Tuesday, December 31, 2013

Site compares Poincare to Einstein

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







A separate post says:



Craig writes:




Wednesday, December 25, 2013

Dilbert cat in a box

Today's Dilbert carton is on Schrödinger's cat:
207819.strip - Dilbert Copenhagen cat

Plain English arguments for quantum computers




Monday, December 23, 2013

Silly use of uncertainty metaphor






Lumo rants:


Bohr and Heisenberg both had the properties of




Saturday, December 21, 2013

More evidence against SUSY

Here is the evidency against supersymmetry (SUSY):

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




Thursday, December 19, 2013

Grossmann's contribution to relativity

Grossmann's contribution to the Entwurf theory consisted in the following.








Tuesday, December 17, 2013

Rovelli defends Aristotle

Physicist Carlo Rovelli has just written an excellent summary of Aristotle's physics






and this:


Sunday, December 15, 2013

Modifying space and time












Thursday, December 12, 2013

Non-local theories violate causality

A new paper by Egg and Esfeld has this abstract:


The article says:


Tuesday, December 10, 2013

Russell denies the law of causality


Bertrand Russell wrote in a 1913 essay on causality:






Monday, December 9, 2013

Kinematics did not distinguish Einstein

Alberto A. Martínez wrote in an article on relativity:






Friday, December 6, 2013

Lorentz was an honorable man




Wednesday, December 4, 2013

Einstein was a monster

I just stumbled across a web page on THE EINSTEIN MONSTER:



Tuesday, December 3, 2013

The word is science



Monday, December 2, 2013

Irreversible loss of information

Physicist Sean M. Carroll writes:


Wednesday, November 27, 2013

Dutch reception of relativity

A new Dutch paper on The reception of relativity in the Netherlands says:
This article reviews the early academic and public reception of Albert Einstein's theory of relativity in the Netherlands, particularly after Arthur Eddington's eclipse experiments of 1919. Initially, not much attention was given to relativity, as it did not seem an improvement over Hendrik A. Lorentz' work.
Hardly anyone anywhere saw Einstein's 1905 relativity theory as a significant improvement over Lorentz's previous relativity theory. The theories had the same assumptions, formulas, and consequences.

Excitement about (special) relativity spread dramatically in 1908 with publication of the Poincare-Minkowski non-Euclidean geometry theory of relativity. Then the Lorentz-Einstein view became obsolete. In just a couple of more years, relativity textbooks were being written based on the geometry view.

Monday, November 25, 2013

A skeptical view of black holes

A reader writes:
I am skeptical about black holes, because they involve infinity. There is an opinion that they don't actually solve Einstein's equations.
There is a lot of evidence for black holes, where they are defined:
Belief in such objects dates back two centuries, and has little to do with relativity. If the mass is sufficiently concentrated, the gravity will be sufficiently strong to contain light.

Relativity teaches that the black hole has a boundary, called the event horizon or Schwarzschild radius, and a singularity at the middle. Furthermore, nothing inside the event horizon is observable to anyone on the outside. In particular, the singularity is not observable.

Physics has other infinities that are not observable. For example, the electron is widely assumed to be a point particle, in which case it has infinite density, and the charge concentration gives it infinite energy. These infinities are not observable, and the usual explanation is QED renormalization.

Getting back to my reader's comment, does a rational skeptic really need to believe in physical infinities that can never be observed? I say no. I believe in black holes right up to that event horizon. Discussion of what happens inside the event horizon is just metaphysical fluff that is outside the scope of science. You can say anything you want, and no one can ever prove you right or wrong. Not even in principle, according to relativity.

Likewise, there is no real reason for anyone to believe in the electron infinities. The infinity renormalization schemes may be the most convenient way to calculate electron scattering, but there could well be new physics on other scales to prevent the infinities, such as string theory. As long as the infinities are not observable and not truly required by the theory, there is no reason anyone has to believe in them.

Sunday, November 24, 2013

Sentient life is a freak phenomenon

Arizona State physicist Paul Davies
No, Drake said in 1961 that there could be millions of civilizations in our galaxy. The evidence and arguments for extraterrestial life have not increased much in the last 50 years.

I also don't agree with his reasoning that microbes may be improbable, but if there are microbes then they probably evolve into sentient life. My hunch is that the reverse. I think that it is plausible that microbes are common in our galaxy, but that they have not evolved into sentient life anywhere but Earth.

Life started fairly early in the history of the Earth, but we have no idea how it happened. Maybe it was a freak event, or maybe it would have happened on any similar planet.

We know a lot about the evolution of life on Earth, and intelligent life is a byproduct of a long list of freak accidents. It seems very unlikely to me that all those accidents would be replicated elsewhere in the galaxy.

Update: In the 1980 Cosmos TV series, Carl Sagan also used the Drake equation to estimate millions of advanced civilizations in our galaxy.

Friday, November 22, 2013

Sluggishly expanding wave function

Leftist-atheist-evolutionist Jerry Coyne attacks Deepak Chopra for saying things like these:


See also Coyne's blog, here and here.

I might agree with Coyne that this is unscientific "woo", except that it is not too different from goofy interpretations of quantum mechanics espoused by big-shot physicists.

For a more sane view, Federico Laudisa writes Non-Local Realistic Theories and the Scope of the Bell Theorem:
That's right, there is no proof that either locality or realism is wrong. Those who say otherwise sound just like Deepak Chopra to me.

A new paper, An Introduction to QBism with an Application to the Locality of Quantum Mechanics, by Christopher A. Fuchs, N. David Mermin, Ruediger Schack, explains:
We give an introduction to the QBist interpretation of quantum mechanics. We note that it removes the paradoxes, conundra, and pseudo-problems that have plagued quantum foundations for the past nine decades. As an example, we show in detail how it eliminates quantum "nonlocality".
They act as if they have something new, but they admit that their interpretation is essentially the same as Bohr's, and so all of those problems were solved by the Copenhagen interpretation decades ago.

It is a consequence of the Schroedinger equation that the wave function of the Moon, or of an electron, is indeed a sluggishly expanding wave function in a superposition of possibilities. But electrons and moons are never observed to sluggishly expand. The obvious conclusion is that the electrons and moons are real, but the wave function is a description of our knowledge of their states. That is, my interpretation is epistemic, not ontic. You can believe in that sluggish expansion if you wish, but if you take the wave function too seriously, you can reach some faulty conclusions.

I say that the possibility of quantum computing is an open question, but my personal belief is that it will be impossible for these reasons:

1. The argument for quantum computing is not based on any proven properties of quantum mechanics, but on our inability to simulate quantum systems efficiently in a Turing machine.

2. A lot of smart people have spent a lot of money over decades to demonstrate some super-Turing computing, and no one has succeeded, in spite of recent claims.

3. The computational complexity implications would be sufficiently surprising and contrary to conventional wisdom that claims about a quantum computer should be met with the same extreme skepticism as claims of faster-than-light communication.

4. Quantum computing is an attempt to take advantage of quantum nonlocality, but there is no such thing.

5. Quantum computing requires an interpretation similar to Chopra saying that the Moon is "just a sluggishly expanding wave function in a superposition of possibilities." That sluggish superposition exists in the mind, and it is implausible that it can be used for useful computation.

Other sensible people disagree, such as Scott Aaronson betting that I am wrong. So far, no Nobel prizes have been awarded for quantum computing.

Update: Steven Salzberg piles on:
Chopra’s claim that photons have consciousness, I have to say, is the purest nonsense. Does Chopra even know what a photon is? ... So both photons and the entire planet are conscious. I can see why Coyne called this psychobabble.

Wednesday, November 20, 2013

Science doesn’t explain everything






Monday, November 18, 2013

Lorentz explained the physics

A reader refers to Einstein historians Isaacson and Holton, and writes:
Just read Lorentz's 1895 paper where he explicitly uses those equations to explain the Michelson-Morley experiment (MMX) and other experiments.

The consensus of physics textbooks is that the MMX was the crucial experiment for special relativity. Those Einstein historians say that Einstein was not influenced by the MMX and may not have even known about it.

When Lorentz, Poincare, and Minkowski argued for the correctness of the Lorentz transformations, they all cited the MMX. When Einstein wrote his first paper on the subject in 1905, he did not specifically mention the MMX. Einstein did write a 1909 survey paper where he credited Lorentz with using the Lorentz transformations to explain MMX.

Thus Lorentz's special relativity was certainly not a purely mathematical formulation with no actual physical reference. He explained the physics much better than Einstein, and did it 10 years earlier. Among those who credit Einstein, it is largely for giving an alternative mathematical derivation of the Lorentz transformation, and avoiding the physics.

Those who credit Einstein must somehow explain the undisputed fact that Lorentz and Poincare had published all the equations for special relativity before Einstein. So they make silly arguments about how Lorentz and Poincare did not understand what they were doing, or that "Lorentz and Einstein were great friends", or that anyone who does not recognize that "Einstein is the greatest mind of the 20th century" must be "some kind of neo-nazi or anti-semite".

The reader asks:
Einstein is the one who did not. The Wikipedia article on black hole explains:
Considering the exotic nature of black holes, it may be natural to question if such bizarre objects could exist in nature or to suggest that they are merely pathological solutions to Einstein's equations. Einstein himself wrongly thought that black holes would not form, because he held that the angular momentum of collapsing particles would stabilize their motion at some radius.[70] This led the general relativity community to dismiss all results to the contrary for many years. However, a minority of relativists continued to contend that black holes were physical objects,[71] and by the end of the 1960s, they had persuaded the majority of researchers in the field that there is no obstacle to forming an event horizon.
Einstein was famously wrong about the big bang and gravity waves, the other big consequences of general relativity.

The reader also writes:
That is correct. I said:
It was proved in 1801 that light was not truly a particle, and that has been the dominant view ever since. If it were truly a particle then it would have localized position and momentum, and quantum mechanics teaches that is impossible.

I realize that A. Douglas Stone is an expert on lasers and surely understands this, but he is not correct in the way that he promotes Einstein.

Wednesday, November 13, 2013

Hubble did not convince Einstein






How non-Euclidean geometry entered physics

Danish historian Helge Kragh wrote Geometry and Astronomy: Pre-Einstein Speculations of Non-Euclidean Space in 2012. This appears to be a free copy of what was published in a journal under the title, The first curved-space universe, altho this version seems somewhat different.
This paper examines in detail the attempts in the period from about 1830 to 1910 to establish links between non-Euclidean geometry and the physical and astronomical sciences, including attempts to find observational evidence for curved space. Although there were but few contributors to "non-Euclidean astronomy," there were more than usually supposed. The paper looks in particular on a work of 1872 in which the Leipzig physicist K. F. Zoellner argued that the universe is closed in accordance with Riemann's geometry. ...

Whereas non-Euclidean geometry flourished as a mathematical research field in the last half of the nineteenth century (see the figure on p.8), its connection to the real space inhabited by physical objects was much less cultivated. The large majority of mathematicians did not care whether real space was Euclidean or not; and those who did care only dealt with the subject in a general and often casual way, avoiding to deal seriously with the possibility of determining a space curvature different from zero. After all, that was supposed to be the business of the astronomers.
This paper has a lot of good info, but some things are conspicuously missing.

By far the most important development in this subject is the 1905-8 formulation of special relativity as a 4-dimensional non-Euclidean geometry. That theory gave a geometrical spacetime interpretation to the FitzGerald contraction, Lorentz local time, Maxwell's equations, and various experiments. Poincare had the metric, symmetry group, and covariance, and Minkowski elaborated on those with diagrams and world-lines. This theory was one of the biggest breakthrus in the history of physics, and is in all the textbooks today. There is no evidence that Einstein or anyone else had these ideas independently.

Perhaps Kragh omits this because he is more interested in curved space. But I doubt it because he also says, "The present consensus view, in part based on the inflationary scenario, is that we live in a flat or Euclidean space". Minkowski space is a flat non-Euclidean geometry. He never explains that geometries can be Euclidean or non-Euclidean, and non-Euclidean geometry can be flat or curved. What he says is that he is interested in non-Euclidean geometry entering physics, and Minkowski space did exactly that.

I am not sure who introduced curved space into relativity. That is, I don't know who first had the idea that Minkowski space might be curved. It was probably Marcel Grossmann. He was an expert in non-Euclidean geometry and he proposed such a theory in 1913, with the condition that a gravitational field in empty space has Ricci tensor zero. Einstein published papers denying that such a non-Euclidean geometrical theory was possible, and suggesting less geometrical theories. Grossmann turned out to be exactly correct, until the recent discovery of dark energy. It appears that Levi-Civita and Hilbert eventually convinced Einstein that Grossmann was correct.

According to recent scholarship, Einstein never really accepted the non-Euclidean geometrization of gravity.

Kragh only says this about Grossmann:
In Zurich, Fiedler taught geometry to, among others, Einstein and his friend Marcel Grossmann, who wrote his doctoral thesis under Fiedler. As well known, Einstein’s development of the general theory of relativity relied crucially on Grossmann’s mathematical expertise.
Specifically, what Einstein got from Grossmann was the metric, stress-energy, and Ricci tensors, the gravitational field equations for empty space, and covariant geometrical formulation of the theory.

The story of how non-Euclidean geometry because essential to modern physics is an important one, as it underlies much of 20th century physics from relativity to particle interactions, and everyone gets it wrong. I cannot explain how Kragh overlooks the elephant in the room. Kragh is a well-respected historian and does excellent work. But somehow all of these professors have blinders on when it comes to crediting Einstein, as I have criticized Kragh in 2010 and 2011.

Sunday, November 10, 2013

Einstein was wrong about light






Stone says:
Why is Einstein’s role in quantum theory important and interesting?


Update: Stone says:

Wednesday, November 6, 2013

The story of relativistic synchronization

Max Jammer wrote in a 2004 paper:
In his Gifford Lecture, delivered at the University of St. Andrews in the winter-semester 1955/56, Heisenberg declared: “Within the field of modern physics the theory of relativity has played a very important role. It was in this theory that the necessity for a change in the fundamental principles of physics was recognized for the first time.”(8)

A similar statement had been made by Heisenberg already in 1934 when he declared: “The fundamental presuppositions of classical physics, which led to the scientific picture of the 19th century, had been challenged for the first time by Einstein’s special relativity.”(9) Specifying exactly the premise of classical physics which gave rise to this challenge, Heisenberg continued: “It was the assumption that it is meaningful without further consideration to call two events simultaneous in the case they do not occur at the same place.”

Heisenberg’s statement, that Einstein’s 1905 analysis of the notion of simultaneity and of the concept of time, which — as we shall see later on — Einstein based on the notion of simultaneity, inaugurated the mod-ern physical world picture can be confirmed by the fact that already in 1907 Einstein himself admitted: “It turned out, surprisingly, that it was only necessary to provide a sufficiently precise formulation of the notion of time in order to resolve the difficulty encountered.” (10) Also later, in an impromptu talk, entitled “How I created the theory of relativity,” deliv-ered at Kyoto University on December 14, 1922, Einstein reportedly gave the following account: “Why do the two concepts [i.e., the relativity pos-tulate and the light postulate] contradict each other? I realized that this difficulty was really hard to overcome. I spent almost a year in vain to resolve this problem... Suddenly I understood where the key to this prob-lem lay... An analysis of the concept of time was my solution. Time can-not be absolutely defined, and there is an inseparable relation between time and signal velocity. With this new concept I could resolve all the diffi-culties completely for the first time. Within 5 weeks the special theory of relativity was completed.” (11) ...

Fifty years ago nearly a hundred physicists from all over the world celebrated the 50th anniversary of the theory of relativity in a congress that convened in Bern, where Einstein had written his 1905 relativity paper. At the concluding festive meeting the final lecture was delivered by Max Born who at the end of his talk declared: “Einstein’s leading princi-ple was simply that something of which you could think and form a con-cept, but which from its very nature could not be submitted to an experi-mental test, like the simultaneity of events at distant places, has no phys-ical meaning.” (62) [Jammer, Max, “The Strange Story of the Concept which Inaugurated Modern Theoretical Physics,” Foundations of Physics 34, No. 11 (November 2004), 1617-1641.]
Really? The greatest idea in physics of a century ago was an assumption with no physical meaning, according to Born? There are some who argue that Einstein's genius was to apply pure thought to propose untestable ideas.

You can read about Poincaré–Einstein synchronisation. It was a good idea, but not original to Einstein. There is some dispute about how he learned it. Alberto A. Martínez writes:
Specifically, he complains that I follow Einstein’s account of how clocks synchronized by out-and-back light signals require a convention: the assumption that the speeds of light in opposite directions are equal. Ohanian claims that “Einstein took this procedure from Poincaré’s Science and Hypothesis.” But Ohanian’s claim is mistaken. Ohanian footnotes the English translation (1905) of Poincaré’s book. The problem is that Einstein did not read English at all. As I explained in my book, Einstein read either the original French edition of Poincaré’s book (1902), or its German translation (1904), and neither of these editions says anything about how to synchronize clocks using out-and-back light signals. Ohanian’s confusion arises because he did not use primary sources, he just looked at the English translation which includes an Appendix: Poincaré’s article on “The Principles of Mathematical Physics,” which was absent in the original editions of the book because it was a later address which he presented to the International Congress of Arts and Science in St. Louis, in 1904. Notwithstanding Ohanian’s confusion, we just don’t know where Einstein learned the procedure he described for synchronizing clocks. As I show in my Kinematics, it is conceivable that Einstein learned it from a paper by Poincaré from 1900, which we know Einstein had read by 1906, or perhaps from someone who had read it, or perhaps from Poincaré’s book, which was published in 1905 (Einstein read it in 1905, but we do not know if he read it before writing his first paper on relativity), or perhaps from another source; we just don’t know.
Yes, that is right. Einstein wrote an account in 1949 of how he discovered relativity, and he did not even mention Poincare. When asked about Poincare, he was evasive.

Friday, November 1, 2013

Quantum mechanics can affect the weather

Nate Silver has become the public face of statistics, and his The Signal and the Noise: Why So Many Predictions Fail -- but Some Don't is pretty good, so maybe I should not nitpick. But parts of it are really confused.
Laplace's Demon has been controversial for all its two-hundred year existence. ...

Physicists interpret the uncertainty principle in different ways, but it suggests that Laplace's postulate cannot literally be true. Perfect predictions are impossible if the universe itself is random.

Fortunately, weather does not require quantum mechanics for us to study it. It happens at a molecular (rather than an atomic) level, and molecules are much too large to be discernibly impacted by quantum physics. Moreover, we understand the chemistry and Newtonian physics that govern the weather fairly well, and we have for a long time. [p.113-4]
No, the uncertainty principle has nothing to do with Laplace's Demon. The Schroedinger equation is deterministic, but wave solutions exhibit the uncertainty inequality anyway.

Molecules cannot be too large to be impacted by quantum physics. Most of the molecules only have two atoms, so the idea that quantum mechanics affects atoms but not molecules is silly.

Yes, meteorologists model air as an ideal gas of non-quantum particles, but Silver is leading up to an explanation of how chaos theory put limits on predictability, but those limits are ultimately quantum mechanical.

Thursday, October 31, 2013

Einstein book update


Sunday, October 27, 2013

Confused about Black Hole Paradox

SciAm reports:
Physicists Euphoric but Confused about Black Hole Paradox





Is there any better proof that physics has lost its way?






Friday, October 25, 2013

In defense of compatibilism





Is compatibilism anything more than a semantic gesture?







Which is pretty much how it is.


One of Coyne's reader's comments:
“unless we have perfect knowledge.”


“it completely dispelled the notion of dualistic free will.”




Another says: