On Sun, Jul 11, 2021 at 8:27 AM smitra <[email protected]> wrote: > On 10-07-2021 21:41, 'Brent Meeker' via Everything List wrote: > > On 7/10/2021 1:19 AM, Bruno Marchal wrote: > >> So, in general we can conclude by generalizing this to any large > >> number of particles that even with what we consider to be permanent > >> records, you don't get rid of the theoretical possibility of > >> interference between the sectors where those records are different. > > > > We can if the universe is expanding faster than light beyond the Hubble > > radius. > > > > The expansion of the universe is irrelevant. The information needed to > see the interference pattern continues to exist outside the horizon when > it isn't accessible to us anymore. And this is irrelevant for the > discussions about observations in quantum mechanics. If an observer > performs a measurement and the claim is that this is a unitary process > with the observer evolving into a superposition, while the objection > against this claim is that infrared photons are escaping and will > eventually move beyond the Hubble volume, then these photons will still > not have escaped beyond the Hubble horizon by the time the observer is > aware of the results of the experiment. So, whether or not the photons > will eventually no longer be accessible, cannot be relevant. >
Once the photons escape from the immediate environs of the experiment, they are not recoverable. Try shining a torch at night to illuminate a tree. Now try to stop the illumination already present. You can stop future illumination by covering the torch, or switching it off. But once the tree is illuminated it is not reversible. The expansion of the universe, and the existence of the Hubble horizon, just makes the irreversibility more obvious. 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/CAFxXSLSjqpTNcrnEWiHLsjfV_JgTOooBB-0uaW27DdByMTWrWQ%40mail.gmail.com.
