Friday, August 31, 2012

Questioning scalable quantum computing

The Physics Stack Exchange is a great site for answering physics equations. I mentioned below a famous Nobel prizewinner defending an idea that most physics discard as crazy. Craig Feinstein asks:
See "The Principle of Relativity" here: http://en.wikisource.org/wiki/The_Principles_of_Mathematical_Physics This was written by Poincare in 1904, a year before Einstein published his theory of relativity.

It appears from this and other writings of Poincare that Poincare discovered the theory of special relativity before Einstein. So why does Einstein get the credit?
He also asks:
As far as I know, scalable quantum computing has never been demonstrated either backwards in time or forwards in time. So a fortiori, I would think that this would be good enough evidence to suggest that scalable quantum computing is impossible. Yet, some physicists believe that scalable quantum computing is still possible. Why?
These are two areas where I think that the conventional wisdom is wrong. Check out the site to see how these ideas debated.

Thursday, August 30, 2012

Prejudice against positivism

There is a philosophical prejudice against positivism, as shown by the following story from S. Weinberg's book:
Positivism did harm in other ways that are less well known. There is a famous experiment performed in 1897 by J. J. Thomson, which is generally regarded as the discovery of the electron. (Thomson was Maxwell's and Rayleigh's successor as Cavendish Professor at the University of Cambridge.) For some years physicists had puzzled over the mysterious phenomenon of cathode rays, rays that are emitted when a metal plate in a glass vacuum tube is connected to the negative terminal of a powerful electric battery, and that show their presence through a luminous spot where they strike the far end of the glass tube. The picture tubes in modern television sets are nothing but cathode ray tubes in which the intensity of the rays is controlled by the signals sent out by television stations. When cathode rays were first discovered in the nineteenth century no one at first knew what they were. Then Thomson measured the way the cathode rays are bent by electric and magnetic fields as they pass through the vacuum tube. It turned out that the amount of bending of these rays was consistent with the hypothesis that they are made up of particles that carry a definite quantity of electric charge and a definite quantity of mass, always in the same ratio of mass to charge. Because the mass of these particles turned out to be so much smaller than the masses of atoms, Thomson leapt to the conclusion that these particles are the fundamental constituents of atoms and the carriers of electric charge in all currents of electricity, in wires and atoms as well as in cathode-ray tubes. For this, Thomson regarded himself, and has become universally regarded by historians, as the discoverer of a new form of matter, a particle for which he picked up a name that was already current in the theory of electrolysis: the electron.

Yet the same experiment was done in Berlin at just about the same time by Walter Kaufmann. The main difference between Kaufmann's experiment and Thomson's was that Kaufmann's was better. It yielded a result for the ratio of the electron's charge and mass that today we know was more accurate than Thomson's. Yet Kaufmann is never listed as a discoverer of the electron, because he did not think that he had discovered a new particle. Thomson was working in an English tradition going back to Newton, Dalton, and Prout—a tradition of speculation about atoms and their constituents. But Kaufmann was a positivist; he did not believe that it was the business of physicists to speculate about things that they could not observe. So Kaufmann did not report that he had discovered a new kind of particle, but only that whatever it is that is flowing in a cathode ray, it carries a certain ratio of electric charge to mass.

Weinberg's point is to attack positivism, but he does not mention that Thomson's son, George Paget Thomson, won the 1937 Nobel Prize for proving that the electron was not a particle, but a wave.

A modern equivalent is the dispute over the credit for the Higgs boson. The Higgs mechanism was discovered by Anderson and others, and underlies the Standard Model of particle physics. Maybe a Nobel Prize should have been given for that decades ago, as it seems as important as what Weinberg did to get the 1979 prize. Now that the LHC is confirming the Higgs boson, Higgs is first in line for credit because he was the only one to predict a particle from the mechanism. Maybe they should just give the prize to the LHC for finding the particle.

Here is a recent discussion:

Scott Aaronson: I’d consider [Copenhagen] less an “interpretation” than a decision to treat quantum mechanics instrumentally, and simply not to ask certain questions.

Douglas Knight: That’s rewriting history. Everyone in the 20s, pro or con (except Bohr), agreed that what Bohr said was that consciousness causes collapse.

Scott Aaronson: Could you give me some sources for that?

I’ve read Bohr, and I thought he was perfectly clear in his obscurity! That is, he said again and again that what defined the split between the quantum and classical worlds was not the experimenter’s consciousness, but rather “the very conditions of measurement, by means of which the description of the atomic phenomena is… [blah blah blah]”
Bohr was a positivist. They seem to agree that everyone was persuaded by Bohr about quantum mechanics without anyone understanding the positivist view that he was taking.

Tuesday, August 28, 2012

Ruling out a deeper theory

The author of a hotly-discussed paper explains how it almost got published in Nature magazine:
The theorem we prove – that quantum states cannot be understood as merely lack of knowledge of an underlying deeper reality described by some as yet undiscovered deeper theory – assumes preparation independence. ...

We are in a similar position with Bell’s theorem, which I consider the most important insight into the nature of physical reality of the last century, an honour for which there are some serious competitors! That theorem relies on a presumed ability to make independent choices of measurements at separated locations. Denial of such is the “super-determinism” loophole, ...
I guess the editors took the superdeterminism loophole too seriously. Or maybe they did not like being scooped by a preprint server.

The authors claim to be ruling out an "undiscovered deeper theory", but they really only rule out certain types of theories. Maybe the editor was fooled into thinking that their theorem was stronger than it really is.

I do not agree with the hype over Bell’s theorem or the above paper. Those theorems just affirm the understanding of quantum mechanics that has been the consensus since about 1930. They only get attention because they claim to say something about what "reality" is. Lumo is harsher:
If you read the paper by Pusey, Barrett, and Rudolph, it is self-evident in pretty much every sentence that they always assume that the world is a manifestation of a fundamentally classical system of laws. Even though physicists have known that the laws of physics in this Universe fundamentally differ from the very framework of classical physics for more than 85 years, these folks view the possibility of a non-classical essence of the world as a taboo. It can't even be thought about. A heresy. These folks are typical cultists, religious nuts.

In practice, they only think about several classes of hypothetical classical descriptions; non-classical candidates aren't allowed. In essence, these crackpots assume that the state of the world is fundamentally described either by an "ontic" state (from a Greek world related to the existence of things) – a pompous would-be philosophical term for a point in a phase space – or an "epistemic" state – a fancy word for a probability distribution on a phase space.

These nuts are sometimes capable of finding arguments that one of the scenarios is incompatible with the reality – everyone can do it easily because both scenarios are obviously incompatible with reality – but they incorrectly assume that any evidence against one of these two classical models shows that the other model is right.

But it doesn't because both of them are wrong. The world isn't described by any "ontic" state; and it isn't exactly described by an "epistemic" probability distribution on a phase space, either. It is described by a theory – quantum mechanics – that cleverly generalizes the second possibility.
My FQXi essay was written, in part, as a response to quantum confusions about reality shown by the attention given to the above paper. The authors and many others assume that "deeper reality" means a mathematical model of a certain type. There could be a deeper physical reality that is not so neatly modeled mathematically. That is what I argue in the essay. If you think that I have worthwhile points, please go online and give a rating to the essay, as that will help me get the attention of the judges. The contest submission period is now closing, and there is a period of public discussion about the essays. Dozens of essays have been submitted, and many have far-fetched ideas.

Update: Lumo adds, in his rant against the above paper:
What he doesn't want to show is that even according to the sociological criteria, the paper sucks. Nine months after these folks "shook the foundations of physics", using Eugenie Samuel Scott's modest words, the paper has eleven citations.

The only paper in this list of 11 papers that has been cited itself is a paper by Hardy – which is also deeply confused, by the way. In this list of the other 10 dull, confused, and uncited papers, the most eye-catchy one is the last one, an essay written by hardcore creationist crackpot and a Shmoit fan Roger Schlafly: Nature has no faithful mathematical representation. Although the author is a complete nutcase, this paper is arguably the most sensible one (or least insane one) in the list of the 11 papers (although it brings nothing new, of course).
No, I am not a creationist. By "Shwoit fan", he means a critic of string theory.

Saturday, August 25, 2012

Claiming Poincare believed in true time

LionAxe defends Einstein's prioriy on another forum. I responded to his previous arguments here.

Even if everything he said were correct, and Poincare were a senile old fool who constantly babbled nonsense, believed in astrology, and prayed to Satan, it would not matter to my argument. Poincare published the essential ideas and proofs that turned Lorentz's theory into the modern theory special relativity. Einstein did not even understand those ideas.

Einstein was wrong about many things. Hans Ohanian wrote a whole book on Einstein's Mistakes. Nobody denies Einstein credit because he made mistakes. People get credited for what they do right.

LionAxe says that Poincare believed that electromagnetism requires a non-vacuum medium for wave propagation and that the universe has a preferred frame that defines motion. If so, Poincare was right, because today's physics textbooks say that both of these are correct. Electromagnetic waves are explained by quantum electrodynamics (QED), and that requires a nontrivial vacuum state different from the vacuum. And observations of the cosmic microwave background have shown a preferred frame for motion.

The QED vacuum state (ie, modern aether) is Lorentz invariant. If LionAxe could find a quote showing that Poincare believed otherwise, then I would agree that he said something that was eventually determined to be wrong. However, LionAxe's quotes show that Poincare believed that it was impossible to detect absolute motion, and therefore his ideas were consistent with the modern idea of Lorentz invariance of QED.

As quoted, Poincare explained "the reason why we believe in an aether is simple." Poincare argued that the aether was a useful convention, but not essential. He correctly explains the reasons for the belief. He is correct.

Poincare also explained Lorentz's theory, using Lorentz's terminology. Lorentz explained in 1895 why the evidence was against the aether drag hypothesis, and used the term aether at rest as a shorthand for rejecting that hypothesis. Poincare correctly describes that argument. Einstein avoids the issue because he just postulates Lorentz's conclusions while ignoring the analysis that went into those conclusions (and not citing Lorentz).

The Einstein scholars like to say that Poincare believe in true time, and hence he must have also believed in the aether because only clocks in the aether frame would show the true time. Their proof is Poincare's 1904 St. Louis Worlds Fair lecture where he gives a completely correct description of relativistic time and clock synchronization and then says:
The watches adjusted in that manner do not mark, therefore, the true time; they mark what one may call the local time, so that one of them goes slow on the other.
If Poincare were claiming that were a true time, then he would be consistent with modern cosmology. The leading model, the Lambda-CDM model, does in fact have a true time defining the age of the universe.

But Poincare is not asserting a true time; he is denying one. It is as if I said, "I went camping and I did not see bigfoot", and then someone accused me of believing in bigfoot. It is hard to argue with such illogical nonsense. But defense of Einstein's priority is usually based on reversing the meaning of simple sentences like this. The Einstein scholars adamantly and relentlessly defend the idea that he wrote the most original science paper ever written, but they can never explain what was original about it, or how all the truly original ideas were published by Lorentz and Poincare.

Thursday, August 23, 2012

50 years of paradigm shift theory

John Naughton writes:
Fifty years ago this month, one of the most influential books of the 20th century was published by the University of Chicago Press. Many if not most lay people have probably never heard of its author, Thomas Kuhn, or of his book, The Structure of Scientific Revolutions, but their thinking has almost certainly been influenced by his ideas. The litmus test is whether you've ever heard or used the term "paradigm shift", which is probably the most used – and abused – term in contemporary discussions of organisational change and intellectual progress. ...

Kuhn's encounter with the scientific work of Aristotle turned out to be a life- and career-changing epiphany. ... By the standards of present-day physics, Aristotle looks like an idiot. And yet we know he wasn't. Kuhn's blinding insight came from the sudden realisation that if one is to understand Aristotelian science, one must know about the intellectual tradition within which Aristotle worked. ...

Kuhn's central claim is that a careful study of the history of science reveals that development in any scientific field happens via a series of phases. ...

But what really set the cat among the philosophical pigeons was one implication of Kuhn's account of the process of paradigm change. He argued that competing paradigms are "incommensurable": that is to say, there exists no objective way of assessing their relative merits. There's no way, for example, that one could make a checklist comparing the merits of Newtonian mechanics (which applies to snooker balls and planets but not to anything that goes on inside the atom) and quantum mechanics (which deals with what happens at the sub-atomic level). But if rival paradigms are really incommensurable, then doesn't that imply that scientific revolutions must be based – at least in part – on irrational grounds? In which case, are not the paradigm shifts that we celebrate as great intellectual breakthroughs merely the result of outbreaks of mob psychology? ...

In the meantime, if you're making a list of books to read before you die, Kuhn's masterwork is one.
Read The Structure of Scientific Revolutions to see how professors could deny that science makes progress towards truth. This silly academic book has sold 1.4 million copies, far more than any comparable work.

The concept of incommensurable paradigms is nonsense. Of course it is possible to make a checklist comparing the merits of Newtonian and quantum mechanics.

Kuhn never did explain his supposed Aristotle epiphany. Aristotle did not have a quantitative theory of motion. Kuhn partially explains what he meant, but not completely. I think that he exaggerates to support his dubious paradigm theory.

My only epiphany with Aristotle's physics was in seeing what is wrong with this
answer:
What is the difference between natural motion and violent motion?

This is Aristotelean philosophy and is about 400 years out of date.

Artistotle divided motion into the 'natural' motions and the 'violent' motions. Natural motions were those motions that objects naturally did: objects on earth fell towards the center of the earth. Heavenly objects naturally moved in circles. Violent motion was *anything* other than this. So, to pick up a rock was considered a violent motion.

This view of physics was completely replaced when Issac Newton published his laws of motion in 1687. It had been challenged by Galileo and Kepler in the early 1600's. No physicist today sees Aristotle's views as having any validity whatsoever. They have been thoroughly debunked.
In Newton's view, all acceleration is just response to forces, and there is no distinction between natural and violent.

But Newton's view is not the modern view. According to relativity, gravity is not really a force, and gravitational acceleration is really just natural motion. Technically they are spacetime geodesics. Other kinds of motions are violent in the sense that they are not geodesics. Aristotle's view is actually quite similar to the modern distinction between geodesic and non-geodesic motion.

Before my Aristotelian epiphany, I would have agreed that "No physicist today sees Aristotle's views as having any validity whatsoever." Now I think that he was making a brilliant observation about motion.

Tuesday, August 21, 2012

Big-shot defends superdeterminism

Gerard 't Hooft was the chief theoretical physicist behind the Standard Model, and now he writes:
My recent papers were greeted with scepticism. I've no problem with that. What disturbes me is the general reaction that they are "wrong". my question is summarised as follows:

Did any of these people actually read the work and can anyone tell me where a mistake was made?

Now the details. I can't help being disgusted by the "many world" interpretation, or the Bohm - deBroglie "pilot waves", and even the idea that the quantum world must be non-local is difficult to buy. I want to know what is really going on, and in order to try to get some ideas, I construct some models with various degrees of sophistication.
He believes in determinism, and even superdeterminism, but not quantum computers.

His view is in the minority.

I am inclined to agree with him about many worlds, pilot waves, locality, and quantum computers.

Update: Scott Aaronson comments:
Much like with Godwin’s Law, “superdeterminism” strikes me as the sort of thing that you resort to after you realize you’ve lost an argument.

Look, according to superdeterminism, you’re allowed to say about any experimental result: “well, maybe that happened because of a giant universe-wide conspiracy involving both the particles you measured and the atoms of your own brain—which allowed the particles to know in advance which experiment you were going to do, and to get into just the right state, thereby fooling you into thinking that, had you chosen to do a different experiment (which is actually impossible, since you lack free will), you would’ve continued to see results consistent with standard physical theory. So it all looks like the standard physical theory is valid, but really it’s not.”

With these universe-as-magician rules, I agree that you can “explain” any conceivable scientific discovery. But precisely because of that flexibility, I’d say your victory is a hollow one, devoid of explanatory value.
Of course Aaronson also supports many-worlds and quantum computers. He conceded that quantum computers have not been demonstrated, but says that the burden of proof is on the skeptics to prove that they are impossible.

Monday, August 20, 2012

Copernicanism and many worlds

Scott Aaronson writes:
Proponents of MWI, such as David Deutsch, often argue that MWI is a lot like Copernican astronomy: an exhilarating expansion in our picture of the universe, which follows straightforwardly from Occam’s Razor applied to certain observed facts (the motions of the planets in one case, the double-slit experiment in the other). Yes, many holdouts stubbornly refuse to accept the new picture, but their skepticism says more about sociology than science.
So he supports the Many Worlds Interpretation but reject one of the main arguments for it?

The real problem with MWI is that it hypothesizes zillions of unobservable worlds that add nothing to the theory. Copernicanism does not do that.

The other big problem is that MWI makes probabilities meaningless. Improbable events always happen in some other universe, and we might be living in that other universe.

Aaronson doesn’t see how the laws of quantum mechanics could allow double slits but not quantum computers, but not (super-Turing) quantum computers. And he doesn’t see how the 2nd Amendment could allow a semi-auto rifle but not an ICBM nuke. He offered $100k to prove me wrong.

Deutsch argues that a quantum computer will prove that MWI is correct. If I believed his argument, then that would be another reason to doubt quantum computers.

I agree with this comment:
MWI is the most absurd thing ever to come out of science.

It’s as extreme a violation of the Occam razor principle (entities should not be multiplied without necessity) as possible. I challenge anyone to try to come up with something that would violate it more. The most incredible thing about it is that it doesn’t offer even a single practical benefit over other interpretations like the truly minimalist statistical/ensemble interpretation.

Only physicists can be so arrogant as to postulate billions onto billions of even in principle unobservable universes just to make their theory a bit nicer in mathematical terms, or to avoid having to admit to their own ignorance.
I don't think that MWI makes the theory nicer. It only does so if you believe that the wave function is a true and faithful representation of reality, and probability is conserved via unitarity, and mathematical realities are also physical realities. But I do not believe in any of those things, as you can see from my FQXi essay.

Aaronson responds that there are many more absurd ArXiv papers. Yes, but MWI has a mainstream following and those papers do not.

Update: Aaronson adds:
If the Hilbert space is finite-dimensional, then certainly the number of “universes” will also be finite. And there are indications today—specifically, from the dark energy together with the holographic principle—that the total Hilbert space accessible to any one observer has a “mere” ~e10^123 dimensions. So as long as you only care what happens inside our causal horizon, you should be able to get away with only finitely many universes! If you also want to include what happens outside our causal horizon, then the answer would depend on whether the universe is spatially infinite or not, which no one knows (or possibly will ever know). But notice that, if the universe is spatially infinite, then you already have infinity even without MWI! In that case, MWI would “merely” take you up from Aleph0 to 2Aleph0.

Bottom line, if within each world you take there to be ~S independent degrees of freedom, then you should expect ~exp(S) possible worlds.
Do you believe that MWI allows for so-called “nighmare states” to exist? That is, states where extremely low probability (and potentially awful) phenomena are occuring.

For example, one might unluckily inhabit a universe where all people have survived to the age of 3000, but have aged very badly. Or where everyone has a cellphone with MC Hammer’s “You Can’t Touch This” as an obnoxiously loud ringtone. And I suppose more awful states might exist too.

The existence of such strange and awful states has always made MWI seem somewhat unattractive to me.
If you believe MWI, then it’s straightforwardly true that there would exist such “nightmare states” … as well as utopian dream states and everything in between. From an MWI standpoint, the question is not about the “existence” of these states but only about their relative probabilities.
Seems crazy to me, but he is the MIT professor.

Update: Lumo posts a rant against Aaronson and many-worlds:
The MWI chapter of The Hidden Reality by Brian Greene (whose Czech translation by me will be in the bookstores on Monday) really drove me up the wall many times because most of it is literally upside down. One repeatedly "learns" that if we want to describe the whole world in a uniform fashion, we must adopt the MWI ideology. Bohr et al. were incapable of doing so, so they preferred to live in their messy, marginally inconsistent system of ideas, and use behind-the-scene tricks to fight against the true messengers of the truth such as Hugh Everett III.

This uses the right words except that the content is exactly the opposite of the truth. ...

The primary reason is that quantum mechanics just isn't describing the objects themselves. It describes propositions we can make about objects. As Niels Bohr used to say, Physics is not a tool to describe how the reality is. Physics is a tool to say right things about what we can see. The basic building blocks such as the wave functions and projection operators don't describe and count objects but encode propositions, knowledge, information. ...

Is that really so hard to understand that the wave function in quantum mechanics is a generalization of a probability distribution – and not a generalization of a classical field? It encodes the information about the physical system, not the shape of the object itself. It is not really difficult to learn these things but some people just don't want to.

Friday, August 17, 2012

Relativity and corresponding states

I describe the main technical difference between Lorentz's and Einstein's approach to special relativity.

In 1895, Lorentz published his proof of his "theorem of corresponding states". The purpose was to explain how Michelson observed the same speed of light in different frames of reference. He extended it to massive particles in 1899, and to velocities close to light in 1904.

To explain this, here is the notation. For a stationary frame, use position (x,y,z), time t, electric and magnetic fields (E,B). These satisfy Maxwell's equations.

Theorem. (Lorentz) For a moving frame, there exists a transformation of (x,y,z,t,E,B) into new variables (x',y',z',t',E',B') that satisfy Maxwell's equations and explain the Michelson-Morley experiment.

His statement is a little more complicated because he also considered charged particles, densities, and currents. The theory is called "corresponding states" because the Lorentz transformations define a correspondence between the stationary and moving frame variables. Einstein converted Lorentz's theorem into a postulate:

Postulate. (Einstein, 1905) Let (x',y',z',t',E',B') be the variables for a moving frame. Assume that they satisfy Maxwell's equations, just like (x,y,z,t,E,B).

From this, Einstein deduces that (x,y,z,t,E,B) and (x',y',z',t',E',B') correspond according to the definitions and formulas that Lorentz and Poincare found earlier.

Einstein calls this the principle of relativity, following Poincare's terminology without mentioning him. Einstein describes it as the same laws holding good in different frames. What he actually uses in his famous 1905 paper is the above postulate. That paper said:
They suggest rather that, as has already been shown to the first order of small quantities, the same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good.
Without mentioning Lorentz, Einstein is referring to Lorentz's 1895 theorem of corresponding states, without recognizing the 1904 improvement to high velocities.

Poincare often stated the relativity principle as an observer being unable to detect uniform motion. He was alone in discovering a profound geometrical realization of it.

Theorem (Poincare, 1905) There is a non-Euclidean geometrical interpretation of (x,y,z,t) and Maxwell's equations such that the above transformations are simple consequences of the geometry.

A recent pro-Einstein book said, "But, of course, Einstein at first didn't completely understand the worldview that came from the special theory of relativity.". Einstein did not understand that non-Euclidean geometrical interpretation until several years later. Poincare published it first, then Minkowski got it from Poincare, and other leading physicists got it from Minkowski.

The difference here is that Lorentz and Poincare were giving new results and proving them. Einstein was just taking what Lorentz had proved, and restating it as a postulate. Lorentz said that Einstein simply postulates what we have deduced. Poincare's view became the modern view.

Proving scientific results based on previous theory and experiment is consistent with philosophical positivism. The philosophers and Einstein scholars say that Einstein was anti-positivist because he ignored the previous work and just postulated what he thought ought to be correct. But as you can see, he did not ignore the previous work. He accepted the conclusions while ignoring some of the reasoning behind them. And he did not reach the essence of the theory.

Wednesday, August 15, 2012

Einstein defender misunderstands theory

On another forum, LionAxe writes:
For the hundreth time; he [Poincaré] did not express particle motion in terms of a worldline, or define proper time as a worldline parameter. So inasmuch as spacetime geometry includes worldlines and proper time, Poincaré did not discover spacetime geometry (he left that to Minkowski, and later Poincaré chose a different type of space-time than his).

Most obviously, Poincaré's views on favouring Galileo space-time is found in his "Espace et temps" lecture, reprinted in the collection Dernieres pensees (1913). There, as contained in much of his other work, Poincare considered that space and time are defined by the symmetry group of classical mechanics. And... the symmetry group of classical mechanics is the Galilei group. Consequently, Poincare used the Galilei group to define space and time, he then interpreted the space and time coordinates entering the Lorentz transformation in terms of an immobile ether, assumed to be at rest with respect to absolute space, regarding more or less all of this as conventions (whereas Einstein denied, for example, Lorance covariance to be conventional).
I don't know how anyone could be so mixed up about relativity. One the core concepts of relativity is the Lorentz group. Poincared discovered it in 1905, and named it. It is very commonly used today, with Poincare's terminology. It is the group of symmetries of spacetime, and is distinctly different from the Galileo group. The Lorentz group is for when all speeds are limited by the speed of light, as in relativity. The Galileo group has no such limit.

LionAxe is trying to deny that Poincare had the Lorentz group, I guess. But everyone agrees that it came from Poincare's 1905 paper. Einstein did not have it. LionAxe also argues that Poincare had a privileged frame. But the Lorentz group proves that there is no privileged frame. Einstein had no such proof. Poincare's there never had any dependence on a privileged frame or aether.

LionAxe's comments about geometry are also nonsense. The special relativity geometry came from Poincare and Einstein had no part in it.

Some related claims of LionAxe are rebutted by Bjerknes.

Poincare published his principle of relativity, and his theory that the Lorentz group provided symmetries making each frame the same as any other. Poincare's papers on this were widely circulated, well-known, and available to Einstein before he every wrote a word on the subject. Any statement that Poincare had a preferred inertial frame shows LionAxe's misunderstanding of the most basic aspects of relativity.

Einstein's 1905 paper failed to show that the frames were equivalent. He spent his whole life claiming that he never read or knew about Poincare's papers. The only reasonable conclusion is that Einstein tried to steal Poincare's ideas, Einstein failed to understand the core of relativity in Poincare's 1905 paper, and Einstein lied about it all his life. The Einstein scholars hate to admit this, but they cannot refute it.

It is funny how some people will persist in the most ridiculous arguments to defend Einstein. There is no reasoning with him. He keeps saying that Poincare was wrong about things but he cannot find a single quote that was wrong. He keeps saying that Einstein's work was original, but he cannot point to one original aspect to his work.

Update: Poincare certainly did introduce in 1905 the spacetime geometry as we know it today. I say this because (1) he combined space and time into a 4-dimensional spacetime, (2) he defined the metric, now known as the Minkowski metric, (3) he formulated the Lorentz group (and not any Galilean group) as the symmetries of spacetime, (4) his relativity was a spacetime theory that was applicable to electromagnetism as well as any other forces, and (5) he proved that the electromagnetism equations were covariant with respect to the spacetime geometry. These 5 concepts form the core of what modern textbooks teach as relativistic geometry. Poincare had them all in 1905, and Einstein had none of them.

Einstein did not plagiarize this. He did not even understand it. The Einstein book just reviewed in the NY Times said, "But, of course, Einstein at first didn't completely understand the worldview that came from the special theory of relativity." There is no serious dispute about this. The historians sometimes credit the geometric worldview to Minkowski, but it is all in Poincare's 1905 paper, and Minkowski got it from Poincare.

Update: I should probably mention that the above discussion is at a site called a hate site by a racist hate group called the SPLC. The SPLC complains that racial epithets are not always censored. The SPLC was recently in the news for its role in instigating violence against a pro-family organization. All of this is way off-topic for this blog. I was just discussing Einstein's contributions to relativity, and I do not agree with any censorship of that topic.

Friday, August 10, 2012

Tensors in relativity

A couple of Italians posted On the relativistic unification of electricity and magnetism, a few months ago.
On the relativistic unification of electricity and magnetism

The unification of electricity and magnetism achieved by special relativity has remained for decades a model of unification in theoretical physics. We discuss the way the four main relevant authors (Lorentz, Poincaré, Einstein, Minkowski) dealt with this issue and show that Poincaré's derivation of the transformation laws for the potentials and the fields was definitely less arbitrary than those of the other cited authors, in contrast with the fact that here, as in other cases, Poincaré's contribution to relativity was systematically belittled by authoritative German physicists in the first two decades. In the course of the historical analysis a number of questions which are of contemporary foundational interest concerning relativistic electromagnetism are are also examined.

The culmination of special relativity theory was the Lorentz covariance of the electromagnetic field tensor. This was proved by Poincare in his long 1905 paper and popularized by Minkowski in this famous 1908 paper.

This paper explains the details. In particular, it shows how Poincare proved it, how Minkowski got it from Poincare, how Minkowski was stingy about crediting Poincare, and how Einstein did not have the concept at all, or even anything on that level.

This was the biggest relativity breakthru in 1905. None of the Einstein books even mention it, except for my book.

The word tensor was coined in 1898 by Voigt. The first decent mathematical treatment of the concept (without using the word) was by the Italians Ricci and Levi-Civita in 1901. The above paper says:

Poincaré does not refer to the concept of a tensor and does notuse the absolute calculus introduced by Ricci-Curbastro following a remark, by Christoffel, and devel- oped together with his pupil, Levi-Civita ([45]). This is particularly intriguing, since in the preface of their joint work they stressed the value of the tensor formalism citing Poincaré himself, who had written that “a good notation has the same philosophical importance as a good classification in the natural sciences”. However there is only a linguistic divide between what Poincaré does in his paper and the formal recognition that the electric and magnetic fields have been proven to be ‘parts’ of a double tensor in 4-dimensional space. Notice that in contrast to Lorentz’s style, Poincaré does not use the vector formalism either (he always deals with components), so on the same ground one might suggest that he ignores vectors as well, which is obviously absurd.15 What is missing in his treatment, with respect to what Minkowski will do, is the use of 4-dimensional differential operators to reformulate the Maxwell equations.
I did not know that 1901 Ricci-Levi-Civita paper credited Poincare, and I did not know that Poincare had written anything about the concept.

Poincare's long 1905 paper does not define a tensor or say that the electromagnetic field is a tensor. What he does say is that the field is the exterior derivative of a spacetime 4-vector, whose components transform according to Lorentz transformation. This is essentially the same as saying that the field is a tensor.

Grossmann explained tensors to Einstein, and they used the term in their joint 1913 paper. Einstein still did not fully accept the concept, and wrote papers against tensors with his fallacious hole argument. Levi-Civita and Hilbert eventually convinced him of tensors, and his famous 1916 general relativity paper relied heavily on tensors.

Most historians do not agree with me about how relativity credit should be distributed. They are entitled to their opinions, of course. But if they credit Einstein for everything, look to see what they say about electromagnetic covariance. If they don't mention it, then they are not telling you the whole story. If they mention it, look to see where and when Poincare had the concept, and where and when Einstein had it. They usually just talk about Einstein having the concept of Lorentz transformations in 1905, but of course the transofrmations are named after Lorentz because he had them earlier.

Wednesday, August 8, 2012

Physics in the fin-de-siecle Era

Respected Danish historian Helge Kragh writes A Sense of Crisis: Physics in the fin-de-siecle Era
In a textbook of 1902, Albert Michelson, America’s first Nobel laureate in physics, looked forward to the near future when all physical phenomena would be unified under a single theoretical framework. His optimism was rooted in “one of the grandest generalizations of modern science … that all phenomena of the physical universe are only different manifestations of the various modes of motion of one all-pervading substance – the ether” (Kragh 1999: 4). ...

Or, as the distinguished theoretical physicist Joseph Larmor declared in his Aether and Matter published in 1900: “Matter may be and likely is a structure in the ‘aether’, but certainly aether is not a structure of matter” (p. vi; Noakes 2005: 422). ...

At any rate, the demise of the vortex atom did in no way signal the demise of the ether. At the beginning of the new century the ether was much alive, believed to be as necessary as ever. ...

As mentioned, the Zeitgeist of the fin-de-siècle physical sciences included a strong dose of anti-materialism, a desire to do away with brute matter and replace it with either energy or an ethereal medium. The demise of the mechanical ether models was followed by the emergence of a vigorous research program in which the ether was described by Maxwell’s field theory of electromagnetism.
I did not know about this pre-relativistic 4th dimension:
The English-American mathematician and author Charles Howard Hinton wrote a series of articles and books, including The Fourth Dimension of 1904, in which he claimed that the extra space dimension might explain physical phenomena such as the nature of ether and electricity. He suggested that the three-dimensional mechanical ether formed a smooth sheet in the fourth dimension, the thickness of the sheet being approximately that of “the ultimate particles of matter.” Among the few scientists of distinction who entertained similar ideas was the American astronomer Simon Newcomb, who in 1896 uncommittedly speculated that “Perhaps the phenomena of radiation and electricity may yet be explained by vibration in a fourth dimension” (Beichler 1988: 212).

Although hyperspace models of the ether and similar speculations of a fourth dimension were well known in the fin-de-siècle period, they were peripheral to mainstream developments in physics, such as the turn from mechanics to electrodynamics. The fourth dimension caught the public imagination, was eagerly adopted by occultists and idealist philosophers, and became an important utopian theme in literature and art in the early twentieth century (Henderson 2009). Most physicists considered it a harmless speculation of no scientific use.
Maybe it was harmless speculation then, but that is not too far wrong. The preferred explanation of electromagnetism today is that of an invisible extra dimension. See this for details.
The two pillars of this revolution – what today is recognized at the beginning of modern physics – were Planck’s quantum theory of 1900 and Einstein’s theory of special relativity dating from 1905. Both theories stood apart from the fashionable theories of the time based on ether, energy, and electrodynamics. Einstein’s theory operated with four dimensions, but these were quite different from the earlier hyperspace speculations: in relativity theory it is spacetime and not space that has four dimensions. With the recognition of the theories of quanta and relativity the ethereal world view so characteristic of fin-de-siècle physics became obsolete. Einstein summarily dismissed the ether as an unnecessary construct, and the new theory of quanta proved incompatible with the electrodynamic ether embraced by avant-garde physicists.
Just why do those revolutionary theories stand apart? 19th century thermodynamics and electromagnetism seem just as modern to me. Those theories are no more mechanical than 20th century theories.

Monday, August 6, 2012

Einstein’s Jewish Science

George Johnson writes a NY Times book review:
“Jewish physics.” With Einstein’s theories now at the bedrock of modern science, the Nazi’s words have been justly forgotten. It seems almost perverse that Steven Gimbel, the chairman of the philosophy department at Gettysburg College, would want to bring back the old epithet and give it another spin. In his original new book, “Einstein’s Jewish Science: Physics at the Intersection of Politics and Religion,” he considers the possibility that the Nazis were on to something. If you can look past the anti-Semitism, he proposes, “maybe relativity is ‘Jewish science’ after all.” What he means is that there might have been elements of Jewish thinking that gave rise to what is now recognized as one of the deepest insights of all time. ...

What gives Einstein’s work a Jewish flavor, Gimbel believes, is an approach to the universe that reminds him of the way a Talmudic scholar seeks to understand God’s truth. It comes only in glimpses. ...

“The heart of the Talmudic view is that there is an absolute truth, but this truth is not directly and completely available to us,” Gimbel writes. “It turns out that exactly the same style of thinking occurs in the relativity theory and in some of Einstein’s other research.”

From our blinkered perspective we see qualities called space and time. But in relativity theory, the two can be combined mathematically into something more fundamental: a four-dimensional abstraction called the space-time interval. Time and space vary according to the motion of the observer.
The trouble with this view is that Poincare was the one to put space and time together into a four-dimensional space-time in 1905, and Einstein did not even understand or accept it until Minkowski made Poincare's theory popular in 1908.

Wikipedia says:
The leading theoretician of the Deutsche Physik type of movement was Rudolf Tomaschek who had re-edited the famous physics textbook Grimsehl's Lehrbuch der Physik. In that book, which consists of several volumes, the Lorentz transformation was accepted as well as quantum theory. However, Einstein's interpretation of the Lorentz transformation was not mentioned, and also Einstein's name was completely ignored.
The term "Lorentz transformation" was Poincare's 1905 terminology, and his interpretation was that the transformations formed a symmetry group of space-time, with Maxwell's equations for electromagnetism being covariant. Poincare's interpretation is the one popular one today, not Einstein's. So the German physics book could have described relativity accurately.

Gimbel quotes Einstein repeatedly:
Jews are a group of people unto themselves. You can see their Jewishness in their physical appearance and notice their Jewish heritage in their intellectual work and perceive a profound connection between their nature and the numerous interpretations they give to that which they think and feel in in the same way. [p.4,69; alternate translation]

Any analysis of how Einstein's relativity work might be Jewish science must be based on what Einstein actually contributed to special relativity. The consensus among historians is that Einstein ignored experiments like Michelson-Morley, and that he had no new formulas or testable ideas. Einstein is usually praised for obscure terminological differences that have no physical significance. For example, Einstein if praised for not using terms like "local time" or "aether", but no one has ever been able to explain why Einstein's terms like "stationary system" are any better.

My view of science is that it is based on experimental truths, and that advances in science should have some demonstrable superiority to previous knowledge. Those who idolize Einstein have a paradigm shift view where great science is when some hero makes some profound pronouncement based on what he thinks ought to represent some enlightened truth, even tho it is not better in any measurable way. T. Kuhn said that the paradigm shifts are incommensurable.

So was Einstein's view a Talmudic view? I cannot answer that, but I certainly think that it was legitimate for some German physicists to insist on hard evidence to back up theories.

Gimbel makes some analogies between Einstein and Freud, who was also a “secular Jew”, identified with the Jews, and had a Jewish influence on his work. I don’t know how this analogy helps Einstein. Freud was a crackpot who never did any scientific work.

Gimbel acknowledges:

Bjerknes traces elements of the theory of relativity to Lorentz and Poincare, figures we know influenced Einstein's thoughts, as well as Woldemar Voight [sic, Voigt] ... Einstein regularly fails to cite those who influenced his thought and his works, something that is definitely a scholarly no-no. ...

With respect to the special theory of relativity, Bjerknes undertakes the task of showing that each element was presented by someone somewhere before Einstein's 1905 paper. His line is that you do not deserve credit for making the salad if you did not grow the lettuce and pick the tomatoes yourself. ...

The phrase "Copernican Revolution" has come to mean a radical shift in worldview. What Copernicus did was not to invent the sun-centered picture of the solar system but rather to express it in away that make us see the world around us in a different way. ...

But, of course, Einstein at first didn't completely understand the worldview that came from the special theory of relativity. It was Minkowski's geometric interpretation of the theory that took us to the next step. [p.201-202]
The flaw in Gimbel's argument is that Poincare had it all in 1905, including the geometric interpretation that Einstein did not even understand until years later. Someone who buys lettuce and tomato and makes a salad has made something new. Einstein did not make anything new or take us to the next step.

I say that Poincare had the geometric interpretation in 1905 because he had the 4-dimensional spacetime, the Minkowski metric, the Lorentz group of transformations preserving the metric, and the covariance of electromagnetic variables and equations. These concepts are the core of the geometric view, and Einstein had none of it.

One dictionary defines Talmudic as:
characterized by or making extremely fine distinctions; overly detailed or subtle; hairsplitting.
I don't doubt that the Talmud makes sense to those who study it. But to non-Jews, it is just an old obscure book of incomprehensible rules. The only analogy I see here is that you have to make some meaningless hairsplitting distinctions to give credit to Einstein.

It is curious that Gimbel mentions the phrase "Copernican Revolution", a phrase that Kuhn popularized for paradigm shifts. Poincare's long 1905 paper explicitly makes the analogy. It says that Lorentz is to Poincare as Ptolemy is to Copernicus. Thus Poincare boldly declared a new view. Einstein could not explain how his view differed from Lorentz's.

For full disclosure, I should mention that Gimbel has several pages criticizing the Conservapedia Counterexamples to Relativity, where my brother is an editor. I think that the list would be better called paradoxes and anomalies.

Sunday, August 5, 2012

New physics prize

There is a new $3M prize:
The nine are recipients of the Fundamental Physics Prize, established by Yuri Milner, a Russian physics student who dropped out of graduate school in 1989 and later earned billions investing in Internet companies like Facebook and Groupon. ...

Unlike the Nobel in physics, the Fundamental Physics Prize can be awarded to scientists whose ideas have not yet been verified by experiments, which often occurs decades later.
One of the big frustrations of string theorists is that none of them are ever going to get Nobel prizes, because they have no hope of experimental confirmation. So this prize explicitly targets revered scientific geniuses who do not do scientific work.

This is now the biggest prize in physics. Physics has lost its way. For more details, read How Einstein Ruined Physics.

Friday, August 3, 2012

What the Bleep Do We Know

Physics philosopher David Z Albert talks to cosmologist Sean M. Carroll in this 2008 Bloggingheads interview. They defend string theory as legitimate science, even tho they concede that a particle accelerator the size of the galaxy might be unable to test the theory. That is, there is no conceivable observation that would be contrary to the theory.

Nevertheless Albert argues that gravitation is a "spectactular predictive success of string theory."

This is nonsense, of course. If string theory said anything about gravity, then it would be testable. Gravitation is well understood, but there are some anomalies such as dark matter and dark energy. String theory does not resolve these, as one would expect if it really predicted gravity. String theory does not predict gravity.

The only connection between string theory and gravity is that string theory predicts a spin-2 particle, and gravity waves have characteristics of a spin-2 field. But gravity waves have never been observed, and there is no hope of observing those spin-2 gravitons. Also, string theory models are usually assumed to be Ricci-flat, as general relativity requires of empty space.

A recent SciAm article claimed that unitarity and supersymmetric gravity could be used to show that a spin-2 graviton resembles two spin-1 gluons, ressurecting ideas that had been abandoned in the 1980s as unworkable. There are fewer divergences that previous thought, the article says. But there are still infinities that prevent predictions.

They go on to discuss the arrow of time. But there are no testable ideas there either.

Albert also discusses being sucked into the 2004 movie What the Bleep Do We Know!?. He claims that his views were misrepresented. The movie is New Age drivel about quantum consciousness. Of course his ideas were misrepresented. They always are. Physicists themselves cannot express themselves coherently on this subject. Philosophers never say that their views are accurately represented. I have listened to him for a couple of hours, and I still don't think that I could summarize his views in a way that he would accept.

Albert said that physicist Eugene Wigner once said that a dog could make a quantum observation, but not a rat, because dogs are more conscious. Wigner was brilliant and one of the creators of quantum mechanics. If physicists say stuff like this, then they should not be surprised that New Age hippies go further.

Albert previously trashed Krauss's book on nothing, and so Krauss badmouthed all philosophers. Albert was supposed to be one of those philosophers who actually understands physics. They both understand physics but they also say some wacky things.