On 1/12/2017 10:20 am, [email protected] wrote:
On Thursday, November 30, 2017 at 11:16:07 PM UTC, [email protected]
wrote:
On Thursday, November 30, 2017 at 9:47:37 PM UTC, Bruce wrote:
On 30/11/2017 10:59 pm, [email protected] wrote:
*How can MWI be deterministic if it can't tell us what
outcome we will observe in this world, or any other? AG*
Because MWI says that all outcomes are realized, each in a
separate world. Apparent randomness comes about because we
don't know which world we will end up in (though we actually
end up in all the worlds, so we, or our duplicates, observe
all possible outcomes).
Bruce
*
OK. I wouldn't use "deterministic" to describe that situation, but
that's neither here nor there.
More important is Brent's reply to my question which started this
discussion thread. He stated that a deterministic ONE WORLD version of
QM would have dire effects, such as the future influencing the past.
His exact words are in the 2nd message in this discussion. You don't
seem to share this view. I know that Bohm developed a deterministic
version of QM which is expressly non-local and not covariant. I don't
think it's what Brent was referring to.
Also, I noticed that Bruno, our resident enthusiast of arithmetic as
the solution to all enigmas, stated that Weinberg showed that a
non-linear SWE to explain collapse would imply that the laws of
thermodynamics are flawed. Is this your understanding?*
I think the problem is that you are using a different understanding of
the term 'deterministic'. I think you mean that a deterministic theory
is one that would enable us to preict the result of any measurement --
the result that /we/ would see. QM doesn't do that, but MWI is
deterministic in that the SE gives the future from the present by
deterministic evolution of the wave function. The downside is that it
predicts that all possible results of any measurement are obtained in
/some world or another/, but it doesn't tell us which world we will find
ourselves in, so it doesn't predict which of the possible results is the
one we will see.
Brent's point about EPR and faster-than-light signalling is slightly
different. He is saying that if you could control the results of a
polarization measurement in an EPR set up, then you could signal at
spacelike separations. Such signalling would be a bad thing in general,
and is forbidden in standard QM.
As to Bruno's comment about a non-linear SE and thermodynamics, I don't
know. I am not familiar with Weinberg's argument.
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 post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.
