted. > No, not all have been refuted. What has been refuted is the idea that you can observe a superposition between macroscopic objects (such as dead and alive cats). All attempts to produce such superpositions have failed. The fact that you can write down an equation that seems to express such a superposition does not mean that the superposition actually exists. Explaining the absence of such superpositions is the central problem in the foundations of quantum mechanics. It is the "preferred basis problem" in essence. And this is the problem the Everettt did not solve. 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/CAFxXSLT244s0AN%3DKNL5ZPeb3sFNZxCzT%2BzLR2-PA93vPoqQkEw%40mail.gmail.com.
