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Okay, I agree it's incomplete. I also agree that the standard interpretation (and quite a few of the non-standard ones) disagrees with the axioms. This does not make the physical theory itself meaningless, however--when it does make predictions, they've been borne out spectacularly by experiment. Calling it "meaningless" is an exaggeration; incomplete and philosophically unfounded, yes, but meaningless, no.

Well, it hasn't been stated in a meaningful way. A meaningful statement would be one that identifies the concretes observed--without confusing them with the observations--defines concepts based on their common characteristics, and states what we know about the nature of the units of those concepts and their relationships. None of the interpretations I am aware of even manages to identify the concretes without confusing them with the observations.

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Quantum physics is not a meaningful theory....I'll give your quantum physicist a hydrogen atom and if he predicts where exactly he'll find the electron, I'll give him ten thousand dollars.

Quantum theory does not even pretend to be complete. And to be meaningful, a theory needs to make statements that are consistent with the axioms of existence, identity, and consciousness.

Without intending to enter into a debate about Quantum Mechanics, please consider:

- the possibility that your request about predicting the exact location of the electron is meaningless

- the possibility that the notion itself of the exact location of the atomic electron is an anticoncept

- the possibility that it is not QM itself that is meaningless, but some (or most) of its philosophical interpretations

- that the axioms of existence, identity, etc. would not be contradicted if the notion of the atomic electron having an exact position and momentum to an arbitrary precision and at the same time, proves to be meaningless.

Alex

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It does not have to be -complete-.

Have to, for what purpose? It would have to be complete for the purpose of your implied assertion that it is complete.

No physical theory is complete to this date.

If I dropped a ball from my balcony, physics would be able to predict quite exactly how much time it would take to reach the ground, what velocity it would have when reaching the ground, how high it would bounce back, and so on. This, to me, means that the theory of the motion of macroscoping objects with velocities << c is complete.

And so are the theories of heat transfer and phase changes among macroscopic objects; of the reflection, refraction, and diffraction of light on macroscopic objects; of electric currents in macroscopic electric circuits--even ones including transistors!--of capillarity and the surface tension of liquids; etc. etc. ... pretty much all the science down to the level of atoms and molecules. It is only when you look inside the atom that the trouble starts, or when you begin to travel at velocities that are not dwarfed by the speed of light. The rest of physics, fortunately, has been developed before the 20th century--before anti-Aristotelianism came to be seen as a sign of a profound theory.

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Without intending to enter into a debate about Quantum Mechanics, please consider:

- the possibility that your request about predicting the exact location of the electron is meaningless

- the possibility that the notion itself of the exact location of the atomic electron is an anticoncept

In other words, that electrons are not particles. I have considered that to be a possibility for quite some time, and I'm sure I have not been the first one to consider that possibility. Many physicists certainly didn't think of light as particles before the photoelectric effect was used to justify jumping to the conclusion that light "sometimes" consists of particles.

- the possibility that it is not QM itself that is meaningless, but some (or most) of its philosophical interpretations

You guys keep using the word "some" here. Can you name any interpretation that is based on the primacy of existence and does not contradict the Law of Identity?

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Have to, for what purpose? It would have to be complete for the purpose of your implied assertion that it is complete.

If I dropped a ball from my balcony, physics would be able to predict quite exactly how much time it would take to reach the ground, what velocity it would have when reaching the ground, how high it would bounce back, and so on. This, to me, means that the theory of the motion of macroscoping objects with velocities << c is complete.

And so are the theories of heat transfer and phase changes among macroscopic objects; of the reflection, refraction, and diffraction of light on macroscopic objects; of electric currents in macroscopic electric circuits--even ones including transistors!--of capillarity and the surface tension of liquids; etc. etc. ... pretty much all the science down to the level of atoms and molecules. It is only when you look inside the atom that the trouble starts, or when you begin to travel at velocities that are not dwarfed by the speed of light. The rest of physics, fortunately, has been developed before the 20th century--before anti-Aristotelianism came to be seen as a sign of a profound theory.

Specific heats are not predicted correctly by classical thermodynamics. Classical physics has failed in both the small and the large. It does not account for atoms well and the Newtonian Gravitation Laws are wrong. Newtonian Gravitation does not account for the motion of planets in a strong gravitational field the precession of the perihelion of Mercury is not correctly predicted by Newton's law. Furthermore the bending of light around a massive body is incorrectly predicted by a factor of two. And the gravitational red shift is not predicted at all.

Classical electrodynamics cannot account for the stability of atoms whereas quantum electrodynamics does.

When a theory works, it works. And when it fails it fails. Classical physics fails in several significant ways.

Bob Kolker

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Roland, I think what AlexL means about knowing the specific location of an atom being meaningless, is that there is no such thing as absolute space (or for that matter, absolute time). This is not a problem, from an objective viewpoint, because all it does is confirm the very fact of being objective: that we choose something relative to us, and form principles about it (this is, in short, what relativity is about).

What quantum physics means, from what I understand it, is not that the universe is inherently unknowable - it just means we have to recheck our premises about what we mean about knowing the properties of something.

I'm thinking that you guys are talking past each other here, and in that other thread - I think you two should state your positions clearly, for all our sakes.

Bob, I disagree with you that Newton's Laws are wrong. They are not 'wrong'. They are inaccurate when taking into account larger bodies in space, due to the distortion in space-time caused by those large bodies, but they do prove what they set out to prove, and they are still used in Astrophysics for a number of things. What is, or was wrong, was the refusal to follow the results of them to a logical end, and to dismiss the old notions of a static universe or of space and time as being completely separate.

Edited by Tenure
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In other words, that electrons are not particles. I have considered that to be a possibility for quite some time, and I'm sure I have not been the first one to consider that possibility. Many physicists certainly didn't think of light as particles before the photoelectric effect was used to justify jumping to the conclusion that light "sometimes" consists of particles.

I do not understand your "in other words". You seem to assume that atomic and subatomic particles should have essentially the same properties we quite successfully use in describing balls falling from balconies; but: (1) there is no logical necessity for this to be the case, and (2) it is not the case.

You guys keep using the word "some" here. Can you name any interpretation that is based on the primacy of existence and does not contradict the Law of Identity? [and, from a previous post:] None of the interpretations I am aware of even manages to identify the concretes without confusing them with the observations.

First, I am speaking for myself: I do not necessarily endorse the views of Bob or others on the subject.

Second: for an attempt of an interpretation which dispenses with the observer and observation as the starting point of the quantum theory, try Mario Bunge, Philosophy of Physics, 1973, available in good science libraries. Read a few pages from the first chapter and see if the general approach makes sense to you; I bet you will be surprised...

Of course, as always, a critical reading is in order. And having studied some QM helps very much at a better understanding of the arguments, but for the purpose of judging the general philosophical approach, is nor absolutely necessary.

Alex

Edited by AlexL
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Specific heats are not predicted correctly by classical thermodynamics.

Because specific heat depends on atomic structure. That is not a macroscopic property. But once you have measured the specific heat of a substance, you can predict how hot it will get when you heat it--and that part of the science is complete and sound.

Classical physics has failed in both the small and the large. It does not account for atoms well and the Newtonian Gravitation Laws are wrong. Newtonian Gravitation does not account for the motion of planets in a strong gravitational field the precession of the perihelion of Mercury is not correctly predicted by Newton's law. Furthermore the bending of light around a massive body is incorrectly predicted by a factor of two. And the gravitational red shift is not predicted at all.

Classical electrodynamics cannot account for the stability of atoms

Which are precisely the kinds of things I excluded from my delineation of sound science.

When a theory works, it works. And when it fails it fails.

Exactly. My theory tells me how fast the ball will fall. Your theory does not tell you where the electron is.

Classical physics fails in several significant ways.

Please read OPAR.

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Roland, I think what AlexL means about knowing the specific location of an atom being meaningless, is that there is no such thing as absolute space (or for that matter, absolute time).

No, sorry, this is not what I mean. First, I am not talking about knowing, but rather about having (i.e. metaphysics). And second, the fact that the position is relative is also not what I was talking about.

I was pointing to the possibility that the simultaneously exact position and momentum of a body, which corresponds to our ordinary observation and intuition, is, for a macroscopic body (ball, etc.), an emergent property, which is not necessarily present under all circumstances at the microscopic level.

Alex

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I do not understand your "in other words". You seem to assume that atomic and subatomic particles should have essentially the same properties we quite successfully use in describing balls falling from balconies

Yes, I think the word "particle" has been quite inextricably associated with "ball-like." If we are identifying entities that are not ball-like, I would prefer that we find a different word for them--since they would really be a new concept.

First, I am speaking for myself: I do not necessarily endorse the views of Bob or others on the subject.

I knew that. In fact, I even knew it with the word "necessarily" excluded. :confused:

Second: for an attempt of an interpretation which dispenses with the observer and observation as the starting point of the quantum theory, try Mario Bunge, Philosophy of Physics, 1973, available in good science libraries. Read a few pages from the first chapter and see if the general approach makes sense to you; I bet you will be surprised...

Thanks for the lead; I'll try to get the book.

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Can you name any interpretation that is based on the primacy of existence and does not contradict the Law of Identity?

From what I know of it, Bohmian mechanics, for one.

After reading up on it a little, I am inclined to think you're right. The fact that it is the least frequently mentioned interpretation definitely seems to confirm it!

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Yes, I think the word "particle" has been quite inextricably associated with "ball-like." If we are identifying entities that are not ball-like, I would prefer that we find a different word for them--since they would really be a new concept.

It was quite a shock for the physicist to discover that the atom is not like a solar system in miniature. Concerning the necessity of introducing a new concept to denote specifically a microparticle -- Bunge came to the same conclusion ! (Chapter 5, section 2).

[about endorsing Bob's and others' views:] I knew that. In fact, I even knew it with the word "necessarily" excluded. :confused:

I do fully agree with Bob's enumeration of the failures of the classical physics; those are technical, not philosophic, failures. Most, but not all, of them touch domains which are outside the everyday experience (fast speeds, atomic world). Man has no direct perception of the atomic world and, without a strict discipline of a realist epistemology, may begin seeing ghosts...

Thanks for the lead; I'll try to get the book.

OK. I would be interested to know your opinion.

[from another post]specific heat depends on atomic structure. That is not a macroscopic property. But once you have measured the specific heat of a substance, you can predict how hot it will get when you heat it--and that part of the science is complete and sound.

Specific heat is a macroscopic property in the sense that an individual atom or a small group of atoms do not have such a property. This is related to the fact that the temperature, a property which gives sense to the specific heat, a a purely macroscopic emergent property.

Alex

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Concerning the necessity of introducing a new concept to denote specifically a microparticle -- Bunge came to the same conclusion ! (Chapter 5, section 2).

That's a good sign. :)

I would be interested to know your opinion.

I'll let you know when I get to read it. (I don't promise it will be soon, though; reading books is a very long-term proposition with me. I usually take several months to read any single book...)

I do fully agree with Bob's enumeration of the failures of the classical physics; those are technical, not philosophic, failures. Most, but not all, of them touch domains which are outside the everyday experience (fast speeds, atomic world).

Which means that they are outside of the domain of classical physics. When you know the bounds of the context within which you can apply classical physics, and do not try to apply it outside those bounds, you will find a theory that fully integrates all concrete facts of reality that we can observe within those bounds, and also fully integrates all the integrations among themselves--and states them all in the form of objective concepts and principles. You will find a theory that is not just a theory but actually deserves the name of knowledge.

Specific heat is a macroscopic property in the sense that an individual atom or a small group of atoms do not have such a property.

Oh, absolutely. When I said "That is not a macroscopic property," I was referring to atomic structure, not to specific heat.

And my point was that classical physics never ought to be used to try and predict macroscopic properties from atomic-level ones, because classical physics, limited to its proper domain, simply does not include such things as subatomic entities. Just like a handheld calculator with a precision of 10 decimal places does not include the square root of 1.000000001. If you typed that number into it and pressed the square root button, it would say "1." This does not mean that the calculator is broken or useless or "a failure" ; it simply means that 1.000000001 is on the very boundary of what it can deal with, just like atoms are on the very boundary of what classical physics properly deals with.

If you wanted to, say, multiply that number by 2, the calculator would give you the proper result. If you took its square root and squared it back, it would give you the wrong result. When you are on the edge of the domain of applicability, some of the operations will work and others won't; the same is the case with classical physics and atoms. But when you are safely inside the domain of applicability--say, you are interested in the square roots of three-digit integers to a precision of 4 decimal places--the calculator, just like classical physics, will produce the right results with absolute certainty.

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To be more precise: ... which has not been given to this day. Quantum physics is not a meaningful theory.

It is so meaningless that it has been indispensable to produce the computer on which you have typed "it is not a meaningful theory" The measure of merit in a scientific theory is correct predictions made and technology based on the theory. Quantum physics is the champion on both measures. Classical physics has failed on that score. Newton's mechanics and gravitation are -wrong-. Not very wrong, but wrong never the less. GPS calculations based on Newton's laws of gravitation produce significant errors. The relativistic corrections are necessary. Classical electrodynamics is -wrong-. It cannot explain the photoelectric effect. It cannot explain coherent light. It does not predict the Compton Effect, it cannot explain electron orbitals. It does not explain or predict atomic spectra and it does not even explain how stable atoms can exist at all. But it is correct enough to make non-transistor radios, incandescent lamps and the starter systems for automobiles.

I grew up with all these technologies based on classical electrodynamics. The first computers I ever worked on had vacuum tube circuits and memories consisting of iron rings. They worked, but they could never be made very small and very fast. They produced so much heat that very heavy air conditioners were necessary to keep them from burning up. Quantum theory is why your desk top computer is 10,000 times faster and smaller than the best computer available in 1959.

Newton's theories are categorically flawed. How so? Because they are based on an incorrect notion of space and time. Newton postulated time and space are absolute. Neither is absolute. Newton, at the time he worked, had no reason to suppose other than he did, so he has not done bad science. His thinking was in line with the evidence he had in hand. In fact, Newton invented mathematically based theoretical physics, and the character of the science he crafted is with us even today, although his theories have been replaced. Newton -invented- the business.

Bob Kolker

Edited by Robert J. Kolker
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You keep saying the same thing over and over again. I don't think it's necessary for me to keep addressing it over and over again.

That I do. You keep making the same mistake and I keep correcting you.

Meaningless theories do not lead to superlative technologies.

Bob Kolker

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I'll let you know when I get to read it. (I don't promise it will be soon, though; reading books is a very long-term proposition with me. I usually take several months to read any single book...)

Oh, no, I meant a feedback after reading only a few pages from the first chapter :-)

Which means that they are outside of the domain of classical physics. When you know the bounds of the context within which you can apply classical physics, and do not try to apply it outside those bounds, you will find a theory that fully integrates all concrete facts of reality that we can observe within those bounds, and also fully integrates all the integrations among themselves--and states them all in the form of objective concepts and principles. You will find a theory that is not just a theory but actually deserves the name of knowledge.

The physics at the end of the 19th century, known as classical physics, had two problems:

- it was incomplete in the sense that the yet unknown phenomena at molecular level were hidden within empirical parameters (specific heat is one example)

- it was internally contradictory; for example, as Bob noted, classical mechanics combined with classical electricity predicted that neither we, nor any normal objects could exist, and everything should collapse.

The notion that the classical physics is/was a fully integrated and satisfactory theory for explaining all we need to know about reality at the level accessible to our direct perception ("it's proper domain of applicability", as you say), is wrong. It is also wrong to claim, as some do, that the classical physics is the product of reason, but the new physics - of the unreason. Both are products of the scientific method, of a common sense, rational epistemology, where reality is the supreme judge. We should not confuse what scientist are doing with what they are saying they are doing; this is valid for our time, but - make no misstake - also for the 19th century.

The new physics is not dispensable: as knowledge, it enormously expands in various directions our understanding of the nature, and in particular establishes why and where is the classical physics correct, and where it isn't. It also explains, and also predicts, many essential macroscopic phenomena. On the practical level, it is responsible, as Bob mentioned, for most of the terrific technological advances of the last 50 years (including in medicine and biology).

Alex

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Meaningless theories do not lead to superlative technologies.

Ah, now you got my attention! This is a very interesting premise; it can be used to prove something that I have always suspected but had no way of demonstrating.

I have a theory that is based on a mathematical formalism, which describes some empirical observations. The formalism states:

2 ^ 8 = 256

Now, this can be used to predict quite a number of things, and of course has played a crucial role in the development of the very computer and Internet I am using to convey this message to you, as well as GPSes, and countless other superlative technologies. But people keep asking: Why is it exactly 256? Why is it not another number?

There are several possible interpretations of the formalism. My personal favorite is the Crackhead Kantian Interpretation, which holds that 2 ^ 8 can have a broad range of values, but the value we actually observe is always the result of a so-called "collapse" of that range into a single value. The specific formula for finding the collapse is:

2 ^ 8 = 621 - K + L

where L is a time-dependent parameter which has the value of 0 in certain years and 1 in others, with an approximate probability distribution of 3:1, and K is the number of days that the adressee of this message has ingested cocaine in the previous calendar year. This year, L = 0, so substituting K = 365, we see that 2 ^ 8 = 256, which perfectly predicts the empirical results.

The Crackhead Kantian implementation has sometimes been criticized for not observing Occam's Razor, and some other pesky philosophical stuff like the primacy of existence and the Law of Identity. But, as you have eloquently stated, when a theory works, it works. It can't be wrong if my computer relies on some of its mathematical formalism, can it now! And as an added bonus, it also demonstrates that K = 365.

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  • 8 months later...

As you can see, you last post left me speechles for over eight months :) , during which I tried to guess what was your point, given that the subject was quite interesting.

I had a hypothesis or two, but I think I'd better ask.

So: what idea are you trying to illustrate with your so called formalism and, generally, with this post?

Alex

Edited by AlexL
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Okay, I'll give your quantum physicist a hydrogen atom and if he predicts where exactly he'll find the electron, I'll give him ten thousand dollars.

Quantum theory does not even pretend to be complete. And to be meaningful, a theory needs to make statements that are consistent with the axioms of existence, identity, and consciousness.

Exactly why does a theory that is in line with the axioms of existence, identity, and consciousness have to be micro-deterministic? As far as I know, the idea(s) of existence/identity is (are) not contradicted, nor are its corollaries of entities and causality. An entity that follows the law of causality need not have a precise position or momentum to be and do so. The facts that we can form a concept of an electron and put bounds on it are perfectly compatible with some level of stochastic behavior. Stochastic does not mean utterly chaotic. It simply means that its course of action is not fixed beforehand.

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The very idea of a particle of matter having a pinpoint location is wrong. An electron has size, an extent in space. This is a logical necessity because if the electron mass and charge were concentrated into a space of zero extent that would create an infinity of density of mass and charge, but infinities do not exist. It makes no sense to demand an electron be located to a spot smaller than or within itself.

Edited by Grames
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Exactly why does a theory that is in line with the axioms of existence, identity, and consciousness have to be micro-deterministic?

Exaclty where did I claim that it had to be "micro-deterministic" ? (Hint: this is the first time I've seen that phrase...)

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The very idea of a particle of matter having a pinpoint location is wrong. An electron has size, an extent in space. ... It makes no sense to demand an electron be located to a spot smaller than or within itself.

The electron size ("classical electron radius") is of the order of 10^(-15) meters, the characteristic size of an electron "cloud" (Bohr radius) is 10^(-11). The electron is 10'000 times smaller than it's "delocalization". Thus, the electron's size (or, better, "size") is out of the picture in our context.

Alex

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