Physics, Chemistry, and Mathematics

Advances in the investigation of the physical universe we live in.

Re: What do you have in your hologram?

Postby Typhoon » Wed Apr 29, 2015 4:58 am

Azrael wrote:So perhaps no solid confirmation yet.


No experimental confirmation yet, tentative or solid.
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Re: Physics, Chemistry, and Mathematics

Postby Azrael » Wed Apr 29, 2015 7:37 am

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Re: Physics, Chemistry, and Mathematics

Postby Azrael » Thu Apr 30, 2015 8:41 pm

Typhoon wrote:
Azrael wrote:Weak Measurement

Does anyone have an opinion?


Sorry, no. Have not kept up to date in QM measurement theory.

This article casts doubt on the whole concept of weak measurement.
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Re: Physics, Chemistry, and Mathematics

Postby Doc » Thu Apr 30, 2015 11:15 pm

Azrael wrote:
Typhoon wrote:
Azrael wrote:Weak Measurement

Does anyone have an opinion?


Sorry, no. Have not kept up to date in QM measurement theory.

This article casts doubt on the whole concept of weak measurement.


I read a series of books not long ago that were different about physics I noticed that actual PHD's that read them say the guy has a lot of interesting ideas. While people with less Physics education say the guy is a crack pot. But the ideas are interesting. He talks a lot about the quantum world. When I get home I will try to remember to get the link and post it.
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Re: Physics, Chemistry, and Mathematics

Postby Doc » Fri May 01, 2015 6:57 am

Doc wrote:
Azrael wrote:
Typhoon wrote:
Azrael wrote:Weak Measurement

Does anyone have an opinion?


Sorry, no. Have not kept up to date in QM measurement theory.

This article casts doubt on the whole concept of weak measurement.


I read a series of books not long ago that were different about physics I noticed that actual PHD's that read them say the guy has a lot of interesting ideas. While people with less Physics education say the guy is a crack pot. But the ideas are interesting. He talks a lot about the quantum world. When I get home I will try to remember to get the link and post it.


Hidden in plain sight by Andrew Thomas.

http://www.amazon.com/Hidden-Plain-Sigh ... B008ABSSIW

He is very good at explaining quantum mechanics.

About the Author

Andrew Thomas studied physics in the James Clerk Maxwell Building in Edinburgh University, and received his doctorate from Swansea University in 1992. He is the author of the What Is Reality? website (www.whatisreality.co.uk), one of the most popular websites dealing with questions of the fundamentals of physics. It has been called “The best online introduction to quantum theory”.


The above site seems to have been moved to here:

http://www.ipod.org.uk/reality/
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sat May 02, 2015 11:02 am

Doc wrote:The above site seems to have been moved to here:

http://www.ipod.org.uk/reality/


Thanks for the tip, something to read into. Very clear writing!

His book on Amazon Hidden In Plain Sight: The simple link between relativity and quantum mechanics It is not too expensive, in Kindle version; 1 dollar. 8-) (I believe the truth is always cheap.. only lies are costly and need marketing)
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sat May 02, 2015 11:52 am

Hate to piss on a parade, especially one about physics, but

His [Andrew Thomas] website really does not tell me much. Has he published his ideas in peer-reviewed publications? If so, please provide a link and I shall be happy to look through his paper. The fact that nothing comes up when you search for him on Google is certainly not a good sign. Also, apparently he obtained some form of science degree from the University of Swansea in the UK, but I could not find his name anywhere on the university's site or online paper repository, not even a dissertation under his name. That's another bad sign.

Generally speaking, if someone was to come up with a model to unify QM and GR which is worth serious scientific consideration, then chances are his name would be a lot more prominent in theoretical physics circles. This does not appear to be the case here. [Mod: British style understatement here.]

Judging by the information available to me at this point in time, this is not something I would teach my grandchildren as scientific fact. But that's just a personal opinion now.


I gave it a very brief look. I am not impressed. Moreover, anyone who it talking about unification of gravity and quantum theory is either very speculative or just does not know what he is talking about. This is the foremost problem in theoretical physics, and no one has really made a dent in it in the sense of having a well-defined and mathematically consistent theory or making new testable predictions. There is more hype out there on this subject then on all other aspects of physics combined.

My general recommendation for popularizations is to read only select samples that were written by the cream of the cream -- Feynman, Weinberg, Penrose (be careful some of his stuff is excellent and some of it is pretty far out there. The Road to Reality is exceptionally good), Wheeler, 'tHooft and the earlier books of Hawking (a Brief History of Time in particular). There is a lot of stuff out there written by people, even physics Ph.D.s who don't thoroughly understand what they are talking about and write books for notoriety and money, and say the most outrageous things. Michu Kaku is at the top of my list in that regard, but there are several others. Brian Cox is in the number two slot followed by Susskind (his popularizations are nonsense even if some of his serious physics is quite good). This guy could make the list if a deeper reading reinforces my first impression.


Division by Zero

Now, to contribute something positive, this is what one needs to know and understand:

Gerard t'Hooft | How to become a good theoretical physicist

Proclus later retells a story that, when Ptolemy I asked if there was a shorter path to learning geometry than Euclid's Elements,
"Euclid replied there is no royal road to geometry."
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sat May 02, 2015 12:28 pm

Parodite wrote:
Doc wrote:The above site seems to have been moved to here:

http://www.ipod.org.uk/reality/


Thanks for the tip, something to read into. Very clear writing!

His book on Amazon Hidden In Plain Sight: The simple link between relativity and quantum mechanics It is not too expensive, in Kindle version; 1 dollar. 8-) (I believe the truth is always cheap.. only lies are costly and need marketing)


Not always. Physics [and other science] texts and monographs tend to be expensive due to a limited audience.

I'm thinking of buying this book . . .

http://www.amazon.co.jp/Scaling-Cambrid ... barenblatt

USD $173 for a hardcopy version. About USD $1 per page. Kindle version is about USD $47. Ouch.
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sat May 02, 2015 12:33 pm

I would philosophically guesstimate that the unification of classical physics and quantum physics can be found in the once signature text of Typhoon:

That past is history, the future a mystery, the present is now.

"The past" represents measurements as done in classical physics. Classical physics can predict the past.. but not the present.

"The future" represents the probabilistic nature of quantum phsyics.

Both past and future meet "now" which is where the party occurs, so it seems to me you would need a new/extended physics of "now" in which both the past and future are non-existent.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sat May 02, 2015 12:41 pm

Unfortunately, physics cannot be simplified to a slogan. The devil is very much in the details.
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sat May 02, 2015 12:51 pm

Typhoon wrote:Unfortunately, physics cannot be simplified to a slogan. The devil is very much in the details.


The devil can be in the details.. or in the elephant in the room. The now is a pretty big elephant.

Quick google: The Physics of ‘Now’

For now.. enough to be puzzled about.
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sat May 02, 2015 1:17 pm

Will add that what strikes me as the result of a general tunnel vision problem among specialists, it seems to me one cannot approach the problem of "past, present and future" without also delving into the human brain, neuro-psychology etc. Given that the experience and percepts of past-present-future (4D spacetime) arise in human brain.. one would expect it to be of equal interest as bare bone classical and quantum physics.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sat May 02, 2015 2:06 pm

Parodite wrote:
Typhoon wrote:Unfortunately, physics cannot be simplified to a slogan. The devil is very much in the details.


The devil can be in the details.. or in the elephant in the room. The now is a pretty big elephant.

Quick google: The Physics of ‘Now’

For now.. enough to be puzzled about.


So is this paper correct or not?
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sat May 02, 2015 3:37 pm

Typhoon wrote:
Parodite wrote:
Typhoon wrote:Unfortunately, physics cannot be simplified to a slogan. The devil is very much in the details.


The devil can be in the details.. or in the elephant in the room. The now is a pretty big elephant.

Quick google: The Physics of ‘Now’

For now.. enough to be puzzled about.


So is this paper correct or not?


No idea.. didn't read much of it. You have an idea? Just googled wondering if people have been thinking about a physics of "now". Seems to be the case. Interesting.

Look, of course peer reviewed and ultimately tested theories are the last stages of scientific discovery. People who blog/write their ideas itself is not a problem it seems to me. Playing with ideas, possibilities. The big minds did the same.

What surprises me though is that, if I remember correctly you posted once something on it, a majority of established physicists believe that the many worlds theory is closest to reality. It is in the same realm of other playful ideas.. but seems total bullocks to me though. ;)
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Re: Physics, Chemistry, and Mathematics

Postby Doc » Sat May 02, 2015 6:36 pm

My point in posting Thomas' book is that he is very good at explaining quantum measurement.

Particularly in terms of coherence vs dis-coherence. Which is hardly controversial.
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Re: Physics, Chemistry, and Mathematics

Postby Doc » Sat May 02, 2015 6:40 pm

Typhoon wrote:
Parodite wrote:
Doc wrote:The above site seems to have been moved to here:

http://www.ipod.org.uk/reality/


Thanks for the tip, something to read into. Very clear writing!

His book on Amazon Hidden In Plain Sight: The simple link between relativity and quantum mechanics It is not too expensive, in Kindle version; 1 dollar. 8-) (I believe the truth is always cheap.. only lies are costly and need marketing)


Not always. Physics [and other science] texts and monographs tend to be expensive due to a limited audience.

I'm thinking of buying this book . . .

http://www.amazon.co.jp/Scaling-Cambrid ... barenblatt

USD $173 for a hardcopy version. About USD $1 per page. Kindle version is about USD $47. Ouch.


Ouch indeed.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sat May 02, 2015 10:58 pm

Parodite wrote:
Typhoon wrote:
Parodite wrote:
Typhoon wrote:Unfortunately, physics cannot be simplified to a slogan. The devil is very much in the details.


The devil can be in the details.. or in the elephant in the room. The now is a pretty big elephant.

Quick google: The Physics of ‘Now’

For now.. enough to be puzzled about.


So is this paper correct or not?


No idea.. didn't read much of it. You have an idea? Just googled wondering if people have been thinking about a physics of "now". Seems to be the case. Interesting.

Look, of course peer reviewed and ultimately tested theories are the last stages of scientific discovery. People who blog/write their ideas itself is not a problem it seems to me. Playing with ideas, possibilities. The big minds did the same.

What surprises me though is that, if I remember correctly you posted once something on it, a majority of established physicists believe that the many worlds theory is closest to reality. It is in the same realm of other playful ideas.. but seems total bullocks to me though. ;)


While consensus of opinion or lack thereof is not basis for deciding issues in physics,
most physicists do not subscribe to the many-worlds hypothesis but to the standard Born interpretation.

As far as I'm aware, the many world hypothesis is not testable and thus falsifiable.

There is a vocal minority that promotes it.
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sun May 03, 2015 9:34 am

Typhoon wrote:While consensus of opinion or lack thereof is not basis for deciding issues in physics,
most physicists do not subscribe to the many-worlds hypothesis but to the standard Born interpretation.


Didn't know there was a standard Born interpretation.. just the standard application of the Born rule.. which indeed rules as always.

As far as I'm aware, the many world hypothesis is not testable and thus falsifiable.

There is a vocal minority that promotes it.


Ok.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sun May 03, 2015 2:16 pm

Parodite wrote:
Typhoon wrote:While consensus of opinion or lack thereof is not basis for deciding issues in physics,
most physicists do not subscribe to the many-worlds hypothesis but to the standard Born interpretation.


Didn't know there was a standard Born interpretation.. just the standard application of the Born rule.. which indeed rules as always.



The key point is the Schroedinger equation describes the time evolution of the complex valued [wave] function: Psi(x,y,z,t)

The question at the time was what does Psi actually correspond to?

Born's insight was that Psi(x,y,z,t) corresponds to a complex probability amplitude and that the probability density
is given by Psi* Psi where Psi* is the complex conjugate. In the case of a single particle, the probability of finding it in an infinitesimal volume
dV = dxdydz at times t is given by Psi* Psi dV.

This is part of Born's interpretation/rule/law or whatever one may wish to call it, but it's Born's.
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Sun May 03, 2015 4:11 pm

Typhoon wrote:
Parodite wrote:
Typhoon wrote:While consensus of opinion or lack thereof is not basis for deciding issues in physics,
most physicists do not subscribe to the many-worlds hypothesis but to the standard Born interpretation.


Didn't know there was a standard Born interpretation.. just the standard application of the Born rule.. which indeed rules as always.



The key point is the Schroedinger equation describes the time evolution of the complex valued [wave] function: Psi(x,y,z,t)

The question at the time was what does Psi actually correspond to?

Born's insight was that Psi(x,y,z,t) corresponds to a complex probability amplitude and that the probability density
is given by Psi* Psi where Psi* is the complex conjugate. In the case of a single particle, the probability of finding it in an infinitesimal volume
dV = dxdydz at times t is given by Psi* Psi dV.

This is part of Born's interpretation/rule/law or whatever one may wish to call it, but it's Born's.


What interests me is if the wave function, as a mathematical formalism of calculating the probability of outcomes, describes all elements of the physical reality contained in the experimental setup.. or not. Old discussion.. I know. Hidden variables etc. Niels Bohr and Einstein did not resolve it after decades of discussion and Richard Feynman discourages people to even try it lest one ends up crazy at the end of the road.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Sun May 03, 2015 4:36 pm

Parodite wrote:
Typhoon wrote:
Parodite wrote:
Typhoon wrote:While consensus of opinion or lack thereof is not basis for deciding issues in physics,
most physicists do not subscribe to the many-worlds hypothesis but to the standard Born interpretation.


Didn't know there was a standard Born interpretation.. just the standard application of the Born rule.. which indeed rules as always.



The key point is the Schroedinger equation describes the time evolution of the complex valued [wave] function: Psi(x,y,z,t)

The question at the time was what does Psi actually correspond to?

Born's insight was that Psi(x,y,z,t) corresponds to a complex probability amplitude and that the probability density
is given by Psi* Psi where Psi* is the complex conjugate. In the case of a single particle, the probability of finding it in an infinitesimal volume
dV = dxdydz at times t is given by Psi* Psi dV.

This is part of Born's interpretation/rule/law or whatever one may wish to call it, but it's Born's.


What interests me is if the wave function, as a mathematical formalism of calculating the probability of outcomes, describes all elements of the physical reality contained in the experimental setup.. or not. Old discussion.. I know. Hidden variables etc. Niels Bohr and Einstein did not resolve it after decades of discussion and Richard Feynman discourages people to even try it lest one ends up crazy at the end of the road.


All evidence points to nature being best described by QM.

If some people are uncomfortable with this, then in my view, it's their problem and they're welcome to spend their time looking for hidden classical gears and levers.

As for me, I think that there are many far far more interesting open questions in fundamental physics such as:

* the existence of the mass gap in non-Abelian QFT?

* dark matter and energy or not?

* any physics beyond the SM?
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Re: Physics, Chemistry, and Mathematics

Postby Parodite » Mon May 04, 2015 9:40 am

Typhoon wrote:
Parodite wrote:What interests me is if the wave function, as a mathematical formalism of calculating the probability of outcomes, describes all elements of the physical reality contained in the experimental setup.. or not. Old discussion.. I know. Hidden variables etc. Niels Bohr and Einstein did not resolve it after decades of discussion and Richard Feynman discourages people to even try it lest one ends up crazy at the end of the road.


All evidence points to nature being best described by QM.

If some people are uncomfortable with this, then in my view, it's their problem and they're welcome to spend their time looking for hidden classical gears and levers.


I'll just think out loud a bit, not to bore you on purpose though. ;)

"Classical gears and levers" are physical objects/systems better be taken very seriously.. simply because they are real. The gearbox of my car is doing fine and behaves rather predictable. One can also look at the moon without interfering with it much.. which is why such a macro scale object behaves predictable when somebody on earth looks at it through a telescope. Caveat: classical predictability is not absolute and perfectly total: it concerns approximations within a limited domain of validity. There is a "classical limit".

On the subatomic level in a QM measurement setup, where the extremely small "object under observation" (very small regions of spacetime) meets the equally small measuring device's "sensor point".. indeed it is a different ball game. Here, in the micro cosmos of QM, randomness interacts with randomness and other weird things happen. No classical predictions are possible and what happens turns out to be only possible to describe using a mathematical formalism that gives the likelihood of outcomes. This made Einstein and others very uneasy... because a theory that can only produce likelihoods must be incomplete. His "God doesn't play dice" argument; some hidden variables were thought to be necessary to fill the gap. But most physicists have abandoned the idea that hidden variables are needed to explain anything in the micro cosmos of QM.

It occurs to me that a much better way to solve the hidden variable controversy once and for all, is to say that QM revealed hidden variables in classical physics. So it is the other way round in fact. This is not just a semantic trick: it IMO better fits the facts. Subatomic processes are "hidden" (invisible to the classical observing eye) in larger scale objects... but are nevertheless there. So the Born rule itself is the "hidden variable" that operates in the larger scales of classical physics, as it explains why classical physics can only be accurate within a limited domain and why Heisenberg's uncertainty principle always kicks in at some point. So there are no hidden variables missing in/beyond QM theory.. QM revealed hidden variables that were missing in classical physics. QM is the hidden variable of Classical physics.

If the above is sensible, then the only valid question that remains is how to recover classical physics from QM...and vice-versa.
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Re: Physics, Chemistry, and Mathematics

Postby Doc » Mon May 04, 2015 11:44 pm

OK CS Here is what Thomas has to say about measurement. Do you have any problems with it?(I transcribed this so any typos are mine)

Let us reconsider a particle which is isolated from the rest of the universe, or has been generated as a new particle and has not yet interacted with the rest of the universe, ie., it has not yet been measured or observed. What can we say about its properties? Once again in the absence of absolutes(There is not universal unit of measure that it absolute - my insert), nature is fundamentally unable to assign absolute values to the particle. And because the particle has not yet interacted with the rest of the universe to be measured or observed, nature is unable to assign any relative values either. As discussed in the last section, all we can say about its property values is "They go up to 11", an essentially meaningless statement reflecting the fact that the particle's property values are undefined -- they have no relation to the rest of the universe. Before observation or measurement, the object must be like a blank sheet: it must be an undefined object with the potential to take up any possible property values. So before observation, the object must have a multi-valued form of reality -- as is observed in quantum mechanical behavior. It is only when the object interacts with the rest of the universe that its properties become progressively tied down to particular values.

This is what we saw in the case of environmental decoherence. It is through interaction with the rest of the universe, via the measuring apparatus,(the measuring apparatus being huge compared to the particle measured -- my insert) that the properties of a particle become fixed.

So here, rather wonderfully, we have a rational -- an explanation -- for the multi-valued nature of quantum behavior before measurement, or observation. Here are the logical steps we followed to get to this conclusion:

1) Nature has no access to absolutes, so it is always fundamentally unable to assign absolute property values to a particle.

2)Therefore, particle properties are defined by the relationship of that particle with the rest of the universe.

3)Bearing this in mind, if we consider as isolated particle, or a newly generated particle which has not yet been measured or observed, nature has fundamentally no way of assigning any form of property values -- absolute or relative to the particle.

4) The properties of the particle are therefore fundamentally undefined -- like a blank sheet. Its properties must have the potential to be any possible value

5)The object must therefore have a multi-valued form of reality before it is observed. It is only after observation -- when the object interacts with the rest of the universe -- that the properties of the object become fixed.



Anyway what do you think about this?
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Tue May 05, 2015 12:14 pm

Doc wrote:OK CS Here is what Thomas has to say about measurement. Do you have any problems with it?(I transcribed this so any typos are mine)

Let us reconsider a particle which is isolated from the rest of the universe, or has been generated as a new particle and has not yet interacted with the rest of the universe, ie., it has not yet been measured or observed. What can we say about its properties? Once again in the absence of absolutes(There is not universal unit of measure that it absolute - my insert), nature is fundamentally unable to assign absolute values to the particle. And because the particle has not yet interacted with the rest of the universe to be measured or observed, nature is unable to assign any relative values either. As discussed in the last section, all we can say about its property values is "They go up to 11", an essentially meaningless statement reflecting the fact that the particle's property values are undefined -- they have no relation to the rest of the universe. Before observation or measurement, the object must be like a blank sheet: it must be an undefined object with the potential to take up any possible property values. So before observation, the object must have a multi-valued form of reality -- as is observed in quantum mechanical behavior. It is only when the object interacts with the rest of the universe that its properties become progressively tied down to particular values.

This is what we saw in the case of environmental decoherence. It is through interaction with the rest of the universe, via the measuring apparatus,(the measuring apparatus being huge compared to the particle measured -- my insert) that the properties of a particle become fixed.

So here, rather wonderfully, we have a rational -- an explanation -- for the multi-valued nature of quantum behavior before measurement, or observation. Here are the logical steps we followed to get to this conclusion:

1) Nature has no access to absolutes, so it is always fundamentally unable to assign absolute property values to a particle.

2)Therefore, particle properties are defined by the relationship of that particle with the rest of the universe.

3)Bearing this in mind, if we consider as isolated particle, or a newly generated particle which has not yet been measured or observed, nature has fundamentally no way of assigning any form of property values -- absolute or relative to the particle.

4) The properties of the particle are therefore fundamentally undefined -- like a blank sheet. Its properties must have the potential to be any possible value

5)The object must therefore have a multi-valued form of reality before it is observed. It is only after observation -- when the object interacts with the rest of the universe -- that the properties of the object become fixed.



Anyway what do you think about this?


Not even wrong.

Let's have a look at the non-relativistic QM Schrödinger equation which is known to describe the evolution of, for example, a single partice wave function Psi:

Image

m is the mass of the particle. It is not ever "undefined".
Even if we set the potential V(x), which in the QM case describes the interaction of the particle with the rest of the universe, identically to zero
m is still defined.

The relativistic QM Dirac equation for a single particle, with V(x) zero, is given by

Image

wherein the particle now has both mass m and the matrices beta, alpha_1, alpha_2, alpha_3 which describe the electron's intrinsic spin of 1/2 [in units of hbar: Planck's constant / 2 * Pi]

These properties carry over into the QFT of the electron:

Image

[click on the equation for the link to the details]

To sum up, if the properties of a fundamental particle, it's mass, intrinsic spin, and possible charges (electric, weak, colour) are "undefined" at some point, then we can't write down an equation for it.

Another point: mathematics is the language of the physical universe.
I don't think that one can learn physics without mathematics.

For anyone who would like to learn non-relativistic QM, the best textbooks are

Quantum Mechanics: Vol. I and II by Claude Cohen-Tannoudji and Bernard Diu

bar none.
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Re: Physics, Chemistry, and Mathematics

Postby Typhoon » Tue May 05, 2015 12:35 pm

Parodite wrote:
Typhoon wrote:
Parodite wrote:What interests me is if the wave function, as a mathematical formalism of calculating the probability of outcomes, describes all elements of the physical reality contained in the experimental setup.. or not. Old discussion.. I know. Hidden variables etc. Niels Bohr and Einstein did not resolve it after decades of discussion and Richard Feynman discourages people to even try it lest one ends up crazy at the end of the road.


All evidence points to nature being best described by QM.

If some people are uncomfortable with this, then in my view, it's their problem and they're welcome to spend their time looking for hidden classical gears and levers.


I'll just think out loud a bit, not to bore you on purpose though. ;)

"Classical gears and levers" are physical objects/systems better be taken very seriously.. simply because they are real. The gearbox of my car is doing fine and behaves rather predictable. One can also look at the moon without interfering with it much.. which is why such a macro scale object behaves predictable when somebody on earth looks at it through a telescope. Caveat: classical predictability is not absolute and perfectly total: it concerns approximations within a limited domain of validity. There is a "classical limit".

On the subatomic level in a QM measurement setup, where the extremely small "object under observation" (very small regions of spacetime) meets the equally small measuring device's "sensor point".. indeed it is a different ball game. Here, in the micro cosmos of QM, randomness interacts with randomness and other weird things happen. No classical predictions are possible and what happens turns out to be only possible to describe using a mathematical formalism that gives the likelihood of outcomes. This made Einstein and others very uneasy... because a theory that can only produce likelihoods must be incomplete. His "God doesn't play dice" argument; some hidden variables were thought to be necessary to fill the gap. But most physicists have abandoned the idea that hidden variables are needed to explain anything in the micro cosmos of QM.

It occurs to me that a much better way to solve the hidden variable controversy once and for all, is to say that QM revealed hidden variables in classical physics. So it is the other way round in fact. This is not just a semantic trick: it IMO better fits the facts. Subatomic processes are "hidden" (invisible to the classical observing eye) in larger scale objects... but are nevertheless there. So the Born rule itself is the "hidden variable" that operates in the larger scales of classical physics, as it explains why classical physics can only be accurate within a limited domain and why Heisenberg's uncertainty principle always kicks in at some point. So there are no hidden variables missing in/beyond QM theory.. QM revealed hidden variables that were missing in classical physics. QM is the hidden variable of Classical physics.

If the above is sensible, then the only valid question that remains is how to recover classical physics from QM...and vice-versa.


Bell's Theorem does the job.
All the world's a stage.
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