subject:"Probability"

On Tue, Nov 22, 2022 at 12:37 AM Bruce Kellett 
wrote:

*> Temporal ordering implies that we have actually completed an infinite
> series of tosses, and that is never possible. *

Calculus always involves an infinite series and we can't calculate all of
those, but we can figure out if an infinite series converges or not and if
it does what it converges to. Do you think calculus is not "justified"?

*> We then have to assume that the first N trials form a "typical" subset,
> and how do you ever justify that?*

Physics has something mathematics does not, experimentation. So the answer
to your question is simple, if it works it's justified.

John K ClarkSee what's on my new list at  Extropolis

hxc

-- 
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/CAJPayv2FsT_RTr-apQo_fRWiFdcbgtWRu3BWMGarDeFpvxGrSA%40mail.gmail.com.

Re: Physics Without Probability

On Mon, Nov 21, 2022 at 8:54 PM Bruce Kellett  wrote:

*> What is a probability?*


Something that is always positive and never negative, and always adds up to
exactly 1, and something that enables us to make the best possible guess
about what will happen when faced with situations in which we have
incomplete knowledge.

John K ClarkSee what's on my new list at  Extropolis
<https://groups.google.com/g/extropolis>
q0o

-- 
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/CAJPayv2%3DYsgRk0O1U6VfEDp-%2BPhTJsUwRiVpDQ_avHXbKhmuqQ%40mail.gmail.com.

Re: Physics Without Probability

On Mon, Nov 21, 2022 at 7:38 PM Bruce Kellett  wrote:

> *Testing is not a theoretical grounding of the theory.*
>

WHAT! This is physics not pure mathematics, in science theory must always
take the backseat, experiment is the ultimate judge about who is correct.
It makes no difference how beautiful a theory is, testing is the ONLY way
to ground a theory. It's true that Many Worlds has not been grounded by
experimentation but it has come closer to doing so than any other quantum
interpretation if you don't count "shut up and calculate" and its
euphemistic twin Quantum Bayesianism. And I don't count them because
they're not really interpretations, they're just giving up.

 John K ClarkSee what's on my new list at  Extropolis

jgu

-- 
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/CAJPayv1w3Ru5oxKiZoS0y8dWB8yjHDttY02BgTgxbvd_FOiCVw%40mail.gmail.com.

Re: Physics Without Probability

On Mon, Nov 21, 2022 at 6:31 PM Brent Meeker  wrote:


> >> some call Many Worlds bare bones, no nonsense quantum mechanics, it
>> has no silly bells and whistles cluttering things up. And that's the sort
>> of thing William of Ockham would approve of.
>
>
> * > It has an infinite number of other worlds, most differing from this
> world only in unobservable ways.*
>

Yes.


>  >
> * In comparison, taking the Born rule to mean what it says seems like
> modest addition to the theory.*
>

>From experimentation we know for a fact the Born Rule means what it says
and is correct, but if you are not satisfied with the "shut up and
calculate" philosophy and if there were NOT "*an infinite number of other
worlds most differing from this world only in unobservable ways*" then
you're out of luck; if that's true I don't think there would be any hope of
achieving an intuitive understanding of why the Born Rule is correct, and
so you must instead just learn to be satisfied with shut up and calculate.
After all, many philosophers, including some really great ones like Dirac,
are just not interested in philosophy.

  John K ClarkSee what's on my new list at  Extropolis


6te

-- 
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/CAJPayv0Xev57XFzof7pC2rRVCVFXbddH%2BzS8%3DoK%3DQ2GYxZWnQA%40mail.gmail.com.

Re: Physics Without Probability




On 11/21/2022 9:37 PM, Bruce Kellett wrote:

On Tue, Nov 22, 2022 at 3:57 PM Jesse Mazer  wrote:

What about the idea of grounding the notion of probability in
terms of the frequency in the limit of a hypothetical infinite
series of trials, what philosophers call "hypothetical
frequentism"? The Stanford Encyclopedia of Philosophy discussion
of this at
https://plato.stanford.edu/entries/probability-interpret/#FreInt
notes the objection that the limit depends on the order we count
the trials, but it seems pretty natural to use temporal ordering
in this case. Aside from the philosophical objection that we don't
have any clear a priori justification for privileging temporal
ordering in this way, are there any objections of a more technical
nature to hypothetical frequentism with temporal ordering
(scenarios where it would give you a different answer from
    standard probability theory), or are the objections purely
philosophical?


The standard trouble with the hypothetical infinite series of trials 
is that we have to define the probability in terms of subsequences, 
since we can't actually realize an infinite series. In order for these 
subsequences to give (approximately) the same probability as the 
hypothetical infinite series, the subsequences have to be "typical", 
and "typical" can only be defined probabilistically, so we are back 
with the problem of circularity.


Temporal ordering of the sequence is also somewhat arbitrary, since if 
we order a series of coin tosses according to magnitude (heads = 0, 
tails = 1), then most subsequences will not be "typical" and will give 
spurious results. Temporal ordering implies that we have actually 
completed an infinite series of tosses, and that is never possible. We 
then have to assume that the first N trials form a "typical" subset, 
and how do you ever justify that?


We did a lot statistical mechanics taking the limit of many 
states/particles etc.  without worrying that the experiments were never 
infinite.


Brent

--
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/910d6ecd-b692-c464-856c-35873c118bb9%40gmail.com.

Re: Physics Without Probability

2022-11-21 Thread Jesse Mazer

I don't see why you need the subsequences to be "typical" if you are using
temporal ordering--for example if you want to define the probability of
heads, you can define f_N as the fraction of flips that came up heads in
the first N trials of the temporal ordering, then consider the limit as N
approaches infinity. Any specific value of N may be highly atypical while
the infinite limit is still 1/2. So again, is the objection just the
philosophical one that temporal ordering seems "arbitrary", and/or some
kind of philosophical objection to defining probability in terms of
a complete infinite series of trials even though this is explicitly a
"hypothetical" definition?

On Tue, Nov 22, 2022 at 12:37 AM Bruce Kellett 
wrote:

> On Tue, Nov 22, 2022 at 3:57 PM Jesse Mazer  wrote:
>
>> What about the idea of grounding the notion of probability in terms of
>> the frequency in the limit of a hypothetical infinite series of trials,
>> what philosophers call "hypothetical frequentism"? The Stanford
>> Encyclopedia of Philosophy discussion of this at
>> https://plato.stanford.edu/entries/probability-interpret/#FreInt notes
>> the objection that the limit depends on the order we count the trials, but
>> it seems pretty natural to use temporal ordering in this case. Aside from
>> the philosophical objection that we don't have any clear a priori
>> justification for privileging temporal ordering in this way, are there any
>> objections of a more technical nature to hypothetical frequentism with
>> temporal ordering (scenarios where it would give you a different answer
>> from standard probability theory), or are the objections purely
>> philosophical?
>>
>
> The standard trouble with the hypothetical infinite series of trials is
> that we have to define the probability in terms of subsequences, since we
> can't actually realize an infinite series. In order for these subsequences
> to give (approximately) the same probability as the hypothetical infinite
> series, the subsequences have to be "typical", and "typical" can only be
> defined probabilistically, so we are back with the problem of circularity.
>
> Temporal ordering of the sequence is also somewhat arbitrary, since if we
> order a series of coin tosses according to magnitude (heads = 0, tails =
> 1), then most subsequences will not be "typical" and will give spurious
> results. Temporal ordering implies that we have actually completed an
> infinite series of tosses, and that is never possible. We then have to
> assume that the first N trials form a "typical" subset, and how do you ever
> justify that?
>
> 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 everything-list+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/everything-list/CAFxXSLQSx91DMcoNZfcGVWwJ_gMBd1pv2Xk%3DgBYQ3eij_owcvg%40mail.gmail.com
> <https://groups.google.com/d/msgid/everything-list/CAFxXSLQSx91DMcoNZfcGVWwJ_gMBd1pv2Xk%3DgBYQ3eij_owcvg%40mail.gmail.com?utm_medium=email_source=footer>
> .
>

-- 
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/CAPCWU3K4Yj%3DFQd8C%3DckrOXqjMTq7%2B3dhQBLMhPpJ4KdiRyBysQ%40mail.gmail.com.

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 3:57 PM Jesse Mazer  wrote:

> What about the idea of grounding the notion of probability in terms of the
> frequency in the limit of a hypothetical infinite series of trials, what
> philosophers call "hypothetical frequentism"? The Stanford Encyclopedia of
> Philosophy discussion of this at
> https://plato.stanford.edu/entries/probability-interpret/#FreInt notes
> the objection that the limit depends on the order we count the trials, but
> it seems pretty natural to use temporal ordering in this case. Aside from
> the philosophical objection that we don't have any clear a priori
> justification for privileging temporal ordering in this way, are there any
> objections of a more technical nature to hypothetical frequentism with
> temporal ordering (scenarios where it would give you a different answer
> from standard probability theory), or are the objections purely
> philosophical?
>

The standard trouble with the hypothetical infinite series of trials is
that we have to define the probability in terms of subsequences, since we
can't actually realize an infinite series. In order for these subsequences
to give (approximately) the same probability as the hypothetical infinite
series, the subsequences have to be "typical", and "typical" can only be
defined probabilistically, so we are back with the problem of circularity.

Temporal ordering of the sequence is also somewhat arbitrary, since if we
order a series of coin tosses according to magnitude (heads = 0, tails =
1), then most subsequences will not be "typical" and will give spurious
results. Temporal ordering implies that we have actually completed an
infinite series of tosses, and that is never possible. We then have to
assume that the first N trials form a "typical" subset, and how do you ever
justify that?

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLQSx91DMcoNZfcGVWwJ_gMBd1pv2Xk%3DgBYQ3eij_owcvg%40mail.gmail.com.

Re: Physics Without Probability

2022-11-21 Thread Jesse Mazer

What about the idea of grounding the notion of probability in terms of the
frequency in the limit of a hypothetical infinite series of trials, what
philosophers call "hypothetical frequentism"? The Stanford Encyclopedia of
Philosophy discussion of this at
https://plato.stanford.edu/entries/probability-interpret/#FreInt notes the
objection that the limit depends on the order we count the trials, but it
seems pretty natural to use temporal ordering in this case. Aside from the
philosophical objection that we don't have any clear a priori justification
for privileging temporal ordering in this way, are there any objections of
a more technical nature to hypothetical frequentism with temporal ordering
(scenarios where it would give you a different answer from standard
probability theory), or are the objections purely philosophical?

On Mon, Nov 21, 2022 at 7:33 PM Bruce Kellett  wrote:

> On Tue, Nov 22, 2022 at 11:08 AM Brent Meeker 
> wrote:
>
>> He's wrong that frequentism does not empirically support probability
>> statements.  He goes off on a tangent by referring to "other gamblers".
>> Nothing in physics is certain, yet Deutsch takes a bunch of definite
>> assertions and claims they alone are the real physics.
>>
>
> His critique of frequentism is just a recap of arguments that are well
> known -- you cannot ground probability theory in frequentism, or the idea
> that probabilities are nothing more than ratios of long-run frequencies.
> Long-run frequencies might approximate the probabilities, but they cannot
> be used to ground probability theory -- for well known reasons. I agree
> that he goes off on a number of irrelevant tangents, and he is wrong to
> suppose that frequentism is a main-stream theory of probability (at least,
> these days).
>
> Bruce
>
> On 11/20/2022 4:28 PM, Bruce Kellett wrote:
>>
>> On Mon, Nov 21, 2022 at 2:52 AM smitra  wrote:
>>
>>> Probability cannot be a fundamental concept in physics as explained
>>> here:
>>>
>>> https://www.youtube.com/watch?v=wfzSE4Hoxbc
>>
>>
>> I'm afraid Deutsch is a bit too glib in this lecture. He hasn't, despite
>> his best efforts, removed probability from physics. For example, in quantum
>> mechanics, he has not explained why, if one measures the z-spin of a
>> spin-half particle prepared in an eigenstate of x-spin, one gets only one
>> result -- either z-spin-up or z-spin-down. If one has eliminated
>> probability, one should be able to explain which result one gets, and why.
>> It is no solution to say that with many-worlds, that both results are
>> obtained by disjoint copies of the experimenter. The experimenter is just
>> one copy, and one would have to explain the result for each individual
>> separately. Many worlds does not explain why I, for example, see only
>> z-spin-up and not z-spin-down. To make sense of that, we need a viable
>> concept of probability and the Born rule.
>>
>> 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 everything-list+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/everything-list/CAFxXSLQgSxrbySZNq-1HOFOu_7aie5y3Av3bMcYvB0Gp7hyBHg%40mail.gmail.com
> <https://groups.google.com/d/msgid/everything-list/CAFxXSLQgSxrbySZNq-1HOFOu_7aie5y3Av3bMcYvB0Gp7hyBHg%40mail.gmail.com?utm_medium=email_source=footer>
> .
>

-- 
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/CAPCWU3LS%2BbyjV4i8_m6trB4UM9xUOHK0wbQDz%2Bk2sPSX%2BeE3ng%40mail.gmail.com.

Re: Physics Without Probability

On 11/21/2022 5:54 PM, Bruce Kellett wrote:
On Tue, Nov 22, 2022 at 12:44 PM Brent Meeker
wrote:

On 11/21/2022 4:38 PM, Bruce Kellett wrote:

On Tue, Nov 22, 2022 at 11:35 AM Brent Meeker
wrote:

But frequencies are how we test probabilistic theories.

Testing is not a theoretical grounding of the theory.

It's not the axiomatic ground of Kolmogorov's theory. But so
what? We tested Euclid's theory of geometry by making
measurements which weren't in his axioms. That doesn't mean
Euclid's wasn't a good theory of geometry. I can see Deutsch
crossing off Pythagora's theorem saying, "No matter how precise
our instruments they only yield rational quantities!" Physics is
not mathematics and it's never going to have data to infinitely
many decimal places. That frequencies only yield rational number
approximations to Born rule predictions doesn't seem like a big
deal to me.

What is a probability? We can't define it as a limiting frequency,
since repeats of a sequence of measurements of a spin are going to
give a range of answers for the frequency of spin-up, and this
sequence converges to some limit only in probability. That is then
circular -- probability is defined in terms of probability.

But in fact we will reject a theory that predicts that the observed data
is very improbable.

Perhaps 'probability' is a primitive concept -- not definable in terms
of anything physical. Nevertheless, like language, it is essential for
our understanding of our experience of the world.

I think it is term that refers to different things in different
contexts, like "energy" or "distance". It has a definition is
mathematics, but that's not the same as it's operational definition in
physics or law or finance. It can be defined in terms of symmetry in
physics, as a die is fair if the probability of each face is independent
and = 1/6. Then this can be tested under frequentist definitions. How
many throws yielded :: out of 10,000 trials? If you're playing craps
then you adopt a degree of belief that :: will appear 1/6 of the time
and being a decision theorist you bet accordingly.

Brent

Re: Physics Without Probability





On 11/21/2022 6:15 PM, smitra wrote:

On 22-11-2022 02:47, Brent Meeker wrote:

On 11/21/2022 5:12 PM, smitra wrote:
The problem lies with the notion of probability, he explains here 
that it cannot refer to anything in the physics world as an exact 
statement:


https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

That's then a problem for a fundamental theory of physics as such a 
theory must refer to statements about nature that are exactly true.


Who says so?  Physics never makes exact measurements.  Why should the
theory do something that the physics can't?  Deutsch is like the
scholastics, he thinks physics is just a branch of mathematical logic.

Brent


But physics cannot implement a rigorous notion of probability. So, 
that then makes QM in the traditional formulation problematic.


Physics "implements" things operationally.  Probability's operational 
meaning in physics is frequentist.  That this differs from the axiomatic 
foundation of measure theory is no more surprising than physics 
measurements are always rational values while the theories are written 
in real numbers.  Does that make Newtonian mechanics "problematic"?  Is 
this a new revelation that physics is not mathematics?


Brent


Saibal



--
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/eab5e915-459f-322e-1bad-3bd6bba6bc04%40gmail.com.

Re: Physics Without Probability


On 22-11-2022 02:47, Brent Meeker wrote:

On 11/21/2022 5:12 PM, smitra wrote:
The problem lies with the notion of probability, he explains here that 
it cannot refer to anything in the physics world as an exact 
statement:


https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

That's then a problem for a fundamental theory of physics as such a 
theory must refer to statements about nature that are exactly true.


Who says so?  Physics never makes exact measurements.  Why should the
theory do something that the physics can't?  Deutsch is like the
scholastics, he thinks physics is just a branch of mathematical logic.

Brent


But physics cannot implement a rigorous notion of probability. So, that 
then makes QM in the traditional formulation problematic.


Saibal

--
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/b12a7a8595e6646a11c323c3af6a41df%40zonnet.nl.

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 1:05 PM smitra  wrote:

> On 22-11-2022 02:45, Bruce Kellett wrote:
> > On Tue, Nov 22, 2022 at 12:12 PM smitra  wrote:
> >
> >> The problem lies with the notion of probability, he explains here
> >> that
> >> it cannot refer to anything in the physics world as an exact
> >> statement:
> >>
> >> https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s
> >>
> >> That's then a problem for a fundamental theory of physics as such a
> >> theory must refer to statements about nature that are exactly true.
> >
> > No statements in physics are exactly true.
> >
> > Bruce
> >
>
> The problem with probability is actually the other way around. It's
> impossible to rigorously define probability in purely physical terms.
> Therefore the exact formulation of the laws of physics cannot refer to
> probability.
>

They can if probability is taken to be a primitive, not definable in terms
of any physical thing or process. In other words, we use probability in
physics the same way as we use mathematics. Mathematics cannot be
rigorously defined in purely physical terms -- it is defined logically in
its own terms, but it finds application in physics.

Deutsch might just as well argue that we can do physics without
mathematics.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLQPearE5G-O%2BVfWo4ys139ATz7%2BCmT51ziFaG7K_QwPjw%40mail.gmail.com.

Re: Physics Without Probability

On 22-11-2022 02:45, Bruce Kellett wrote:

On Tue, Nov 22, 2022 at 12:12 PM smitra wrote:

The problem lies with the notion of probability, he explains here
that
it cannot refer to anything in the physics world as an exact
statement:

https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

That's then a problem for a fundamental theory of physics as such a
theory must refer to statements about nature that are exactly true.

No statements in physics are exactly true.

Bruce

The problem with probability is actually the other way around. It's
impossible to rigorously define probability in purely physical terms.
Therefore the exact formulation of the laws of physics cannot refer to
probability.

Saibal

--
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/CAFxXSLQ%3D0R9tMkdiUfQ%3D4ofBwYL9eSbPibJW70YKM083YiuiQQ%40mail.gmail.com
[1].

Links:
--
[1]
https://groups.google.com/d/msgid/everything-list/CAFxXSLQ%3D0R9tMkdiUfQ%3D4ofBwYL9eSbPibJW70YKM083YiuiQQ%40mail.gmail.com?utm_medium=email_source=footer

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 12:44 PM Brent Meeker  wrote:

> On 11/21/2022 4:38 PM, Bruce Kellett wrote:
>
> On Tue, Nov 22, 2022 at 11:35 AM Brent Meeker 
> wrote:
>
>>
>> But frequencies are how we test probabilistic theories.
>>
>
> Testing is not a theoretical grounding of the theory.
>
>
> It's not the axiomatic ground of Kolmogorov's theory.  But so what?  We
> tested Euclid's theory of geometry by making measurements which weren't in
> his axioms.  That doesn't mean Euclid's wasn't a good theory of geometry.
> I can see Deutsch crossing off Pythagora's theorem saying, "No matter how
> precise our instruments they only yield rational quantities!"  Physics is
> not mathematics and it's never going to have data to infinitely many
> decimal places.  That frequencies only yield rational number approximations
> to Born rule predictions doesn't seem like a big deal to me.
>

What is a probability? We can't define it as a limiting frequency, since
repeats of a sequence of measurements of a spin are going to give a range
of answers for the frequency of spin-up, and this sequence converges to
some limit only in probability. That is then circular -- probability is
defined in terms of probability.

Perhaps 'probability' is a primitive concept -- not definable in terms of
anything physical. Nevertheless, like language, it is essential for our
understanding of our experience of the world.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLTvbeVt-pv8LPNXwi0JnT-nUzH5R1Bxu5DEftDRvju9ZA%40mail.gmail.com.

Re: Physics Without Probability

On 11/21/2022 5:12 PM, smitra wrote:
The problem lies with the notion of probability, he explains here that
it cannot refer to anything in the physics world as an exact statement:

https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

That's then a problem for a fundamental theory of physics as such a
theory must refer to statements about nature that are exactly true.

Who says so? Physics never makes exact measurements. Why should the
theory do something that the physics can't? Deutsch is like the
scholastics, he thinks physics is just a branch of mathematical logic.

Brent

Saibal

On 22-11-2022 01:08, Brent Meeker wrote:

He's wrong that frequentism does not empirically support probability
statements. He goes off on a tangent by referring to "other
gamblers". Nothing in physics is certain, yet Deutsch takes a bunch
of definite assertions and claims they alone are the real physics.

"The race is not always to the swift, nor the battle to the strong,
but that's the way to bet."
--- Damon Runyan

"In the Austin airport on the way to this meeting I noticed for sale
the October issue of a magazine called Astronomy, having on the cover
the
headline “Why You Live in Multiple Universes.” Inside I found a
report of
a discussion at a conference at Stanford, at which Martin Rees said
that
he was sufficiently confident about the multiverse to bet his dog’s
life on
it, while Andrei Linde said he would bet his own life. As for me, I
have
just enough confidence about the multiverse to bet the lives of both
Andrei
Linde and Martin Rees’s dog."
--- Steven Weinberg

Brent

On 11/20/2022 4:28 PM, Bruce Kellett wrote:

On Mon, Nov 21, 2022 at 2:52 AM smitra wrote:

Probability cannot be a fundamental concept in physics as
explained
here:

https://www.youtube.com/watch?v=wfzSE4Hoxbc

I'm afraid Deutsch is a bit too glib in this lecture. He hasn't,
despite his best efforts, removed probability from physics. For
example, in quantum mechanics, he has not explained why, if one
measures the z-spin of a spin-half particle prepared in an
eigenstate of x-spin, one gets only one result -- either z-spin-up
or z-spin-down. If one has eliminated probability, one should be
able to explain which result one gets, and why. It is no solution to
say that with many-worlds, that both results are obtained by
disjoint copies of the experimenter. The experimenter is just one
copy, and one would have to explain the result for each individual
separately. Many worlds does not explain why I, for example, see
only z-spin-up and not z-spin-down. To make sense of that, we need a
viable concept of probability and the Born rule.

https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com

[1].

[2].

Links:
--
[1]
https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com?utm_medium=emailutm_source=footer

[2]
https://groups.google.com/d/msgid/everything-list/ef67fea2-fbf8-6e1a-2b5b-3b5182515732%40gmail.com?utm_medium=email_source=footer

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 12:12 PM smitra  wrote:

> The problem lies with the notion of probability, he explains here that
> it cannot refer to anything in the physics world as an exact statement:
>
> https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s
>
> That's then a problem for a fundamental theory of physics as such a
> theory must refer to statements about nature that are exactly true.
>

No statements in physics are exactly true.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLQ%3D0R9tMkdiUfQ%3D4ofBwYL9eSbPibJW70YKM083YiuiQQ%40mail.gmail.com.

Re: Physics Without Probability

On 11/21/2022 4:38 PM, Bruce Kellett wrote:
On Tue, Nov 22, 2022 at 11:35 AM Brent Meeker
wrote:

On 11/21/2022 4:33 PM, Bruce Kellett wrote:

On Tue, Nov 22, 2022 at 11:08 AM Brent Meeker
wrote:

He's wrong that frequentism does not empirically support
probability statements. He goes off on a tangent by
referring to "other gamblers". Nothing in physics is
certain, yet Deutsch takes a bunch of definite assertions and
claims they alone are the real physics.

His critique of frequentism is just a recap of arguments that are
well known -- you cannot ground probability theory in
frequentism, or the idea that probabilities are nothing more than
ratios of long-run frequencies. Long-run frequencies might
approximate the probabilities, but they cannot be used to ground
probability theory -- for well known reasons. I agree that he
goes off on a number of irrelevant tangents, and he is wrong to
suppose that frequentism is a main-stream theory of
probability (at least, these days).

But frequencies are how we test probabilistic theories.

Testing is not a theoretical grounding of the theory.

It's not the axiomatic ground of Kolmogorov's theory. But so what? We
tested Euclid's theory of geometry by making measurements which weren't
in his axioms. That doesn't mean Euclid's wasn't a good theory of
geometry. I can see Deutsch crossing off Pythagora's theorem saying,
"No matter how precise our instruments they only yield rational
quantities!" Physics is not mathematics and it's never going to have
data to infinitely many decimal places. That frequencies only yield
rational number approximations to Born rule predictions doesn't seem
like a big deal to me.

Brent

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/everything-list/CAFxXSLTNVrzp0JRzjwLU_2qb6nosugcSoGYuhtt%3D3Edq9dLOFQ%40mail.gmail.com
<https://groups.google.com/d/msgid/everything-list/CAFxXSLTNVrzp0JRzjwLU_2qb6nosugcSoGYuhtt%3D3Edq9dLOFQ%40mail.gmail.com?utm_medium=email_source=footer>.

Re: Physics Without Probability

The problem lies with the notion of probability, he explains here that 
it cannot refer to anything in the physics world as an exact statement:


https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

That's then a problem for a fundamental theory of physics as such a 
theory must refer to statements about nature that are exactly true.


Saibal



On 22-11-2022 01:08, Brent Meeker wrote:

He's wrong that frequentism does not empirically support probability
statements.  He goes off on a tangent by referring to "other
gamblers".  Nothing in physics is certain, yet Deutsch takes a bunch
of definite assertions and claims they alone are the real physics.

"The race is not always to the swift, nor the battle to the strong,
but that's the way to bet."
--- Damon Runyan

"In the Austin airport on the way to this meeting I noticed for sale
the October issue of a magazine called Astronomy, having on the cover
the
headline “Why You Live in Multiple Universes.” Inside I found a
report of
a discussion at a conference at Stanford, at which Martin Rees said
that
he was sufficiently confident about the multiverse to bet his dog’s
life on
it, while Andrei Linde said he would bet his own life. As for me, I
have
just enough confidence about the multiverse to bet the lives of both
Andrei
Linde and Martin Rees’s dog."
--- Steven Weinberg

Brent

On 11/20/2022 4:28 PM, Bruce Kellett wrote:


On Mon, Nov 21, 2022 at 2:52 AM smitra  wrote:


Probability cannot be a fundamental concept in physics as
explained
here:

https://www.youtube.com/watch?v=wfzSE4Hoxbc


I'm afraid Deutsch is a bit too glib in this lecture. He hasn't,
despite his best efforts, removed probability from physics. For
example, in quantum mechanics, he has not explained why, if one
measures the z-spin of a spin-half particle prepared in an
eigenstate of x-spin, one gets only one result -- either z-spin-up
or z-spin-down. If one has eliminated probability, one should be
able to explain which result one gets, and why. It is no solution to
say that with many-worlds, that both results are obtained by
disjoint copies of the experimenter. The experimenter is just one
copy, and one would have to explain the result for each individual
separately. Many worlds does not explain why I, for example, see
only z-spin-up and not z-spin-down. To make sense of that, we need a
viable concept of probability and the Born rule.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit


https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com

[1].


 --
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/ef67fea2-fbf8-6e1a-2b5b-3b5182515732%40gmail.com
[2].


Links:
--
[1]
https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com?utm_medium=emailutm_source=footer
[2]
https://groups.google.com/d/msgid/everything-list/ef67fea2-fbf8-6e1a-2b5b-3b5182515732%40gmail.com?utm_medium=email_source=footer


--
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/e77e1b82b1f376e022d74c9da341a941%40zonnet.nl.

Re: Physics Without Probability

On 21-11-2022 01:28, Bruce Kellett wrote:

On Mon, Nov 21, 2022 at 2:52 AM smitra wrote:

Probability cannot be a fundamental concept in physics as explained
here:

https://www.youtube.com/watch?v=wfzSE4Hoxbc

I'm afraid Deutsch is a bit too glib in this lecture. He hasn't,
despite his best efforts, removed probability from physics. For
example, in quantum mechanics, he has not explained why, if one
measures the z-spin of a spin-half particle prepared in an eigenstate
of x-spin, one gets only one result -- either z-spin-up or
z-spin-down. If one has eliminated probability, one should be able to
explain which result one gets, and why. It is no solution to say that
with many-worlds, that both results are obtained by disjoint copies of
the experimenter. The experimenter is just one copy, and one would
have to explain the result for each individual separately. Many worlds
does not explain why I, for example, see only z-spin-up and not
z-spin-down. To make sense of that, we need a viable concept of
probability and the Born rule.

Bruce

He has argued that fundamental physics cannot be based on probability,
it can at best play a role in an effective description of the physical
world. This excerpt is the most to the point:

https://www.youtube.com/watch?v=wfzSE4Hoxbc=1036s

He then goes on to argue that there is no need to refer to probabilities
in QM using a decision theoretic argument that does not refer to any
notion of a probability.

Saibal

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 11:35 AM Brent Meeker  wrote:

> On 11/21/2022 4:33 PM, Bruce Kellett wrote:
>
> On Tue, Nov 22, 2022 at 11:08 AM Brent Meeker 
> wrote:
>
>> He's wrong that frequentism does not empirically support probability
>> statements.  He goes off on a tangent by referring to "other gamblers".
>> Nothing in physics is certain, yet Deutsch takes a bunch of definite
>> assertions and claims they alone are the real physics.
>>
>
> His critique of frequentism is just a recap of arguments that are well
> known -- you cannot ground probability theory in frequentism, or the idea
> that probabilities are nothing more than ratios of long-run frequencies.
> Long-run frequencies might approximate the probabilities, but they cannot
> be used to ground probability theory -- for well known reasons. I agree
> that he goes off on a number of irrelevant tangents, and he is wrong to
> suppose that frequentism is a main-stream theory of probability (at least,
> these days).
>
>
> But frequencies are how we test probabilistic theories.
>

Testing is not a theoretical grounding of the theory.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLTNVrzp0JRzjwLU_2qb6nosugcSoGYuhtt%3D3Edq9dLOFQ%40mail.gmail.com.

Re: Physics Without Probability

On 11/21/2022 4:33 PM, Bruce Kellett wrote:
On Tue, Nov 22, 2022 at 11:08 AM Brent Meeker
wrote:

He's wrong that frequentism does not empirically support
probability statements. He goes off on a tangent by referring to
"other gamblers". Nothing in physics is certain, yet Deutsch
takes a bunch of definite assertions and claims they alone are the
real physics.

His critique of frequentism is just a recap of arguments that are well
known -- you cannot ground probability theory in frequentism, or the
idea that probabilities are nothing more than ratios of long-run
frequencies. Long-run frequencies might approximate the probabilities,
but they cannot be used to ground probability theory -- for well known
reasons. I agree that he goes off on a number of irrelevant tangents,
and he is wrong to suppose that frequentism is a main-stream theory of
probability (at least, these days).

But frequencies are how we test probabilistic theories.

Brent

Bruce

On 11/20/2022 4:28 PM, Bruce Kellett wrote:

On Mon, Nov 21, 2022 at 2:52 AM smitra wrote:

Probability cannot be a fundamental concept in physics as
explained
here:

https://www.youtube.com/watch?v=wfzSE4Hoxbc

I'm afraid Deutsch is a bit too glib in this lecture. He hasn't,
despite his best efforts, removed probability from physics. For
example, in quantum mechanics, he has not explained why, if one
measures the z-spin of a spin-half particle prepared in an
eigenstate of x-spin, one gets only one result -- either
z-spin-up or z-spin-down. If one has eliminated probability, one
should be able to explain which result one gets, and why. It is
no solution to say that with many-worlds, that both results are
obtained by disjoint copies of the experimenter. The experimenter
is just one copy, and one would have to explain the result for
each individual separately. Many worlds does not explain why I,
for example, see only z-spin-up and not z-spin-down. To make
sense of that, we need a viable concept of probability and the
Born rule.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/everything-list/CAFxXSLQgSxrbySZNq-1HOFOu_7aie5y3Av3bMcYvB0Gp7hyBHg%40mail.gmail.com
<https://groups.google.com/d/msgid/everything-list/CAFxXSLQgSxrbySZNq-1HOFOu_7aie5y3Av3bMcYvB0Gp7hyBHg%40mail.gmail.com?utm_medium=email_source=footer>.

Re: Physics Without Probability

On Tue, Nov 22, 2022 at 11:08 AM Brent Meeker  wrote:

> He's wrong that frequentism does not empirically support probability
> statements.  He goes off on a tangent by referring to "other gamblers".
> Nothing in physics is certain, yet Deutsch takes a bunch of definite
> assertions and claims they alone are the real physics.
>

His critique of frequentism is just a recap of arguments that are well
known -- you cannot ground probability theory in frequentism, or the idea
that probabilities are nothing more than ratios of long-run frequencies.
Long-run frequencies might approximate the probabilities, but they cannot
be used to ground probability theory -- for well known reasons. I agree
that he goes off on a number of irrelevant tangents, and he is wrong to
suppose that frequentism is a main-stream theory of probability (at least,
these days).

Bruce

On 11/20/2022 4:28 PM, Bruce Kellett wrote:
>
> On Mon, Nov 21, 2022 at 2:52 AM smitra  wrote:
>
>> Probability cannot be a fundamental concept in physics as explained
>> here:
>>
>> https://www.youtube.com/watch?v=wfzSE4Hoxbc
>
>
> I'm afraid Deutsch is a bit too glib in this lecture. He hasn't, despite
> his best efforts, removed probability from physics. For example, in quantum
> mechanics, he has not explained why, if one measures the z-spin of a
> spin-half particle prepared in an eigenstate of x-spin, one gets only one
> result -- either z-spin-up or z-spin-down. If one has eliminated
> probability, one should be able to explain which result one gets, and why.
> It is no solution to say that with many-worlds, that both results are
> obtained by disjoint copies of the experimenter. The experimenter is just
> one copy, and one would have to explain the result for each individual
> separately. Many worlds does not explain why I, for example, see only
> z-spin-up and not z-spin-down. To make sense of that, we need a viable
> concept of probability and the Born rule.
>
> 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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/everything-list/CAFxXSLQgSxrbySZNq-1HOFOu_7aie5y3Av3bMcYvB0Gp7hyBHg%40mail.gmail.com.

Re: Physics Without Probability

He's wrong that frequentism does not empirically support probability
statements. He goes off on a tangent by referring to "other gamblers".
Nothing in physics is certain, yet Deutsch takes a bunch of definite
assertions and claims they alone are the real physics.

"The race is not always to the swift, nor the battle to the strong, but
that's the way to bet."

--- Damon Runyan

"In the Austin airport on the way to this meeting I noticed for sale
the October issue of a magazine called Astronomy, having on the cover the
headline “Why You Live in Multiple Universes.” Inside I found a report of
a discussion at a conference at Stanford, at which Martin Rees said that
he was sufficiently confident about the multiverse to bet his dog’s life on
it, while Andrei Linde said he would bet his own life. As for me, I have
just enough confidence about the multiverse to bet the lives of both Andrei
Linde and Martin Rees’s dog."
--- Steven Weinberg

Brent

On 11/20/2022 4:28 PM, Bruce Kellett wrote:

On Mon, Nov 21, 2022 at 2:52 AM smitra wrote:

Probability cannot be a fundamental concept in physics as explained
here:

https://www.youtube.com/watch?v=wfzSE4Hoxbc

I'm afraid Deutsch is a bit too glib in this lecture. He hasn't,
despite his best efforts, removed probability from physics. For
example, in quantum mechanics, he has not explained why, if one
measures the z-spin of a spin-half particle prepared in an eigenstate
of x-spin, one gets only one result -- either z-spin-up or
z-spin-down. If one has eliminated probability, one should be able to
explain which result one gets, and why. It is no solution to say that
with many-worlds, that both results are obtained by disjoint copies of
the experimenter. The experimenter is just one copy, and one would
have to explain the result for each individual separately. Many worlds
does not explain why I, for example, see only z-spin-up and not
z-spin-down. To make sense of that, we need a viable concept of
probability and the Born rule.

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 everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com
<https://groups.google.com/d/msgid/everything-list/CAFxXSLQR4F3uEXO3HCPysF5Rwwr5x6NCOVZ5vk5wmiqu%2BWi8qw%40mail.gmail.com?utm_medium=email_source=footer>.

Re: Physics Without Probability

On 11/21/2022 3:33 AM, John Clark wrote:
On Sun, Nov 20, 2022 at 7:29 PM Bruce Kellett
wrote:

/> The experimenter is just one copy/

And that pinpoints the error in your logic right there.

/> Many worlds does not explain why I, for example, see only
z-spin-up and not z-spin-down. To make sense of that, we need a
viable concept of probability and the Born rule./

Gleason's theorem proved mathematically that if you want this thing
called "probability" to have the property that it is always positive
and never negative, and the property that if you add up all the
"probabilities" they always add up to exactly 100% , then the Born
Rule can be derived from quantum mechanics provided you make the
assumption of non-reality (sometimes called Quantum contextuality),
that is to say if you assume that an unmeasured quality does NOT have
one and only one value. Many Worlds does make that assumption, or
rather it makes the assumption that Schrodinger's equation means what
it says, and once you do that you have no choice but to accept
non-reality. You can still save reality but to do so you must make
additional assumptions (such as the assumption that Schrodinger's
equation does NOT mean what it says), that's why some call Many Worlds
bare bones, no nonsense quantum mechanics, it has no silly bells and
whistles cluttering things up. And that's the sort of thing William of
Ockham would approve of.

It has an infinite number of other worlds, most differing from this
world only in unobservable ways. In comparison, taking the Born rule to
mean what it says seems like modest addition to the theory.

Brent

I admit that does not prove Many Worlds is correct but at least it
passes its first test, and it proves that conventional everyday
assumptions about the nature of reality must be dead wrong; you're
never going to find a quantum interpretation that feels obvious and
intuitively true and is also consistent with experimental
observations. So if Many Worlds is incorrect then something even
stranger must be true.

/> Many worlds does not explain why I, for example, see only
z-spin-up and not z-spin-down./

And Bruce Kellett does not explain what exactly the personal pronoun
"I" means in the context of Many Worlds. In Many Worlds for every
state that the laws of physics allows a particle to be in there is a
Bruce Kellett observing that state; so of course Mr. I will observe
one and only one state.

John K Clark See what's on my new list at Extropolis
<https://groups.google.com/g/extropolis>

trb

--
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/CAJPayv3NTXTaa-Od_JTEKvvmwns6cHqYuSuUs4ZQRNdQH%2BsXjw%40mail.gmail.com
<https://groups.google.com/d/msgid/everything-list/CAJPayv3NTXTaa-Od_JTEKvvmwns6cHqYuSuUs4ZQRNdQH%2BsXjw%40mail.gmail.com?utm_medium=email_source=footer>.

Re: Physics Without Probability

2022-11-21 Thread John Clark

On Mon, Nov 21, 2022 at 6:56 AM Bruce Kellett  wrote:

*> And Many worlds assumes a probabilistic interpretation, contradicting
> the argument that Deutsch is making.*
>

Don't be silly, David Deutsch is a professional physicist and knows
perfectly well, better than you or I do I'll bet, that Quantum Mechanics
can only make probabilistic productions.

*> You can't get separate worlds in which different copies of the observer
> see different outcomes without assuming the Born rule.*
>

As I've said before, nobody ever has to assume the Born Rule because
everybody already knows with certainty that it's true, they know it from
experimentation. And experimentation is the boss not theory, it always has
the last word.

*> So that small amplitudes correspond to low probabilities.*
>

Yes, a small amplitude means there are fewer copies of Bruce Kellett similar
enough to "you" to be called Bruce Kellett that observe the electron going
up than number of Bruce Kelletts that observe the electron going down. So
if a bet was made about what Bruce Kellett will probably see the smart
money would bet on the electron going down.

John K ClarkSee what's on my new list at  Extropolis

kss

trb

>

-- 
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/CAJPayv0d2CifTvvgoKRX_jvMWpEb7p_XAWYOLkwWAiRk2YpLcw%40mail.gmail.com.

Re: Physics Without Probability