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Tuesday, December 31, 2013

Site compares Poincare to Einstein

Craig Feinstein sends this 2010 site:
The father of relativity theory : Einstein vs Poincaré

We saw that it is Poincaré who names and formulates the principle of relativity, names and corrects Lorentz transformations, reports and exploits its group structure. To these examples, we could add that he establishes the method for synchronizing clocks by light signals (La mesure du temps, Revue de métaphysique et de morale, T.6, janv 1898), the formula of additivity of velocities, the invariance of Maxwell's equations in vacuum, and the hypothesis of the speed of light limit (Poincaré, 1905). Let's not forget that he also already uses a quadridmensional formalism that will inspire the future works of Minkowski, and then some. What is left?

He clearly masters most of the concepts and technical tools of what we call now the special relativity theory, except (and it is fundamental!) that it is to him just corrections brought to Lorentz works, part of a dynamics, and what's more, depending upon Maxwell's electromagnetic theory.
That is correct. Lorentz created special relativity theory as a way of reconciling Maxwell's electromagnetic theory with the Michelson-Morley experiment, and Poincare perfected Lorentz's theory.
Moreover, the principle of relativity concerns space-time and gives to it a physical meaning even if this space is empty, baring no body (it is a kinematics, that is to say a condition for the expression of dynamics), which Poincaré thinking about dynamics only could neither conceive, nor accept (Paty, 1987, p15).
This is crazy. Einstein does not have a spacetime theory. Poincare certainly did conceive and accept a spacetime theory where the Lorentz transformations are realized as the isometries of a 4-dimensional non-Euclidean geometry.

Like most everyone else, Johann reviews the facts and somehow credits Einstein anyway:
That's what makes Einstein the real father of the theory, because he presents in his 1905 paper all of these points (except the importance of the group structure of Lorentz transformations) in a coherent theory, building a kinematics on which the laws of physics will depend (and not the other way around), including those of electromagnetism.

Still, Poincaré surely stays a great and major precursor amongst all physicists and mathematicians who played a role in the history of the theory of special relativity.
No, Einstein did not present all of those points. He did not have the Lorentz group, the covariance of Maxwell's equations, or the 4-dimensional structure of spacetime. And where Einstein is getting relativity points correct, he is mostly recapitulating what was done years earlier by Lorentz and Poincare.

The main credit for Einstein is for claiming a theory broad enough for all the laws of physics. But it was Poincare who did that, not Einstein. Poincare had a spacetime theory that he applied to gravity. Einstein only had a way of understanding electromagnetism.

Johann admits that Einstein did not have the 4-dimensional spacetime, and only got it from Poincare and Minkowski years later:
To respond ..., first you're right saying that Minkowski popularized Poincaré's work and influenced Einstein, but it was AFTER its Cologne lecture of 1908. ... You could say that Einstein didn't grasp the 4 dimensionality of the theory before Minkowski and you would be right! He even said to Minkowski that it was an unnecessary complication, and recognized only later when working on the generalized theory that he was wrong.
That's right, and if you view the 4-dimensional spacetime as the crucial idea, that idea can be traced from Lorentz to Poincare to Minkowski to widespread acceptance, without Einstein having anything to do with it.
To conclude, I'd like to add that even if Einstein had read "La dynamique des électrons" (which I firmly believe he didn't, even if I can't prove it any more than you can prove he did), contrary to what you say his article did bring something fundamentally new and different than any previous work, including Poincaré's, namely 1° the concept of condition for the laws of physics, 2° the correct interpretation of space and time measurements and 3° A STRUCTURED AND CLEAN THEORY.
A condition for the laws of physics? Only Poincare explicitly looked for laws of physics obeying Lorentz group invariance. Only Poincare said relativity was a theory about our methods of measurement. And the only way I know to describe relativity as a coherent structured clean theory is to express it a non-Euclidean geometry, and that was done by Poincare in 1905 and Minkowski in 1908.

A separate post says:
Note that Henri Poincaré was already looking for all the invariants of the Lorentz group, using infinitesimal generators (which relates to the Lie algebra approach of our days) ! and this in 1905 (see our second bibliographic reference), the same year Einstein published his article, which Poincaré had still no knowledge...

However, let's not make the mistake of attributing relativity theory to Poincaré, since he never built any complete theory (in physics anyway), and was merely correcting and improving other physicists' work (Maxwell, Lorentz, etc.).
Not a complete theory? Poincare has all of the relativity formulas that Einstein had in 1905 and more, and somehow it was not a complete theory? That is ridiculous.

Crediting Einstein has to be based on what was different about Einstein's 1905 work, and his main virtue here seems to be that he never credited his sources. Lorentz and Poincare showed how their work built on previous work, so I guess they "merely" improved it. All science is correcting and improving previous work.

Craig writes:
If this is true, I can't see how Einstein got credit. Poincare's theory predicts everything that Einstein's theory predicts. The only thing that Einstein did was clean it up, get rid of the aether, make it sound nicer. But that is not science.

I think in that period of time, the early 1900's, the idea that there are no absolute standards was becoming popular in intellectual circles. Einstein came along and showed that physics could be put into this relativistic framework. Because of this, the intellectuals of that time crowned Einstein a hero, since it justified their worldview.

Today, society accepts the idea that there are no absolute standards. And Einstein is still the king. He was even made Time's man of the century. Poincare was just a man who played along with equations that predicted the motion of bodies, while Einstein was a man who got rid of absolutism in nature. So what if Poincare was just as right as Einstein?
Poincare was the one who wrote a popular 1902 book saying that there is no absolute space or time, and no aether.

I have heard it claimed that relativity and Einstein were popular among intellectual non-scientists because of confusion with relativism.

Wednesday, December 25, 2013

Dilbert cat in a box

Today's Dilbert carton is on Schrödinger's cat:
207819.strip - Dilbert Copenhagen cat
Actually, this is a common misunderstanding. The Copenhagen interpretation never says that a cat "is neither dead nor alive". It says that the cat's wave function can be represented as a superposition of dead and alive states until a determination (ie, measurement) can be made. You can interpret the superposition as the observer's lack of knowledge. Some other interpretations require the cat to be dead and alive in parallel universes, or some such nonsense. Copenhagen says nothing of the kind, as it takes the more scientific approach of only addressing what is observable. There are 100s of published papers where physicists excitedly brag about putting an electron or something else into a "cat state". A recent example is Storing Quantum Information in Schrödinger's Cats. These superpositions are part of quantum theory, and always have been.

Plain English arguments for quantum computers

MIT professor Scott Aaronson is forever trying to explain the wonders of nonexistent quantum computers, and now he tries with only common words:
You might wonder, why is it so hard to build these new computers? Why don’t we have them already? This part is a little hard to explain using the words I’m allowed, but let me try. It turns out that the new computers would very easily break. In fact, if the bits in such a computer were to “get out” in any way — that is, to work themselves into the air in the surrounding room, or whatever — then you could quickly lose everything about the new computer that makes it faster than today’s computers. For this reason, if you’re building the new kind of computer, you have to keep it very, very carefully away from anything that could cause it to lose its state — but then at the same time, you do have to touch the computer, to make it do the steps that will eventually give you the right answer. And no one knows how to do all of this yet. So far, people have only been able to use the new computers for very small checks, like breaking 15 into 3 × 5. But people are working very hard today on figuring out how to do bigger things with the new kind of computer.

In fact, building the new kind of computer is so hard, that some people even believe it won’t be possible! But my answer to them is simple. If it’s not possible, then that’s even more interesting to me than if it is possible! And either way, the only way I know to find out the truth is to try it and see what happens.
Does that sound as it he is on track to prove something possible? Not to me. I am among those who believe it will be impossible, and I am very skeptical of the supposed progress.

He also argues that P != NP because verifying a proof ought to be much easier than finding an original proof. That is a reasonable argument. If it turns out that P = NP, then we would have to revise a lot of what we think about complexity, so we should be very skeptical of any such claim. Likewise we should be skeptical about quantum computing.

Monday, December 23, 2013

Silly use of uncertainty metaphor

People are often saying nonsense about the uncertainty principle, but it is annoying to see it in a reputable science magazine.

Walter G. Montgomery says he has a PhD and writes in Scientific American:
In quantum mechanics, Heisenberg’s Uncertainty Principle holds that it is impossible to determine both the position and momentum of a particle. Heisenberg’s breakthrough relates to a subject of vital importance to America: the need for better communications practices in the science and technology fields.

Communications is my profession, and I am concerned by what I see. ...

The third and most challenging way in which science and technology communications differ from communications practices in other fields brings us back to the Uncertainty Principle. In other realms, superior communications professionals work side-by-side with clients to craft consistent and compelling messages and documents that concern finite situations that occur in specific spaces and points in time. They may, for example, draft a press release to announce a company acquisition, a statement explaining a C-level executive succession or an internal communications piece that describes to company employees the importance of a new product or service launch. In each of those cases, our job is to explain what has happened in terms that are as concrete and definitive as possible.

Messaging around science and technology, however, is a different story, because science rarely involves certainty. Rather, science is a quest for objective truth that might never achieve a final, definitive outcome. Given that science is an ever-unfolding story in which the goal posts keep moving—and that today’s vouchsafed hypothesis might be modified six months from now—crafting solid messaging around uncertainty becomes a unique communications challenge.
No, the uncertainty principle is not about our lack of knowledge about some final objective truth that we can might never achieve. There is plenty of certainty in science. Science has more certainty than any other field, except mathematics. Reporting on scientific experiments and other progress is just as certain as reporting in the business world, if not much more so. Usually scientists are at least trying to tell the truth in their press releases, while business press releases nearly always tell some partial truth designed to promote the sale of a product.

Lumo rants:
The probabilities in quantum mechanics do have exactly the same physical interpretation as the probabilities resulting from ignorance in classical statistical physics – i.e. as the probabilities calculable from the distribution functions on the classical phase space. The actual difference between classical statistical physics and quantum mechanics is the uncertainty principle that governs the latter. The uncertainty principle says that some degree of the ignorance is fundamentally unavoidable, independently of the chosen observer, her measuring apparatus, or methodology. Mathematically speaking, the new feature of quantum mechanics is the nonzero commutator between generic enough observables. It is not just a specific technical feature of some particles; it is a key conceptual rule that holds everywhere in this quantum world: The truths themselves refuse to commute in this Universe.

It seems very obvious to me that Scott Aaronson doesn't understand these basic conceptual findings about the character of probabilities in statistical physics and quantum mechanics. He's not the only one; almost everyone else who loves to write "popular" texts about quantum mechanics these days is similarly deluded. These people maintain some insane anti-Bohr, anti-Heisenberg sentiments that prevent them from seeing that by these assaults against the deepest findings done by these two men (and their school), they are exactly as canonical crackpots as "biologists" who love to constantly assault Darwin's "mistakes".
He is a little hard on Aaronson, who obviously understands quantum mechanics very well, but is correct about the uncertainty principle. The fundamental new feature of quantum mechanics is that observables do not commute, thereby necessitating and uncertainty in their measurements. Bohr and Heisenberg had this part of the theory exactly correct, and Einstein had it wrong. Progress in the last 75 years has only affirmed what Bohr and Heisenberg said. I cannot explain why Aaronson seems to have a different view, and writes:
You might say that Bohr and Heisenberg got closer to what we now know to be the truth about QM (i.e., that local hidden-variable theories can’t work, and the probabilities in QM can’t have an ordinary ignorance interpretation like in QM). ...

Bohr and Heisenberg both had the properties of

(1) putting way more stress on “wave/particle complementarity” and the uncertainty principle than we’d put today,

(2) bizarrely, saying almost nothing about the aspects of QM we do see as central today, like entanglement, the enormous size of Hilbert space, or amplitudes being complex-valued analogues of probabilities, ...
The probabilities in QM certainly do have an ordinary ignorance interpretation, with that ignorance being the ignorance of measurement. They are not interpreted as probabilities of hidden variables, of course, as Bohr and Heisenberg rejected the sort of hidden variable theories that Einstein and others stubbornly and wrongly clung to.

Entanglement is overrated. The enormous size of Hilbert space is a trivial mathematical fact, and not that important unless you are arguing for some silly theory like the Many Worlds Interpretation. I also do not agree that the amplitudes are complex-valued analogues of probabilities. The amplitudes can be used to calculate probabilities, but that's all. Aaronson has his own popular book on quantum mechanics, but he has some distorted views.

Saturday, December 21, 2013

More evidence against SUSY

Here is the evidency against supersymmetry (SUSY):
New measurements of the electron have confirmed, to the smallest precision attainable, that it has a perfect roundness. This may sounds nice for the little electron, but to one of the big physics theories beyond the standard model, it's very bad news. 'We know the Standard Model does not encompass everything,' said physicist David DeMille, of Yale University and the ACME collaboration, in a press release. 'Like our LHC colleagues, we're trying to see something in the lab that's different from what the Standard Model predicts.' Should supersymmetrical particles exist, they should have a measurable effect on the electron's dipole moment. But as ACME's precise measurements show, the electron still has zero dipole moment (as predicted by the standard model) and is likely very close to being perfectly round. Unfortunately for the theory of supersymmetry, this is yet another blow.
The LHC has also failed to find evidence for SUSY, but the leading experts are unfazed:
The embarrassing fact of no SUSY at the LHC does get fleeting mention, but John Schwarz assures everyone that in his view, there is no question that superpartners exist, whether or not the LHC ever sees them. The multiverse is seen as the answer to all problems, ...
SUSY is mathematically interesting, and has some conceptual appeals, but it conflicts with the evidence. Are we scientists or not? It is time to accept reality.


Update: Here is a Slashdot comment:
But the proponents of SuSy claim that their theories are elegant!

Have you ever seen a Nima Arkani-Hamed talk? (there are some on youtube and elsewhere). Most annoying is that not only does he rant and rave about how wonderfully simple and elegant his supersymmetry is, but he decorates those claims with embellishments like "they must be true".

Even more annoying is when a big potentially-confirming experiment is concluding, he's proud to say what result he expect that will confirm this theories, add that if he doesn't get them he'll scrap his theories, and then when the results don't confirm his theories, he shuts the f*** up briefly, and then resumes pushing the same old theories.

If you want good science. Don't look in the direction of that branch of physics, you'll have more luck in psychotherapy, economics, or astrology.
Supersymmetry is not really simpler or more elegant. It requires twice as many particles and about five times as many free parameters. We would never have any hope of determining those parameters.

Thursday, December 19, 2013

Grossmann's contribution to relativity

Tilman Sauer just wrote a detailed paper on Marcel Grossmann and his contribution to the general theory of relativity.
Grossmann's contribution to the Entwurf theory consisted in the following.

* He clarified the mathematical foundation of the theory based on a general line element (8) and generalized the concept of a tensor to a structure of n th rank in m-dimensional space.

* He identified the absolute differential calculus by Ricci and Levi-Civita as the relevant mathematical toolbox for the problem of a relativistic theory of gravitation and transformed it into a tensor calculus both with respect to notation and by generalizing it to mixed tensor densities.

* He proved that the conservation law for matter (11) was a generally covariant equation by showing that it expresses the covariant divergence of Theta-mu-nu.

* He identified the Riemann tensor as a relevant and rich resource for the problem of constructing generally covariant gravitational field equations, and he showed Einstein several ways of extracting a second rank object from the Riemann tensor that would have the desired limiting form in the case of weak static fields.

* After the failure of the mathematical strategy of constructing a field equation from the Riemann tensor, he proved the central identity (39) from which the gravitational field equations of the Entwurf theory were read off.

* In joint work with Einstein, he showed how the Einstein-Grossmann theory can be formulated in terms of a variational principle and clarified its transformational properties in light of the hole argument
This is a substantial part of the theory, but Einstein wrote privately:
Grossmann will never lay claim to being co-discoverer. He only helped in guiding me through the mathematical literature but contributed nothing of substance to the results.
Grossmann ought to be considered a co-discoverer. After the collaboration, Einstein wrote nonsense papers for over a years, and did not get back on track until he collaborated with Hilbert in 1915.

It appears that Grossmann and Hilbert are not credited because of a prejudice against mathematicians. Their contributions are considered to be just math, not physics. But finding the equations of general relativity was largely a mathematical problem, given Newtonian gravity and special relativity.

Tuesday, December 17, 2013

Rovelli defends Aristotle

Physicist Carlo Rovelli has just written an excellent summary of Aristotle's physics
I show that Aristotelian physics is a correct approximation of Newtonian physics in its appropriate domain, in the same precise sense in which Newton theory is an approximation of Einstein's theory. Aristotelian physics lasted long not because it became dogma, but because it is a very good theory.
This is important because Aristotle is widely reviled for stunting physics with wrong ideas, and requiring a Kuhnian revolution to overturn them.
Aristotelian physics is often presented as the dogma that slowed the development of science. I think that this is very incorrect. The scientists after Aristotle had no hesitation in modifying, violating, or ignoring Aristotle's physics. ...

In my own field of research, theoretical physics, a "vulgata" of Kuhn's incommensurability thesis has strong hold. According to this vulgata, advance in science is marked by discontinuity, the greatest the discontinuity the strongest the advance, and not much more than the phenomena survives across the discontinuity. This has fostered a style of research based on the ideology of discarding past knowledge as irrelevant and working by "guessing" possible theories. In my opinion this ideology is one of the reasons for the current sterility of theoretical physics.

Science generates discontinuities and constantly critically reevaluates received ideas, but it builds on past knowledge and its cumulative aspects by very far outnumber its discontinuities.
Rovelli is exactly correct. This blog's motto, that nature makes no jumps, refers both to physical law and to the accumulation of scientific knowledge. The whole concept of scientific revolutions is mistaken because the supposed discontinuities do not exist.

(The term vulgata means early Latin and Greek translations of the Bible.)
From this perspective Aristotle's physics deserves a sharp reevaluation. With all its limitations, it is great theoretical physics. Its major limitation is that it is not mathematical. ...

Of course Galileo, master of propaganda and grand master in the use of words, did his best to ridicule Aristotle, in the effort to win a difficult battle against a giant. From this, much of the bad press suffered by Aristotle's physics followed. ...

Aristotle's physics bad reputation is undeserved, and leads to diffused ignorance:
Right again. Aristotle was a genius who greatly advanced science. Sure, his work seems primitive compared to today's quantitative physics, but he was on the right track and he inspired progress.

It was not just just Galileo and Kuhn who unfairly trashed Aristotle, Bertrand Russell also did:
Then we get a hint of Russell's frustration: "almost every serious intellectual advance has had to begin with an attack on some Aristotelian doctrine; in logic, this is still true at the present day" (160).
and this:
“Aristotle maintained that women have fewer teeth than men; although he was twice married, it never occurred to him to verify this statement by examining his wives' mouths.”
Maybe Aristotle miscounted teeth, but his works are filled with brilliant observations. Observing the natural world certainly did occur to him. Richard Dawkins is one of those who believe that Aristotle stunted science. But only because someone told him, and not from any facts.

I defended Aristotle against Kuhnian criticisms last year. I have also posted at great length about how modern theoretical physics like string theory has lost its way because of a failure to connect with pre-existing science. These supposed proposed paradigm shifts and revolutions are usually justified with entirely fallacious analogies to faulty historical accounts of Aristotle, Copernicus, Galileo, and Einstein. We need to get the history correct if it is to be used as an example.

Sunday, December 15, 2013

Modifying space and time

One of the main points of my book, How Einstein Ruined Physics, is that the essence of special relativity is that the electromagnetic covariance is deduced from the spacetime geometry. That is what gives relativity its central importance in physics.

I also argue that Einstein had no role in either discovering or popularizing this crucial idea. He did not even understand it until after many other physicists did.

Briefly, here is the history of special relativity. Maxwell discovered the first relativistic theory, following the work of Gauss, Faraday, and others, and coined the word "relativity". Michelson did the crucial experiment on the relativity of motion, following a suggestion of Maxwell. Lorentz built on Maxwell's theory, and discovered the transformations that reconciled the theory with Michelson's experiments. Poincare perfected Lorentz's work, and discovered the 4-dimensional spacetime geometry and electromagnetic covariance in 1905. Minkowski extended and elaborated Poincare's ideas, emphasizing the geometry, and published the 1908 paper that got everybody excited about relativity.

Einstein played no part in any of this. Historians say that he paid no attention to the relativity experiments that inspired Lorentz, Poincare, and Minkowski, that the main point of his paper was that he postulated what Lorentz had proved, and that the physics community was not impressed by his 1905 paper at the time.

More importantly, Einstein's 1905 paper and subsequent papers lack the crucial concepts of spacetime geometry and electromagnetic covariance. I explain this in my book, and refute scholars who say otherwise.

I neglected to address a comment from a 1905 Einstein private letter where he seems to say that he had a spacetime theory. Noted science writer James Gleick writes about Einstein's 1905 papers:
The name echoes through the language: It doesn't take an Einstein. A poor man's Einstein. He's no Einstein. In this busy century, dominated like no other by science—and exalting, among the human virtues, braininess, IQ, the ideal of pure intelligence -— he stands alone as our emblem of intellectual power. We talk as though humanity could be divided into two groups: Albert Einstein and everybody else.

... Einstein said in a letter to a friend, it "modifies the theory of space and time." Ah, yes. Relativity.
The quote is from a letter to Einstein's friend, Conrad Habicht. Here is a little more context:
Such movement of suspended bodies has actually Been observed by biologists who call it Brownian molecular movement. The fourth work is based on the concepts of electrodynamics of moving bodies and modifies the theory of space and time; ... [quoted in Einstein: the life and times, by Ronald W. Clark, p.87]
He says that his paper is based on electrodynamics. Compare that to what Minkowski said in 1908:
The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.
But Einstein misses all of these points. He fails to say that he has a spacetime theory, that it is a consequence of experiments, that it makes space and time inseparable, and that it is a radical new idea.

Einstein's 1905 paper does give formulas for modifying space and time, but they are the same formulas previously given for the FitzGerald contraction and the Larmor dilation of Lorentz local time. Einstein later acknowledged that he got Lorentz transformations out of the Lorentz 1895 paper, and may have also read subsequent papers on the subject by Lorentz and Poincare.

Some say that Einstein followed experiments, but Clark's biography documents on p.128-130 that Einstein said contradictory things about the Michelson-Morley experiment. Sometimes he said that it was important, and other times he said that it was unimportant or that he never even heard of it. Most Einstein historians now say that he ignored experiments like Michelson-Morley, and that they praise him for using postulates instead. I think that Einstein ignored experiments because he was just reciting Lorentz's theory, and he knew that the experimental evidence would be the same as that for Lorentz's theory. Einstein did not even claim (until years later) that he was doing anything different from Lorentz. Lorentz's approach was very different because he was creating a new theory to explain the experiments.

It sounds as if Einstein was getting close when he says his paper "modifies the theory of space and time", but he is basing it on electrodynamics just as Lorentz did 10 years earlier. Lorentz also modifies space and time with his Lorentz transformations. The core of Lorentz's theory was that the experiments could be explained by coupling motion to changes in space and time. It is silly to assume that Einstein meant something different from Lorentz unless Einstein actually said that he meant something different from Lorentz. He did not, and he was happy to see other physicists call it the "Lorentz-Einstein theory".

If Einstein had said, "I show that a new non-Euclidean geometry of space and time can be used to explain the electrodynamics of moving bodies", then I would have to agree that Einstein understood the essence of special relativity, and that he could be called a co-discoverer of the theory. But he did not. Poincare and Minkowski said it, and everyone else got it from them, and not Einstein. Einstein did not even understand or accept it until after the mainstream European physicists did after 1908.

Thursday, December 12, 2013

Non-local theories violate causality

A new paper by Egg and Esfeld has this abstract:
The paper argues that a causal explanation of the correlated outcomes of EPR-type experiments is desirable and possible. It shows how Bohmian mechanics and the GRW mass density theory offer such an explanation in terms of a non-local common cause.
This is nonsense. A non-local theory is not a causal explanation of anything.

An explanation of how an event A causes an event B means that there is a continuous chain of causes from A to B moving forward in time. A non-local theory is just the opposite, as it posits some sort of action-at-a-distance.

The article says:
There are two principled ways of causally explaining correlations between two distinct events: one can either postulate a direct causal influence of one event on the other or one can suppose that a common cause of the two events accounts for the correlation. In everyday contexts, this distinction is crucial, because it has consequences for the kinds of manipulations that we can perform. If there is a direct causal link from event A to event B, then we can (in principle) bring about changes in B by intervening on A, whereas this is not possible if A and B are only connected via a common cause. In the context of quantum mechanics, however, the distinction between a direct cause (DC) and a common cause (CC) is much more elusive, since we cannot control the outcomes of quantum measurements in the right way to perform the intervention on A that is necessary to distinguish between these two causal structures.

Bohmian mechanics is thus not committed to superluminal causation in an operational sense, but it is so committed in a metaphysical sense: given any initial particle configuration, the theory supports counterfactual claims of the type: “If Alice had chosen a different setting, Bob would have obtained a different outcome”. This might sound like a kind of action at a distance that should be understood in terms of a DC model (see section 2), rather than as the manifestation of a common cause.
I am not why anyone likes a silly theory like Bohmian mechanics, but some people mistakenly believe that it gives a causal interpretation to quantum mechanics. It does not. The ordinarly Copenhagen interpretation is much more compatible with causality than Bohmian mechanics.

Tuesday, December 10, 2013

Russell denies the law of causality

Explanations of quantum mechanics can get very confusing on the subject of causality. It is odd that people get tripped up on such a simple concept. Apparently there is a long history of smart people saying stupid things about causality.

Bertrand Russell wrote in a 1913 essay on causality:
In the following paper I wish, first, to maintain that the word "cause" is so inextricably bound up with misleading associations as to make its complete extrusion from the philosophical vocabulary desirable; secondly, to inquire what principle, if any, is employed in science in place of the supposed "law of causality" which philosophers imagine to be employed; thirdly, to exhibit certain confusions, especially in regard to teleology and determinism, which appear to me to be connected with erroneous notions as to causality.

All philosophers, of every school, imagine that causation is one of the fundamental axioms or postulates of science, yet, oddly enough, in advanced sciences such as gravitational astronomy, the word "cause" never occurs. Dr. James Ward, in his Naturalism and Agnosticism, makes this a ground of complaint against physics: the business of those who wish to ascertain the ultimate truth about the world, he apparently thinks, should be the discovery of causes, yet physics never even seeks them. To me it seems that philosophy ought not to assume such legislative functions, and that the reason why physics has ceased to look for causes is that, in fact, there are no such things. The law of causality, I believe, like much that passes muster among philosophers, is a relic of a bygone age, surviving, like the monarchy, only because it is erroneously supposed to do no harm. ...

We may now sum up our discussion of causality. We found first that the law of causality, as usually stated by philosophers, is false, and is not employed in science. We then considered the nature of scientific laws, and found, instead of stating that one event A is always followed by another event B, they stated functional relations between certain events at certain times,
This is all nonsense. Of course gravitational astronomy speaks of causes, as does all other advanced sciences. It is hard to see how something could be scientific without recognizing causes.

I am trying to understand how people could be so confused about time, causality, determinism, and free will.

Russell appears to believe that determinism is some empirical fact, but it cannot be. Charlotte Werndl shows:
The central question of this paper is: are deterministic and indeterministic descriptions observationally equivalent in the sense that they give the same predictions? I tackle this question for measure-theoretic deterministic systems and stochastic processes, both of which are ubiquitous in science. I first show that for many measure-theoretic deterministic systems there is a stochastic process which is observationally equivalent to the deterministic system. Conversely, I show that for all stochastic processes there is a measure-theoretic deterministic system which is observationally equivalent to the stochastic process.
So some formulation of quantum mechanics may be deterministic or not, but that tells us nothing about whether the real world is.

I don't know why Russell was so opposed to causality, except maybe it is related to his atheism. Leftist-atheist-evolutionist Chris Mooney argues that belief in "teleological thinking" or causality is a major deterrent to people accepting evolution over God.

Monday, December 9, 2013

Kinematics did not distinguish Einstein

Alberto A. Martínez wrote in an article on relativity:
Due to his research on relative motion in optics and electromagnetics, he advanced a series of modifications to the traditional transformations that eventually led to the equations advocated by Larmor, Poincaré, Einstein, and others.8 Hence, Poincaré gave the name ‘‘Lorentz transformations’’ to these new equations, although Woldemar Voigt had published equivalent equations in 1887.9 In 1909 the simpler and older transformation equations were named the ‘‘Galilean transformations’’ by Philipp Frank.10

What distinguished the new transformations in Einstein’s work in comparison to the equivalent equations in the earlier work of other physicists was that Einstein introduced such transformations by means of general kinematic arguments, rather than introducing them exclusively for the solution of problems in optics and electrodynamics.
This is a typical strained effort to credit Einstein, even tho the Lorentz transformations were named after Lorentz before Einstein wrote about them.

The explanation is nonsense. Lorentz devised the transformations to explain the Michelson-Morley experiment and other electromagnetic puzzles. So yes, Michelson-Morley was an experiment on the speed of light, so it was for optics and electrodynamics. Einstein's method was also for optics. After all, the transformations involve the speed of light and he used light throughout his analysis.

Kinematics is a word meaning the study of motion without considering forces. It has nothing to do with whether optics and electrodynamics are used. Einstein believed that he had a conceptual simplification in explaining Lorentz's theory by first describing the consequences when no forces are involved.

But Einstein failed to get to the heart of relativity. Poincare and Minkowski introduced the transformations with non-Euclidean geometry, and that is the preferred method today, and has been since about 1908. That is, they removed the motion and the forces, and made it a theory of spacetime geometry. Then they showed how the motion and forces are affected by the geometry. They were not influenced by Einstein who did not even understand what they did.

Martinez is typical of Einstein idolizing scholars. They know about the work of Lorentz and Poincare, so they are hard-pressed to say that Einstein did anything original. The closest they can come is to mumble something about kinematics, meaning that Einstein took Lorentz's equations and observed that they apply when forces are absent. They try to trick you into believing that this was a step towards the spacetime geometry, but it was not, as Poincare wrote his 1905 paper on the spacetime geometry before Einstein's paper was published.

Friday, December 6, 2013

Lorentz was an honorable man

In response to Equivalence between Lorentz and Einstein, I got this comment:
[ad hominem attack snipped] Lorentz has been quoted from 1905 to his death that Einstein was the sole architect of special relativity. I don't understand what you don't understand about that. Moreover, they were very close friends, another fact that would repudiate your "argument" if you had one other than citing arcane quotes without proper context or citation. Case closed. And special relativity is NOT Einstein's greatest paper. That statement alone invalidates the rest of your hogwash.
It is simply not true that Lorentz credited Einstein with all of special relativity. As quoted on the above post, Lorentz said "Einstein simply postulates what we have deduced". Also, Einstein did not refute Lorentz.

Lorentz and Einstein were not close friends. Lorentz was an honorable man who always scrupulously credited his sources. Einstein was not.

Eisntein's 1905 relativity paper is widely regarded as his greatest paper, if not the greatest physics paper of the 20th century. I agree that the paper was not so great, but I am reciting popular opinion.

Wednesday, December 4, 2013

Einstein was a monster

I just stumbled across a web page on THE EINSTEIN MONSTER:
EINSTEIN THE PLAGIARIST
EINSTEIN THE MISTAKEN
EINSTEIN THE ABUSER
EINSTEIN THE SERIAL ADULTERER
EINSTEIN THE "DEAD BEAT DAD"
EINSTEIN THE ATTENTION WHORE
EINSTEIN THE COMMUNIST
EINSTEIN THE WARMONGER
EINSTEIN THE ANTI-AMERICAN
EINSTEIN THE GLOBALIST
EINSTEIN THE MASS MURDERER
EINSTEIN THE RACE AGITATOR
EINSTEIN THE ZIONIST
I have posted mainly about Einstein's scientific contributions. Yes, he was a plagiarist in the sense that he published the ideas of others, and failed to credit them. Most of his fame is for work that was actually done previously by others.

I am more interested in the science because there are some lessons about how scientific progress happens.

But if you read any of the Einstein biographies, you will see that he was a pretty horrible human being.

Tuesday, December 3, 2013

The word is science

The Merriam-Webster’s Word of the Year is Science. Strange. Did science suddenly become important last year?

The runners-up were: cognitive, rapport, communication, niche, ethic, paradox, visceral, integrity, metaphor.

Monday, December 2, 2013

Irreversible loss of information

Physicist Sean M. Carroll writes:
This year we give thanks for an idea that establishes a direct connection between the concepts of “energy” and “information”: Landauer’s Principle. ...

Landauer’s Principle states that irreversible loss of information — whether it’s erasing a notebook or swiping a computer disk — is necessarily accompanied by an increase in entropy. Charles Bennett puts it in relatively precise terms:
Any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information bearing degrees of freedom of the information processing apparatus or its environment.
The principle captures the broad idea that “information is physical.”
Okay, fine, but various big-shot physicists foolishly insist that information is always preserved. They have to deny information loss in order to argue for many-worlds (MWI) and black hole firewalls.