15 views

Skip to first unread message

Dec 18, 2021, 6:01:20 PM12/18/21

to atvoid-2, everything list

Sabine Hossenfelder is going on about superdeterminism yet again. Her

aim, clearly, is to show that physics is entirely local, and that the

non-locality usually associated with violations of the Bell inequalities

does not exist -- so that all physics is entirely local and completely

determined.

http://backreaction.blogspot.com/2021/12/does-superdeterminism-save-quantum.html

While I would agree with Sabine that the question of non-locality has

nothing to do with 'free will', whatever that might be, I do not agree

with her general conclusions. The trouble is that the formalism of

quantum mechanics requires a non-separable function for the description

of the entangled state. A simple argument would go along the lines that

if statistical independence is always correct, then all wave functions

must be separable. Since they are not, statistical independence must be

violated, or else the formalism of quantum mechanics is completely wrong.

I do not think that Hossenfelder and her associates have ever developed

an alternative quantum formalism that incorporates their ideas about

hidden variables. Until we have some such formalism that we can examine

and compare with experiment, Sabine is just blowing smoke here.

She dodges the real issues by discussing superdeterminism in terms of a

simple case, such as the double slit experiment. But the real issues

with statistical independence -- the ability of experimenters to freely

and independently choose what spin state to measure -- arise in full

force only for entangled systems. In order to get a local explanation of

violations of Bell inequalities, one must claim that which measurement

is made is predetermined, outside the local control of the individual

experimenter. Vague statements that the result obtained depends on the

measurement made are either trivial or else meaningless without a

developed quantum formalism that incorporates the requires hidden variables.

Bruce

aim, clearly, is to show that physics is entirely local, and that the

non-locality usually associated with violations of the Bell inequalities

does not exist -- so that all physics is entirely local and completely

determined.

http://backreaction.blogspot.com/2021/12/does-superdeterminism-save-quantum.html

While I would agree with Sabine that the question of non-locality has

nothing to do with 'free will', whatever that might be, I do not agree

with her general conclusions. The trouble is that the formalism of

quantum mechanics requires a non-separable function for the description

of the entangled state. A simple argument would go along the lines that

if statistical independence is always correct, then all wave functions

must be separable. Since they are not, statistical independence must be

violated, or else the formalism of quantum mechanics is completely wrong.

I do not think that Hossenfelder and her associates have ever developed

an alternative quantum formalism that incorporates their ideas about

hidden variables. Until we have some such formalism that we can examine

and compare with experiment, Sabine is just blowing smoke here.

She dodges the real issues by discussing superdeterminism in terms of a

simple case, such as the double slit experiment. But the real issues

with statistical independence -- the ability of experimenters to freely

and independently choose what spin state to measure -- arise in full

force only for entangled systems. In order to get a local explanation of

violations of Bell inequalities, one must claim that which measurement

is made is predetermined, outside the local control of the individual

experimenter. Vague statements that the result obtained depends on the

measurement made are either trivial or else meaningless without a

developed quantum formalism that incorporates the requires hidden variables.

Bruce

Dec 18, 2021, 10:55:50 PM12/18/21

to everyth...@googlegroups.com

The quotes of presumably otherwise rational people saying that determinism precludes free will and therefore science are quite shocking.

Stathis Papaioannou

Dec 19, 2021, 3:59:26 AM12/19/21

to everyth...@googlegroups.com

'Vague statements that the result obtained depends on the

-Bruce

Indeed. But somebody wrote something, in 1988.

https://sci-hub.mksa.top/10.1007/bf00670750

measurement made are either trivial or else meaningless without a

developed quantum formalism that incorporates the requires hidden variables.'
-Bruce

Indeed. But somebody wrote something, in 1988.

https://sci-hub.mksa.top/10.1007/bf00670750

Dec 19, 2021, 5:09:24 AM12/19/21

to Everything List

So where is the 'developed quantum formalism that incorporates the required hidden variables'?

Bruce

Dec 19, 2021, 6:25:57 AM12/19/21

to everyth...@googlegroups.com

In (7) (Brans, 1988) the density for hidden variables depends not only on the state of the particle pair but also on the detector settings a and b. (I'm not a fan of superdeterminism. Somedody pointed out that concepts like falsifiability, isolated system, repetition of an experiment, random measurement error, are impossible. So, the original motivation for superdeterminism -

saving locality, I guess - is not present in the picture of the world we get from

it.)

--

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-li...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLQjo3%2BbpGdLvXLr%3Dg3P_e7LXGSRWHSCw26NtRoR-b9s9Q%40mail.gmail.com.

Dec 19, 2021, 4:41:10 PM12/19/21

to Everything List

On Sun, Dec 19, 2021 at 10:25 PM 'scerir' via Everything List <everyth...@googlegroups.com> wrote:

In (7) (Brans, 1988) the density for hidden variables depends not only on the state of the particle pair but also on the detector settings a and b. (I'm not a fan of superdeterminism. Somedody pointed out that concepts like falsifiability, isolated system, repetition of an experiment, random measurement error, are impossible. So, the original motivation for superdeterminism -

saving locality, I guess - is not present in the picture of the world we get from

it.)

The Brans paper, at best, shows that the idea of superdeterminism is not inconsistent. In other words, if a fully developed quantum formalism incorporating superdeterminism were developed, it would work as advertised. The trouble is that no such formalism has been developed. And simple reflection shows that it is unlikely that any such formalism could exist -- for instance, it would require an infinite number of inputs in the form of initial conditions.

Bruce

Reply all

Reply to author

Forward

0 new messages

Search

Clear search

Close search

Google apps

Main menu