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Maxwell's equations and determinism

by vidmar
Tags: determinism, equations, maxwell
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CJames
#19
Sep8-05, 04:01 PM
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P: 355
I'm lost. The motion of the planets is indeed observable, in principle and in reality, and has been for a great deal of time.
Crosson
#20
Sep8-05, 06:11 PM
P: 1,295
I'm lost. The motion of the planets is indeed observable, in principle and in reality, and has been for a great deal of time.
Think harder. The picture I showed you is a cartoon. This is important because you will not find a photograph of the solar system from that perspective. The cartoon is a theoretical model, it is impossible (in principle, considering optics) to actually observe the exact scene that that cartoon depicts. Yet the predictions of the model are correct, and we accept the existence of orbits as a fact even though no has ever observed them as depicted in that cartoon.

The point is that we can infer the existence of things that we don't see, if it makes our world view more conceptually pleasant.
Juan R.
#21
Sep9-05, 06:20 AM
P: 416
Quote Quote by vidmar
OK I might as well add some of my own thoughts.
First of all, when I say I like determinism, it does not mean that I don't find theories, which are based on probabilities and are said to be undeterministic, interesting and useful if not beautiful. I just mean that I would prefer a theory at least in principle to allow for only one evolution of an observed system (even if the underlying technical difficulties don't enable us to have closed formed solutions - as for example in the three body problem of Newton - there the movement is determined (except for singularities) even though we can't have closed formed solutions as in the two body case). QM on the other hand is inherently undterministic (as far as I know) in the sense that gievn a system, its future development is not determined.
I also don't think that scientific experiments (can) prove (even if only in the limited strict scientific sense) that the world is undeterministic. What they show is that on a certain level of precision of physical measurments we have theories, which equipt us with tools necessary for the calculations of certin probabilities, that agree with the observed data within the error of measurment. But that doesn't mean that the world need be inherently undeterministic, let alone that we cannot have a deterministic theory, which would describe it. This may easily be seen with the introduction of hidden variables (which in my view don't make the theory incomplete). The succesfullness of a theory in physics may be measured only by its ability to predict the results of measurments and not by a formalism one chooses to have for it. The latter is more a matter of taste (as long as it does not entail that the theory would become less predicitve or make it harder to produce results) as it is a consequence of the world around us.
The problem is that for explaining experimental data one needs formulations with deterministic forces more random forces. Determinism is a phylosophical attitude and i, of course, respect if you like it, but is scientifically unproven. In fact, none even conceivable experiment can prove determinism. Of course, is a phylosophical option.

In classical physics, systems are not deterministic: e.g. thermodynamics or chemical kinetics.

Yes, experiments can prove that the world is undeterministic by measuring random forces, which cannot be reduced to deterministic forces. From a phylosphical view, it is true that nondeterminism is not proved but scientifically it is. You have a random copmponent that cannot be explained in determinisitc terms, that is science. Now you can phylosophically claim that that random component is really caused by an underlying deterministic theory. Yes, phylosophically it is possible. But and scientifically?

If you want your hypotesis to be scientific you may prove that can be verified (falsable) in experiments.

You may formulate the deterministic final EXACT theory, then derivate random components from it and show that coindice with experiments. This is by definition imposible because by definition the theory may be exact (which may be imposible), you may measure with infinite precision, which is imposible, the proposed state of all universe (even beyond observable universe!), which is imposible, and may compute the EXACT result, which is imposible (except by the use of a perfect computer more larger than universe itself), then and only then if experiment coincides with theory you could prove that universe is determinist.

But we compute with imperfect computers, measure with finite precision, develop inexact theories, and cannot know the state of the entire universe. In fact, there is further limitations even for measuring positions and momentum of 1024particles in an ideal gas. Therefore experiments prove that Ftotal = Fdeterm + Frandom

And that is all science can say.

You cannot apeal to hidden variables because if are hidden. How do you scientifically show that variables are there?

It is like the hyphotesis of "pink elephants" that i said.

Personally, I see not problem with the phylosophical interpretation of a world which is non determinist. That mean free will, and love, and ethics, etc.
Juan R.
#22
Sep9-05, 06:33 AM
P: 416
Quote Quote by Crosson
I dare you to look at the following picture of a theoretical model that could NEVER be observed, even in principle, but can only ever be infered INDIRECTLY from routine observations. This model is accepted as a practical fact today:

http://eos.uom.gr/~hatzifot/orbits-trans.gif
I think that you are a bit confounded.

http://uts.cc.utexas.edu/~setreal/Pi...20building.jpg

You are claiming basically that Empire tate does not exist because i cannot see it entire. I am sited at north i only can see a side, if i am at west i can see another side but like i cannot see all togheter it cannot exist. Moreover like i cannot see a guy sited in the floor 25 from the street but i can the guy if i am inside the Emipre, in the 25 (and then cannot see the Empire), them both Empire state and the guy both do not exist.



I cannot see the entire solar system once (in principle I believe that one could) but i can see parts of them at each time and then reconstruct the entire system in a graphical from. Like i can obtain a collection of photos of the Empire and reconstruct it with a graphical package.

Quote Quote by Crosson
Why don't you take a look at the rest of the universe? For thousands of years western astronomers held the doctrine that the heavens were immutable, unchanging. The combined astronomical observations of all the humans who ever lived before the 15th century, considering that Astronomy was as important a skill in those days as driving a car is today, tend to support determinism.
For classical mechanics

a = Fdeterm + Frandom

Random components is related to Temperature and strengh "gamma" of interactions, inverse of mass, etc.

In Astronomy, "gamma" --> 0, and T --> 0, and (1/m) --> 0... and

a --> Fdeterm

But is only an approximation. For example, T is not zero in space, but is so small that effects are not measured in usual astronomical experiments.

The problem of physics is that began with Astronomy and the myth of determinism arised because in astronomy things appears to be deterministic. Chemistry began with condensed matter and newer claimed that world was deterministic. Chemistry always was based in uncertainlty, therein that was did arise like science 100 years after than physics.
Nam_Sapper
#23
Sep9-05, 06:34 AM
P: 26
QM doesn't disprove determinism at least for inanimate objects.
It only proves it is incapable of determining specific causes and making non-statistical predictions for itself.

Bohmian Mechanics is of course an excellent formal interpretation of QM theory. Science is after all based upon causality, not witchcraft, and Bohm succeeded in offering a logically rational interpretation of QM effects, carrying out Einstein's hope. The latest installment, the Transactional Interpretation of QM, is also an extension of Einstein's deterministic and logical program, only this time picking up from Feynman's projected agenda.

Thus:

Einstein --> Bohm --> Feynman --> Cramer --> Mead.

Offering the best and most scientifically cogent interpretation of QM yet conceived. Mead carried off Feynman's hope of formulating QED without using Maxwell's Equations at all! (and he succeeded where Feynman failed)
The final result is Collective Electrodynamics, a short but awesome feat.
Juan R.
#24
Sep9-05, 07:09 AM
P: 416
Quote Quote by Nam_Sapper
QM doesn't disprove determinism at least for inanimate objects.
It only proves it is incapable of determining specific causes and making non-statistical predictions for itself.
False, QM stablishs that classical determinism does not work. In fact, any attempt to introduce determinism on QM is based in hidden variables, doing clear that if pure determinism exists, it cannot be observed, and if cannot be observed then it cannot be proved, doing determinisitc interpretations a field of phylosophy or methaphysics.

In a more thecnical side, still nobody has shown like probabilities of QM arises from an underliyng -phylosophical- deterministic evolution.

Quote Quote by Nam_Sapper
Bohmian Mechanics is of course an excellent formal interpretation of QM theory.
False, this is the reason that is not followed by physicists, except by some guys with a distorted view of reality. Even Bohm claimed that quantum potential is "strange".

The best example of that Bohm mechanics is not complete or consistent is that there is dozens of different versions of it. E.g. Hilley version of Bohm (Broglie/Bohm) emphasizes that quantum potential is the key, whereas the Dürr School (named Bohmian mechanics) regards the guidance condition as the fundamental equation and avoids the quantum potential.

Quote Quote by Nam_Sapper
Science is after all based upon causality, not witchcraft, and Bohm succeeded in offering a logically rational interpretation of QM effects, carrying out Einstein's hope.
False, chemistry (e.g. chemical kinetics) is not deterministic being causal. Statistical mechanics is causal being no determinisitc, Langevin equations are causal being no deterministic, etc.

You are confounding causality with determinism.

Bohm offered a posibility which was studied but is rather discredited today. There is not logical rationality on Bohm theory. In fact, is more "weird" that usual QM claiming for misterious effects that are hidden and cannot be observed (even in principle). The idea that Bohm theory is carrying out Einstein's hope is complete nonsense. Einstein claimed for a complete determinism based in observable reality. Einsten waited reduce QM to classical physics. Einstein said about Bohm mechanics

it was unnecessary superstructure
Bohm claim for a unobserved reality: a new mechanics that is not classical mechanics, is based in hidden variables (therefore is not physical) and obtain less results that from standard approaches.
Crosson
#25
Sep10-05, 03:17 AM
P: 1,295
In fact, is more "weird" that usual QM claiming for misterious effects that are hidden and cannot be observed (even in principle).
How ironic it is that standard QM makes use of "hidden variables" .When is the last time anyone measured a wave function? Wave functions are inobservable in principle and so it is they which are the true hidden variables.

Bohm's theory is much more concrete then standard QM, since it speaks of particles as having trajectories.
inha
#26
Sep10-05, 03:19 AM
P: 576
You really really have to stretch the concept of wave function to call it a hidden variable.
Juan R.
#27
Sep10-05, 08:41 AM
P: 416
Quote Quote by Crosson
How ironic it is that standard QM makes use of "hidden variables" .When is the last time anyone measured a wave function? Wave functions are inobservable in principle and so it is they which are the true hidden variables.

Bohm's theory is much more concrete then standard QM, since it speaks of particles as having trajectories.
I see that you have a very distorted understanding that QM is. I see no need for contining this discussion before you learn QM from a textbook. After we will can continue the discussion.

Of course, Bohm theory is not more concrete than standard QM. This is the reason that is not standard :-)

In fact, it is so "weird" that only a "dozen of" people follows it.

But if you do not understand standard QM, how can you understand Bohm theory?

The trajectories of Bohm theory are not real trajectories like in classical mechanics, therefore the supposed "rationality" is lost.

Moreover, that trajectories are unobserved. Therefore, if existence is purely a philosophical isssssssssssssuuuuuuueeeeee.

That even ignoring that Bohm theory is less useful, consistent, and predictive that standard approach.

Even Einstein -who rejected QM and loved classical physics- rejected Bohm theory

too cheap
Einstein 1952
Crosson
#28
Sep10-05, 03:41 PM
P: 1,295
I see that you have a very distorted understanding that QM is. I see no need for contining this discussion before you learn QM from a textbook. After we will can continue the discussion.
I see that you have reached the lowest common denominator, smearing me as someone who does not even understand the physics we are discussing. I assure you that I have a deep understanding of quantum mechanics. Unlike you, I have textbooks on Bohmian theory in addition to my textbooks on standard QM, so I am interested in the content of the theory rather then as labeling it with the term "hidden variables" in some kind of marketing attempt to brainwash young physicist.

If you were to read a text on Bohm's theory, you will see that nothing about the trajectories makes them "unobservable in principle", that's totally bogus propaghanda. The only thing which indicates that the trajectories are hidden is one of the traditional postulates of QM: that the wavefunction is the most complete possible description of the system.

There is no reason for this, it is postulated. It is just an assumption, and doesn't go anywhere towards proving that Bohmian trajectories are unobservable, QM just assumes there are not.

Lets get even more specific. Another postulate of QM is this voodoo: All observations correspond to self-adjoint operators, and the measured quantities correspond to that operator's spectrum of eigenvalues.

The problem with this is that it is impossible to construct a time operator in standard QM. In the 1950s Pauli proved that the above postulate is what imposes this limitation.

Of course, because Bohm's quantum theory of motion describes particles moving with well defined trajectories, it is relatively straight foward to calculate how much time it takes for various interesting events to occur. It is hoped that one day experimental precision will extend to very short time scales that will allow us to test predictions of Bohm's theory that do not exist in standard QM.

Let me repeat myself: Bohm's theory does not involve anything which could be called a "hidden variable". This is a marketing term used by many physicist who do not want to admit that the complex-valued wave function is what is truly hidden from observation. (What we observe are postions, momenta, energy levels and hopefully one day time scales, we certainly don't measure complex-valued wave functions).
reilly
#29
Sep10-05, 03:51 PM
Sci Advisor
P: 1,082
There's a lot of really weird stuff in this thread. Planetary orbits? Well, just look in your newspaper for the times of "planet-rise" and "planet-set", which seem to correspond to reality. These are, of course based on the standard theory of planetary orbits, with, perhaps some perturbations -- the data can be found in the ephemeris. And, then there's NASAs various probes which seem to get to where they are going. Crosson, if you have a better theory, lay it on us. For planetary orbits, theory and observation agree nicely. What else do you want?

Bohm to the contrary, QM is the best game in town. Further, it's been around for long enough that many physicists have a very good understanding -- for example. lasers, magnetic resonance, optical pumping, and on and on. Bohm has not gotten very far in the physics community because his work, Bohm-Aronof (sp?) as an exception, has not led to any new physics. It's a kluge designed to alleviate philosophical discomfort, rather that confront any empirical situation. It certainly is not Occam friendly.

And remember, whether in Newtonian or Einsteinian form, theory gives no clue as to the why of gravitation; who knows the why of electromagnetic fields? There is not a physics theory around that is anything other than descriptive -- frankly, some folks claim that classical physics is somehow different in interpretive substance than today's physics. Nothing could be further from the truth. If you are pushing nostalgia for the illusory certainty of past theory, why not go back to the idea of prime mover?

Crosson -- of course we can measure wave functions, at least up to a phase. We're talking scattering experiments for example. QM will continue to be the best game in town until it fails to explain an experiment or phenomena that it should be able to explain. That's the way science works.

Regards,
Reilly Atkinson
Crosson
#30
Sep11-05, 01:33 AM
P: 1,295
Crosson -- of course we can measure wave functions, at least up to a phase.
Actually what you measure are positions, energies, momenta. People use wavefunctions to calculate energies, and then measure energies, and the next thing you know they are saying they have measured a wavefunction. All I am saying is that the complex-valued wavefunction is a hidden variable that is used to predict things that we actually measure, where as Bohm's theory always speaks in terms of things we directly measure: postions, energies and statistical Hamilton-Jacobi functions. (How would a wavefunction be measured? With what sort of complex measuring device?)

My point about orbits was obviously a miss. I am not claiming that copernican/ptolemaic (newtonian really) astronomy does not accurately predict the positions of celestial bodies. I was simply saying that the orbits we imagine the planets to move along cannot be directly observed.

Personally I don't give a crap about observation, but if someone attacks the causal (Bohmian) interpretation of QM on the grounds that quantum trajectories are inobservable (the "in principle" part comes from that unfounded assumption of QM that I brought up earlier), then I expect that person to think about which things we discuss in physics are truly observable: the truth is that many are not.

Occam says that one should not increase, beyond what is necessary, the number of entities required to explain anything. Bohm's theory does not "increase the number of entities", it simply talks about a particle and a wave associated with the particle (the wave is a generalized Hamilton's statistical function). QM talks about both these things, but in speaks of the particle in a totally inconsistent nonsensical way (as if it teleports around through places it has "no probability of being").

If the particle and its properties do not exist other then when they are measured, what sort of particle is that? Didn't someone accuse me of claiming the empire state building does not exist when we are not looking at it? How ironic that this is the world view of standard QM which I am against.
Juan R.
#31
Sep11-05, 10:00 AM
P: 416
Quote Quote by Crosson
I see that you have reached the lowest common denominator, smearing me as someone who does not even understand the physics we are discussing. I assure you that I have a deep understanding of quantum mechanics. Unlike you, I have textbooks on Bohmian theory in addition to my textbooks on standard QM, so I am interested in the content of the theory rather then as labeling it with the term "hidden variables" in some kind of marketing attempt to brainwash young physicist.
Simply to say

Quote Quote by Crosson
How ironic it is that standard QM makes use of "hidden variables" .When is the last time anyone measured a wave function? Wave functions are inobservable in principle and so it is they which are the true hidden variables.

Bohm's theory is much more concrete then standard QM, since it speaks of particles as having trajectories.


Quote Quote by Crosson
If you were to read a text on Bohm's theory, you will see that nothing about the trajectories makes them "unobservable in principle", that's totally bogus propaghanda. The only thing which indicates that the trajectories are hidden is one of the traditional postulates of QM: that the wavefunction is the most complete possible description of the system.


Quote Quote by Crosson
There is no reason for this, it is postulated. It is just an assumption, and doesn't go anywhere towards proving that Bohmian trajectories are unobservable,
Quote Quote by Crosson
QM just assumes there are not.
"Just Assumes"

Quote Quote by Crosson
Lets get even more specific. Another postulate of QM is this voodoo: All observations correspond to self-adjoint operators, and the measured quantities correspond to that operator's spectrum of eigenvalues.

The problem with this is that it is impossible to construct a time operator in standard QM. In the 1950s Pauli proved that the above postulate is what imposes this limitation.
QM would be wrong if there was a time operator

You have no idea of time is. Of course Bohm theory is unnecesary (even if were consistent) for obtain a time operator. Strictly a time superoperator.

Quote Quote by Crosson
Of course, because Bohm's quantum theory of motion describes particles moving with well defined trajectories,
Completely false, the trajectories of Bohm are not classical trajectories and are not well defined.

Quote Quote by Crosson
it is relatively straight foward to calculate how much time it takes for various interesting events to occur. It is hoped that one day experimental precision will extend to very short time scales that will allow us to test predictions of Bohm's theory that do not exist in standard QM.
I already cited a very recent experiment where QM offered the correct answer and Bohm theory, again, the wrong answer.

Quote Quote by Crosson
Let me repeat myself: Bohm's theory does not involve anything which could be called a "hidden variable".
Of course false. You do not understand nothing of Bohm theory.

Quote Quote by Crosson
This is a marketing term used by many physicist who do not want to admit that the complex-valued wave function is what is truly hidden from observation. (What we observe are postions, momenta, energy levels and hopefully one day time scales, we certainly don't measure complex-valued wave functions).
Marketing? Is the complex valued function a hidden variable?

But are you studied QM some day? do you know what is the |Phy> in QM? do you know what is a ray?

For you Bohm theory of hidden variables is physical and both QM and planets orbits are hidden variables theories.

Crosson
#32
Sep11-05, 11:58 AM
P: 1,295
This is my last response to you Juan, because you are an internet troll. You responded to my points with various and that is not enough a discussion to be worth my time.

You seem hung up on the idea that I don't understand basic QM, and even after I try to move on beyond that disgusting obstacle to our discussion, you make a cocky remark like "simple to say" and repeat your groundless accusations. I feel totally disrespected by you, I don't feel that you have read or thought about what I have had to say at all. Here is one of your false characterizations of my point:

For you...orbits are hidden variables.
I laugh at this, because if you truly think that that is the point I am making by talking about orbits, then you have failed to understand basic philosophy of science. Given that, I find it hard to believe that you have actually thought about standard or Bohmian QM at all; it is more likely that you simply learned to apply the voodoo rules of standard QM and to spout the party line about Bohmian mechanics. Here is how I feel about you, troll:
Juan R.
#33
Sep12-05, 07:01 AM
P: 416
Quote Quote by Crosson
How ironic it is that standard QM makes use of "hidden variables" .When is the last time anyone measured a wave function? Wave functions are inobservable in principle and so it is they which are the true hidden variables.

Bohm's theory is much more concrete then standard QM, since it speaks of particles as having trajectories.
About planetary orbits you basically said that were unobserved. You waited that we said "oh yes they are unobserved, therefore, unobserved Bohm trajectories are also scientific ones". But, i and others already said on orbits, and fortunately people has studied Bohm theory and this is the reason that is rejected.

About "realism" of Bohm mechanics, it is interesting how you omit reference i cited where Bohm mechanics has been experimentally discredited. It is also interesting like you ignore the rest of my arguments and quotes, including Einstein rejection of it.

In short, Bohm mechanics is

artificial metaphysics
Pauli
Locrian
#34
Sep12-05, 09:39 AM
P: 1,737
Hi Crosson. You posted way back on page one:

Quote Quote by Crosson
The predictive power of QM doesn't prove that the world is indeterminate. Determinism says that given the current universe state, there is one and only one future universe-state.
I had always thought determinism stated that given the current universe state, there is only one future universe-state and it can be found. By found, I mean that with some method - maybe even utilizing tools we can only imagine - the future universe-state can be known.

Any comments on this?
Crosson
#35
Sep12-05, 12:14 PM
P: 1,295
I had always thought determinism stated that given the current universe state, there is only one future universe-state and it can be found. By found, I mean that with some method - maybe even utilizing tools we can only imagine - the future universe-state can be known.
Causal Determinism, as discussed by philosophers and myself, does not require there to be any method to determine the future universe state. For this reason, philosophers often avoid using the terms "predetermined" and "predestined", because these carry the connotation that somebody already knows the future U-state.

After the discovery of chaos in relatively simple nonlinear systems, it is generally agreed that humans will NEVER be able to predict the future U-state because our measurements only have finite precision, and we only have finite time to calculate. This does not rule out the idea that the universe is deterministic, as in Feynman's famous quote: "The universe integrates empirically", but it absolutely rules out our ability to make even short term weather predictions.
reilly
#36
Sep12-05, 03:47 PM
Sci Advisor
P: 1,082
Quote Quote by Crosson
Actually what you measure are positions, energies, momenta. People use wavefunctions to calculate energies, and then measure energies, and the next thing you know they are saying they have measured a wavefunction.
>>>>>>>>>>>>>>>>>>
RA

Well, how else do you measure probabilities? (I'm aware of the convergence difficulties and other matters of mathematical rigor) When you have a coin toss, you measure which face of the coin is up. Then you count them. And, generally, you'll find, a 50-50 or close thereto, split. Of course, you want to make as many measurements as you can. As I'm sure you must know, physicists do a lot more with wave functions than calculate energy levels.

My thesis concerned electron-proton scattering, and I certainly used wavefunctions. When you do a scattering experiment you measure the probability that, say, an electron scattered from a proton, goes to a particular angular position. Sometimes you measure both electron and proton positions. But, in any event, you measure the modulus of the appropriate wave function. I don't expect you to believe me, but how about Bohm? He devotes over 70 pages to scattering theory in his classic book, Quantum Theory, and clearly demonstrates what I've just stated -- as do countless books and papers.


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
C
All I am saying is that the complex-valued wavefunction is a hidden variable that is used to predict things that we actually measure, whereas Bohm's theory always speaks in terms of things we directly measure: positions, energies and statistical Hamilton-Jacobi functions. (How would a wavefunction be measured? With what sort of complex measuring device?)
>>>>>>>>>>>>>>>>>>>>>>>>>>.

RA
Generally speaking the wave function is exactly that, one of space and time and spin and...... If, in fact the wave function is a "hidden variable", in what space is this true? (Just to be precise, one normally does not consider a wave function as a variable.)

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
C
My point about orbits was obviously a miss. I am not claiming that copernican/ptolemaic (newtonian really) astronomy does not accurately predict the positions of celestial bodies. I was simply saying that the orbits we imagine the planets to move along cannot be directly observed.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
(RA) That's right for sure, certainly for complete orbits, or long sections thereof. It's not an issue of any consequence -- it well might be if our predictions of planetary motions were incorrect.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
C
Personally I don't give a crap about observation, but if someone attacks the causal (Bohmian) interpretation of QM on the grounds that quantum trajectories are inobservable (the "in principle" part comes from that unfounded assumption of QM that I brought up earlier), then I expect that person to think about which things we discuss in physics are truly observable: the truth is that many are not.

>>>>>>>>>>>>>>>>>>>>>.
RA
The fact that you speak so disparagingly of observations says, with all due respect, you don't know nuthin' about physics. Physics has been based on observation for many centuries. Without observations physics would be the nothing more than pure speculation, with no way to discern truth, just a time-killer for restless minds. -- barring a return to the divine right of kings.

I was interested in Bohm's ideas when I was a student, albeit many years ago. My professors kindly suggested to me that. if I wanted to be a professional -- which I did -- it would be wise to learn "mainstream" physics first, and then, if I felt the urge, to return to Bohm's work. Further, I sensed that many of my Profs had great respect for Bohm, as a very bright, able and accomplished physicist. I gave my students similar advice with respect to Bohm and the whole area of alternative interpretations of QM. In short, the standard track in any profession is: pay your dues, get your union card, start you career with some strength. (Bohm certainly did) --true for docs, lawyers, jazz musicians and blues singers, academics, .. Don't fall on your sword until there's a medic around.

And, my criticism of Bohm's hidden variables is that it has not produced any new physics, unique to its precepts. I know that many physicist have a similar position. Further, as I remember, computations are more difficult with Bohm's approach. Here's a challenge: compute the Lamb Shift for hydrogen a la Bohm's approach.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
C
Occam says that one should not increase, beyond what is necessary, the number of entities required to explain anything. Bohm's theory does not "increase the number of entities", it simply talks about a particle and a wave associated with the particle (the wave is a generalized Hamilton's statistical function).
>>>>>>>>>>>>>>>.
(RA)Strictly a matter of opinion.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
C
QM talks about both these things, but it speaks of the particle in a totally inconsistent nonsensical way (as if it teleports around through places it has "no probability of being". (RA-- How so?)

If the particle and its properties do not exist other then when they are measured, what sort of particle is that? Didn't someone accuse me of claiming the empire state building does not exist when we are not looking at it? How ironic that this is the world view of standard QM which I am against.
>>>>>>>>>>>>>>>>>>>>>>>>>>>

The QM you discuss, and the QM I've known and worked with for many years appear to be rather different. Particles exist only when observed? (David Hume could make a case for that position.) Nope. Most of us do not believe that, as amatter of pragmatism. You totally misstate the "world view of standard QM", and vastly overstate the importance of the arguments about interpretation. Day-to-day physics works with a pragmatic Born-Bohr interpretation, and most physicists are involved in day-to-day. It's pretty basic to assume the real objective world exists. And day-to-day physics makes the same assumption.

I never got back to Bohm because I found high energy theory much more interesting and challenging. (But, of course, I will admit a bias toward observation, which might disqualify my intellectual seriousness.) What in the world do you mean by teleportation?

Why does QM upset you so much? The fact that we can participate in this forum is totally based on QM -- as in semiconductors,. Have you actually taken a graduate level QM course?
Are you aware that with the use of wave packets, trajectories can be defined loosely? -- a staple of formal scattering theory.

If you wish to cling to your ideas about QM, then if you want to be taken seriously, you will have to cite chapter and verse, rather than handwaving and indignation, about what you consider to be the inadequacies of QM, and give strong support based on observations and or mathematics. But if you really don't give a crap about observations, then as I said above, you are not doing nor talking about physics.

Regards,
Reilly Atkinson

PS By the way, Locrian, your definition of determinism is exactly the one used in physics. Philosophy might well talk a different talk.


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