Philosophy and Physics

[stephen_speicher]

Stephen Spencer, you've provided attributes of some entities which scientists are now trying to positively identify.  Please cite one [predicted] attribute of that entity which is under discussion (TEWIUD).

Polarization, momentum, energy, coherence, etc...

(What is a "TEWIUD"?)

I did not complain that we cannot directly observe TEWIUD, but that we have never observed it, directly or indirectly, by any means whatsoever, nor do we have any reason to expect to aside from what I consider to be an arbitrary a priori hypothesis.

Who is this "we" that you refer to? The indirect effects of which I speak have been observed in countless thousands of quantum experiments by real physicists. To understand the details of this requires a thorough knowledge of experimental physics and a detailed understanding of the theory. I have both.

As to an "arbitrary a priori hypothesis": Such an assertion is itself arbitrary, if not backed up by a technical grasp of the physics involved. If you are prepared to do just that, feel free to make your technical case on the forum devoted to this. We welcome people with a good grasp of the technicalities of quantum field theory and relativity. But, to get an audience there, you must make a case, not present arbitrary assertions.

[stephen_speicher]

Stephen

y needs more of a philosophic discussion about Parmenides and his reasons for believing the universe must be a plenum, than he needs a physics discussion pertaining to what that plenum might or might not actually be.

Well, Parmenides only work ("Peri Physeos") is a bit obscure, and written in a sort of verse. But, here is one famous sentence from a translation of that work.

"Nor is there any more of it here than there, to hinder it from holding together, nor any less of it, but it is all a plenum, full of what-is. Therefore, it is all continuous, for what-is touches what-is."

But, this is not a very complex philosophic issue, and there is not too much to be said about it. Some philosophers have found a multitude of ways of saying the same thing, sometimes over and over. It all boils down to a simple grasp of "What is, is. What is not, is not."

[MinorityOfOne]

Stephen (or others),

I recently came across a brief mention of Dirac's ether theory. From what I read, certain of his equations predicted the existence of "negative protons." He concluded that space could be literally full of negative protons, which would themselves be unobservable but would (according to his calculations) have effects consistent with established observations.

I was a little reluctant to even bring this up, since for all I know this is an utterly dumb question. But could this be a sort of ether? Unless I'm misunderstanding it (which I very well could be), it would satisfy the requirement that something exist everywhere, and it wouldn't violate the Michelson-Morley experiment.

So I'm wondering: was the text I read correct in saying that Dirac's theory of negative protons is consistent with observations? Would it, in fact, satisfy the requirements of the law of identity? And finally, for people who know more about it: if the answer to those questions is "yes", is there any way in principle to test whether Dirac's theory is correct?

[AwakeAndFree]

satanist wrote:

Using the word 'through' is merely a convention, an obvious holdover from our ongoing human context of living in ( and moving through ) an atmosphere, where we do move through air ( or various liquids ) in our normal existence.

Is being IN someplace also a mere human convention?

Because you can't be IN a place, or SOMEwhere, or go TO, or come FROM - if there isn't anything to be in, go to, or come from.

Also - suppose that movement was seen simply in relation to other objects. Relation - by what standard? This object is in HERE, and that object is in THERE.

If this was just an attribute of objects - it wouldn't be transferable. Can't you say that I am NOW in the same place something else WAS?

In all these senses there must BE something that exists independent of objects. A place for object to be in, pass through, go to, come from.

Therefore, RadCap is right - and there can be no action from afar.

[stephen_speicher]

Regarding Matt's questions about Dirac and the ether:

I do not know whether the confusion is in the text which Matt used as a source (do not be surprised that such confusion abounds) or whether Matt is misremembering what was said. In either case, the brief description is not at all correct. The reference is to what is known in the literature as the Dirac Sea, which had some value as a transitional theory in the development of quantum mechanics and has since been superseded by much more generalized approaches.

Briefly, in the late 1920s Dirac was disturbed that a number of physicists, including Heisenberg, sort of accepted a relativistic quantum theory of the electron which Dirac knew not to be consistent with his own approach (transformation theory). Dirac recognized (correctly) that the negative-energy solutions in that approach conflicted with what was then known about atoms. In a rather brilliant and daring move, Dirac postulated that these negative-energy levels were already filled and therefore could not accept any further electrons, and he hypothesized a sea of infinite charge density along with a sea of infinite negative-charge density. In a 1930 paper Dirac suggested:

"Let us assume that there are so many electrons in the world, that all the most stable states of negative energy are occupied, or, more accurately, that all the states of negative energy are occupied except perhaps a few of small velocity .... We shall have an infinite number of electrons in negative-energy states, and indeed an infinite number per unit volume all over the world ... We are therefore led to the assumption that the holes in the distribution of negative electrons are the protons."[1]

This is Dirac's hole theory with protons as holes in an infinite sea of negative-energy electrons. What Dirac failed to recognize was that, rather than protons, he had described anti-electrons -- the positron! Just two years later, in 1932, physicist Carl Anderson of Caltech discovered the positron, for which he was awarded the Nobel Prize in 1936. Dirac's mathematics led to anti-matter, but Dirac did not realize it at the time.

This hole theory of Dirac's never provided exact solutions, and going beyond first approximations, solutions were either infinite or meaningless. Because of Dirac's stature the mathematics of these holes in a sea of negative-energy electrons was utilized for several years, but then gave way to a theory of Pauli and Weisskopf, which Yukawa used in 1937 to formulate the advance of the relativistic meson theory. It is hardly necessary to point out the gaping philosophical flaws in the theory, but regardless it could not even lead to further advancement as physics itself progressed.

As an aside, in my view Dirac is an overrated genius in regard to physics. There is a group of ether supporters -- typically also supporters of Bohm -- who have a somewhat displaced connection to Dirac. While Dirac certainly deserves a great deal of credit for his work in quantum theory, his basic approach and philosophic bent is a bit strange. Dirac was passionate about beauty in mathematics, to the point where the mathematics had a life of its own, independent of any physical theory. Dirac noted:

"a good deal of my research work in physics has consisted in not setting out to solve some particular problem, but simply examining mathematical quantities of a kind that physicists use and trying to fit them together in an interesting way regardless of any application that the work may have."[2]

And,

"... physicists generally have come to believe in the need for physical theory to be beautiful, as an overriding law of nature. It is a matter of faith rather than of logic.... The moral of the story is that one should have faith in a theory that is beautiful. If the theory fails to agree with experiment, its basic principles may still be correct and the discrepancy may be due merely to some detail that will get cleared up in the future."[4]

There is no question that Dirac was brilliant and that he contributed to quantum mechanics, but, nevertheless, he was a bit of a strange-thinking man.

[1] P.A.M. Dirac, "A Theory of Electrons and Protons," Proceedings of the Royal Society of London, Series A, Vol. 126, No. 801, pp. 360-365, January 1, 1930.

[2] P.A.M. Dirac, International Journal of Theoretical Physics, 21, pp. 603-605, 1982.

[3] P.A.M. Dirac, Letter, The Scientific Monthly, Vol. 79, No. 4, pp. 268-269, 1954.

[MinorityOfOne]

Thanks for the info, Stephen. I was probably reading too much into what I read -- Dirac was only given about a paragraph in the text. (And I was speaking from memory.)

[stephen_speicher]

Thanks for the info, Stephen.  I was probably reading too much into what I read -- Dirac was only given about a paragraph in the text.  (And I was speaking from memory.)

You're welcome, Matt. Dirac was an interesting guy and he deserves to be focused on more when relating historical accounts as well as discussing technical contributions to quantum mechanics. In a real sense Dirac was the father of quantum electrodynamics, in that it was some of his ideas which Feynman et al picked up on in the development of that field. I think Dirac is often given too much credit in some areas, and not enough in others.

[Marc K.]

At this late date it seems as though y_feldblum has already been convinced (perhaps not).

I’ve been intrigued, though at times confused, by this thread. I’ve been trying to work it out in my head using concrete examples in place of jargon. Would Stephen Speicher and RadCap (with whom I am in agreement) be so kind as to analyze my thought process and let me know if I’m in the ballpark?:

Everything that is part of the Universe exists.

There is space between atoms. Even solids consist of mostly space. In air the space between atoms is greater. In the “vacuum” of interstellar space the space between atoms is even greater. I say “vacuum” in quotes because there are still atoms in interstellar space, they are just extremely rare. The space between the atoms in interstellar space and the space between atoms in a solid is metaphysically the same. This space is part of the Universe (all that exists) and thus it exists.

This is my hypothesis. To prove it I tried to come up with a common sense, readily apparent example:

I am standing in a room surrounded by air molecules and the space between the molecules. I take one step forward and displace some of those molecules. If the space between those molecules didn’t exist, then some of the molecules in my body would now exist in non-existent space.

It seems obvious that this could not happen. Is this thought experiment valid and logical or have I somehow used circular logic?

I have no idea of what this space is composed and I don’t know if by “ether” you mean “composed of particles”.

But I think what we are speaking of is “the fabric of space-time” which I think (depending on the user) is equivalent to: ether, plenum, space, fabric of the Universe, space-time continuum, empty space, etc...

What do you think?

[stephen_speicher]

Is this thought experiment valid and logical or have I somehow used circular logic?

The problem with thought experiments which attempt to make nonsensical things real -- things which contradict fundamental axioms like identity -- is that nonsensical things cannot be made real, so often the thought experiment leads to confusion. In my opinion, I think it better to focus on making the positive things real. In the appendix of ITOE, page 149, Ayn Rand was asked about the concept "nothing," to which she, in part, responded:

"That is strictly a relative concept. It pertains to the absence of some kind of concrete. The concept 'nothing' is not possible except in relation to 'something.' Therefore, to have the concept 'nothing,' you mentally specify—in parenthesis, in effect—the absence of a something, and you conceive of 'nothing' only in relation to concretes which no longer exist or which do not exist at present.... It is very important to grasp that 'nothing' cannot be a primary concept. You cannot start with it in the absence of, or prior to, the existence of some object. That is the great trouble with Existentialism, as I discuss in the book [page 60]. There is no such concept as 'nothing,' except as a relational concept denoting the absence of some things."

I have no idea of what this space is composed and I don’t know if by “ether” you mean “composed of particles”.

The history of the ether is a facinating subject, and historically the ether has taken on many different forms. Unless you are interested in the details of various scientific theories which have attempted to give reality to "empty space," regardless of whether the ether consists of particles or, say, schmooballs, there must be something everywhere in the universe. The universe is a plenum; it is full, no gaps, no truly empty spaces.

But I think what we are speaking of is “the fabric of space-time” which I think (depending on the user) is equivalent to: ether, plenum, space, fabric of the Universe, space-time continuum, empty space, etc...

You have the right idea, although the technical meaning of some of these words is not the same as others. The point to stress, again, is that all of existence is something, whatever the nature of that something is.

[War]

That's why we have religion, lol