Monday, December 31, 2018

What is probability?

Probability is a slippery and widely misunderstood concept. Sometimes it is defined as a frequency, propensity, or degree of belief.

Statistician Andrew Gelman endorses this:
Probability is a mathematical concept. To define it based on any imperfect real-world counterpart (such as betting or long-run frequency) makes about as much sense as defining a line in Euclidean space as the edge of a perfectly straight piece of metal, or as the space occupied by a very thin thread that is pulled taut. Ultimately, a line is a line, and probabilities are mathematical objects that follow Kolmogorov’s laws. Real-world models are important for the application of probability, and it makes a lot of sense to me that such an important concept has many different real-world analogies, none of which are perfect.
Mathematically, I agree with him. Those axioms do not even have anything to do with what non-mathematicians think of as randomness.

The curious thing is that he believes that quantum mechanics violates the laws of probability. This is because he was a physics major before becoming a statistician, and his professor gave him a faulty explanation of the double slit experiment.

The faulty explanation sometimes goes under the name "quantum logic". It says that the double slit experiment proves that the law of the excluded middle is false. You expect that if you fire a particle at a double slit, it goes thru one slit or the other. But you see an interference pattern, and not just the logical sum of particles going thru one slit or the other.

The much more reasonable explanation is the the particle is not a classical particle, but a wave. Waves show interference patterns, and nothing is surprising.

So which would you rather believe, that light has wave properties, or that the mathematical laws of logic and probability are broken?

Obviously, light has wave properties. The alternative is lunacy. It is like having a theory that predicts 2+2 and measuring 4, and then concluding that 2+2 is not 4. No, the better conclusion is that something is wrong with your theory or your measurement.

The theorems about conditional probability and the law of the excluded middle are mathematically valid, and as true for quantum mechanics as anything else.

Gelman says that the probability of the particle hitting a patch on the target screen should be the average of the conditional probabilities, where the condition is passing thru one slit or the other. But such a formula would not give an interference pattern.

His error is thinking that a particle goes thru one slit or the other. Quantum mechanics says that it does not.

When he previously posted about this, others tried to explain the physics to him. But he was not interested in the physics of quantum mechanics. He is interested in applying statistics to social sciences. If conventional probability theory is not good enough for physics, then he wonders whether there should be a generalized probability theory to cover both physics and social sciences.

The physics problem is that unrealized experiments have no results. Maybe there is an analogous principle in the social sciences, I don't know.

For how different people view probably, see this:
Michael Lewis's book "The Undoing Project" is concerned with the (mathematical) psychologists Daniel Kahneman and Amos Tversky. (Kahneman won the 2002 Nobel Prize; Tversky died in 1996.) On page 157, this question is quoted:

The mean IQ of the population of eighth graders in a city is known to be 100. You have selected a random sample of 50 children for a study of educational achievement. The first child tested has an IQ of 150. What do you expect the mean IQ to be for the whole sample.

Tversky and Kahneman stated: "The correct answer is 101. A surprisingly large number of people believe that the expected IQ for the sample is still 100" in Psychological Bulletin, vol. 76, 105--110 (1971).
So he got a Nobel Prize (actually a Bank of Sweden prize in economics) for saying people are irrational for reasoning differently from him.

I do not think I would give 101 as the answer. It is much more likely that the test was mis-normed, or that the children were unusual, or that the sampling was not random. NN Taleb mocks this thought experiment with a more extreme example:
Fat Tony is the foil to Dr. John. Dr. John is nerdy, meticulous, careful and academic; Fat Tony is confident, loud, careless and shrewd. Both of them make errors, but of different types. Dr. John can make gigantic errors that affect other people by ignoring reality in favor of assumptions. Fat Tony makes smaller errors that affect only himself, but more seriously (they kill him). ...

The most famous contrast between the two is the question of what to think about a fair coin that has tossed heads 99 times in a row. Dr. John insists that because the coin is fair, the answer has to be 50%.
Fat Tony deduces that the coin is not really fair, and says that heads is much more likely.

This dichotomy in thinking goes back to Plato and Aristotle. Plato would make purely abstract theories, and doggedly insist on them. Aristotle was the empiricist. If theory differed from practice, Plato would side with the theory, and Aristotle with the practice.

Update: Gelman has commenters who make the usual mistakes about Bell and interpretations of quantum mechanics. Some say that Bell proved that locality implies an inequality inconsistent with QM, so the experiments prove nonlocality. Actually Bell assumed local hidden variables, so the experiments certainly do not prove nonlocality. They only show that local hidden variable models don't work.

Thursday, December 27, 2018

How Kaluza-Klein ruined Physics

There is a new European paper on Albert Einstein and the fifth dimension. A new interpretation of the papers published in 1927. The fifth dimension is Kaluza–Klein theory.

This is one of those subjects where theoretical physicists have crazy ideas about how things ought to be.
In 1919, the German mathematician Theodor Kaluza developed a theory that maintained all the formalism of Riemannian geometry but extended the geometry's reach by proposing the possibility that Nature in fact utilized a five-dimensional spacetime, with electromagnetism appearing as a natural consequence of the unseen fifth dimension (the same idea was actually proposed by the Finnish physicist Gunnar Nordström in 1914, but was ignored). Kaluza communicated his idea to Einstein in the form of a draft paper, who was initially very enthusiastic about the concept of electromagnetism springing from the fifth dimension. But despite promises to assist Kaluza in publishing, Einstein sat on the idea for another two years before he finally recommended Kaluza's work for publication. ...

Consequently, in 1926 the Swedish mathematician Oskar Klein reexamined Kaluza's theory and made several important improvements ... Since that time, theories involving extra hidden (or compactified) dimensions have become known as Kaluza-Klein theories.
Big shot physicists continue to write papers about the idea today.

What makes these theories attractive is that gravity can be formulated as a geometric theory of curvature of 4-dimensional spacetime, and electromagnetism as a geometric theory of curvature of a circle bundle over spacetime. The circle bundle can be viewed as a 5th dimension to spacetime, or as a tiny circle at each spacetime point. See here for an explanation.

Einstein was strangely antagonistic to this geometric view. So are some modern physicists, like Steve Weinberg. The physics textbooks rarely mention it.

The Kaluza-Klein theories would be great if they emphasized this geometric view. But they don't. Instead, the starting point for those theories is that the geometric view is defective because there is no coupling between electromagnetism and gravity.

According to unified field theory dogma, as accepted by Einstein and most modern theoretical physicists, all forces should be unified in the way that Maxwell unified electricity and magnetism and light waves. It is impossible to understand magnetism without electricity, because they are both just manifestations of the same thing.

But with electromagnetism and gravity, you can learn them separately. When solving a problem, you can compute the electromagnetic effect, and then the gravity effect, and add them. There is a unified geometrical description of both theories, but there is no coupling, and you cannot pretend that they are the same.

It is like belief in God. You can believe in one god, or in multiple gods. If you believe in multiple gods, you don't see the work of one god necessarily has anything to do with the work of another. But try telling that to a believer in one god, and he will stubbornly insist that one god is responsible for everything, no matter what you say.

As it is with unified field theory. You just cannot convince a modern theoretical physicist that the fundamental forces are uncoupled. They will make the most extravagant assumptions, such as 6 extra Calabi-Yau dimensions, to justify their unified field theory preferences.

I used to think that unified field theory meant putting all the forces under a common geometric mathematical formalism. But the Standard Model does that, and the unified field theorists reject it.

The above paper quotes Einstein in 1921:
A theory in which the gravitational field and the electromagnetic field do not enter as logically distinct structures would be much preferable. H. Weyl, and recently Th. Kaluza, have put forward ingenious ideas along this direction; but concerning them, I am convinced that they do not bring us nearer to the true solution of the fundamental problem. I shall not go into this further [...]
The paper does not even mention the fact that you do get a very nice geometric theory if you are willing to accept the fields as "logically distinct structures".

That nice geometric theory turned out to be essential for the Standard Model. I cannot figure out who deserves credit for it. My best guess is Weyl, but it could have been Nordström or someone else. I also cannot figure out how Einstein convinced everyone that the forces have to be coupled in order to be "the true solution of the fundamental problem."

I think that historians should recognize Kaluza-Klein theory as a point where Physics went down a wrong path. They took a very good idea, the geometrization of the fundamental forces, with a very bad idea, a belief that all forces are coupled, and got a dead-end theory in 1921.

It appears that for a whole century, no one had the good sense to separate out the good idea from the bad idea.

Monday, December 24, 2018

The math of the standard model

Adam Koberinski has a new article on the creation of the Standard Model of high-energy physics:
I detail three major mathematical developments that led to the emergence of Yang-Mills theories as the foundation for the standard model of particle physics. In less than ten years, work on renormalizability, the renormalization group, and lattice quantum field theory highlighted the utility of Yang-Mills type models of quantum field theory by connecting poorly understood candidate dynamical models to emerging experimental results.
The model was the result of developments in mathematical physics from 1960-1975. The paper describes these pretty well.

As the paper explains, renormalizing gauge theories was the crucial development.

The story ends in about 1975, with a satisfactory theory of all four fundamental forces, and agreement with experiment for the foreseeable future. So did physicists celebrate solving all their big problems? No. They embarked on string theory and billion-dollar searches for SUSY particles. None of this has amounted to anything.

Historians will record a golden age of theoretical physics that ran from Maxwell in about 1860 to the standard model in 1975.

Friday, December 21, 2018

Dawid tries to defend string theory

Not many string theorists are willing to address shortcomings to the general public. Philosopher Richard Dawid tries:
String theory has not even come close to a complete formulation after half a century of intense research. On the other hand, a number of features of the theory suggest that the theory, once completed, may be a final theory. It is argued in this chapter that those two conspicuous characteristics of string physics are related to each other. What links them together is the fact that string theory has no dimensionless free parameters at a fundamental level. The paper analyses possible
implications of this situation for the long term prospects of theory building in fundamental physics.
Dawid is an advocate of string theory, and well-connected to string theorists, so you can assume that he is putting the theory in its most favorable light.

And yet he alternates between saying string theory is a possible "final theory" to explain all physical phenomena for now and into the indefinite future, and saying that it is a total bust with no relation to the real world at all.

He even goes so far as to say that there is a relation between saying a theory explains everything and saying it explains nothing. The link is that both such theories might be expected to lack free parameters. String theory lacks any such parameters that might allow testing or prediction.

He seems to realize how absurd this all sounds, because no theory like this has ever had any merit before. But he says that it is unfair to judge string theory based on standards of the past. He says "there is little reason to expect that theory building at the present stage can be judged according to criteria that seemed adequate in the past."
A natural question regarding the chronic incompleteness of string theory is: why is it so difficult to develop string theory into a fully fledged theory? ... Should we therefore understand chronic incompleteness as a core characteristic of a final physical theory? ... String theory is chronically incomplete (and lacks a promising perspective for quantitative empirical testing in the foreseeable future).
I am puzzled by his frequent usage of "chronic incompleteness" without defining it. I see two possible definitions:

chronic incompleteness - physicists keep trying to develop it into a meaningful theory, and keep failing.

chronic incompleteness - it fails to make any predictions, even with complete initial data.

The first is like "chronic pain", and the second is just a fancy way of using time as an adjective.

I don't know which he means, but string theory fails on all counts anyway.

These failures of string theory were clearly identified about 25 years ago, but the research program as continued, as if nothing were wrong.

After writing this, I see Peter Woit comments.

Wednesday, December 19, 2018

Whether the nuclear age is sustainable

An Italian physicist writes:
The unsustainable legacy of the Nuclear Age

In the dispute on the beginning of the Anthropocene it has been proposed, among many, a precise date, July 16th 1945, when the Trinity Test exploded the first atomic bomb in the desert of Alamogordo2, which inaugurated the Nuclear Age. On the other hand, the almost contemporaneous Ecomodernist Manifesto proposed that, among other things, "nuclear fission today represents the only present-day zero-carbon technology with the demonstrated ability to meet most, if not all, of the energy demands of a modern economy."3

I do not agree with either of these thesis. The Atomic Age has undoubtedly been a tremendous acceleration of the impact of human activities on natural environment, but in my opinion it joined, however it exacerbated, the trend embarked upon since the First Industrial Revolution, when Capitalism adopted radically new (scientific) methods to exploit and "commodise" Nature and its resources. This breakthrough kicked off the development of industrial processes carried out in physical and chemical conditions further and further away from the conditions of the natural environment on Earth surface, so that they introduced products and procedures which are incompatible with such environment, and therefore produce a permanent and irreversible contamination.4 ...

It is seldom acknowledged the tremendous burden that the Nuclear Age leaves on future generations, and the environment, for an extremely long time. Nuclear processes, and products, are activated at energies millions of times higher than the energies of chemical processes, and consequently they cannot be eliminated by the natural environment on Earth.
He goes on to detail costs of nuclear power.

My problem with this is that there is no comparison to the costs of the alternatives. An article on the costs of coal power would be much worse.

While he has many gripes about nuclear power, he doesn't refute the thesis that nuclear fission is the only practical zero-carbon technology.

Tuesday, December 18, 2018

Theory that Einstein paper was ghostwritten

Tomasz Bodziony writes The birth of a genius. 1905:
Is Einstein's article not original, but rather a secondary one to Poincaré's work? Was Henri Poincaré the factual creator of the Special Theory of Relativity? Is the situation even worse for Einstein? There are three explanations for the strange coincidences of June 1905. The first one is the traditional version: Einstein himself wrote his work without reading the works of Lorentz and Poincaré. The date-specific similarity between the publication of Einstein's work and the publication of Poincaré's works was a coincidence. The Göttingen conference had no connection with the discussed events. The second possibility is that Einstein got acquainted with the works of Poincaré and Lorentz and his work was written in a hurry as it had been ordered by the participants of the seminar in Göttingen: David Hilbert and/or Hermann Minkowski, and was quickly accepted for publication in order to precede the publication of H. Poincaré's works. If that was the case, then the work "Zur Elektrodynamik bewegter Körper" from 1905 would be plagiarized. Finally, the third possibility is the most radical one.
He goes on to argue that Einstein’s famous 1905 relativity paper was really ghost-written by Hilbert and Minkowski, in order to steal credit from Poincare. Einstein would not have been capable of writing such a paper himself.

His theory is too radical for me, but the author does explain why the explanations given by Einstein and historians have holes.

Einstein did not reference Lorentz and Poincare, but Einstein often published the work of others without attribution. Everyone agrees to that. The only question is how much Einstein knew of other work. The Einstein historians say that Einstein knew about the older works, and that his 1905 paper independently rediscovered relativity. If Einstein knew about Lorentz's 1904 paper and Poincare's short 1905 paper, both of which were available to Einstein before he wrote his relativity paper, then Einstein had nothing original.

Poincare, Hilbert, and Minkowski were mathematicians. When they wrote about relativity, they are more precise, and they turn it into a more coherent theory. Einstein's 1905 paper is mathematically sloppy. I do not think that it could have been ghost-written by one of those mathematicians, unless he was being deliberately sloppy.

Sunday, December 16, 2018

How to stop Copenhagen collapses

A philosophy of science article says:
In the science fiction novel Quarantine, Greg Egan imagines a universe where interactions with human observers collapse quantum wavefunctions. Aliens, unable to collapse wavefunctions, tire of being slaughtered by these collapses. In response they erect an impenetrable shield around the solar system, protecting the rest of the universe from human interference and locking humanity into a starless Bubble.
This is funny. This would be the logical conclusion of some explanations of the Copenhagen interpretation.

With no humans to make observations, space aliens might happily live in Schroedinger cat states, where they are half-alive and half-dead.

This sort of thought experiment drives a lot of cosmologists to reject Copenhagen, and believe in many-worlds or some other nonsense.

Another web paper says:
In popular articles about quantum computing it’s common to describe qubits as having the ability to “be in both |0>|0> and |1>|1> states at once”, and to say things like “quantum computers get their power because they can simultaneously be in exponentially many quantum states!”

I must confess, I don’t understand what such articles are talking about.
Those explanations are common because of that stupid Schroedinger cat story, so bits can be on and off at the same time.

Scott Aaronson is a believer in quantum computing, but he often explains that it is a false myth that quantum computers get their power from qubits being in two states at the same time.

So where do quantum computers get their alleged power? That is never convincingly explained. Aaronson has tried many times, and I think that he is writing another book on the subject. Sometimes he says it is from negative probabilities or some other obscure quantum technicality. He has never been able to get his point across to science journalists, so he has quit talking to them.

Friday, December 14, 2018

Deriving the constancy of light speed

Lots of theoretical physicists, such as string theorists, try to derive physical laws from first principles, instead of relying on observation or experiment.

When has this ever worked?

Some people think that Einstein created special relativity this way. That is completely false, and special relativity was developed directly from experiment.

Nevertheless, it seems possible that special relativity could have been derived from first principles. Here is a recent paper that gives such a derivation:
An exposition of special relativity without appeal to "constancy of speed of light" hypotheses

We present the theory of special relativity here through the lens of differential geometry. In particular, we explicitly avoid any reference to hypotheses of the form "The laws of physics take the same form in all inertial reference frames" and "The speed of light is constant in all inertial reference frames", or to any other electrodynamic phenomenon. For the author, the clearest understanding of relativity comes about when developing the theory out of just the primitive concept of time (which is also a concept inherent in any standard exposition) and the basic tenets of differential geometry.
I have made similar arguments on this blog, as well as taking it further to electromagnetism and the standard model of particles.

Thursday, December 13, 2018

SciAm joins the attack on Black patriarchy

Fifty years ago, Scientific American was the best general-interest science magazine in the world. It is still good, but has gone downhill, both in promoting schlock science and adhering to leftist politics. Eg, see this ridiculous article saying that the USA needs DACA privileges for illegal aliens in order to do science research.

I mentioned MeToo allegations against a prominent science popularizer, and now SciAm piles on:
But my own experience—backed by data—teaches me that Black patriarchy is real and the harm specifically to Black women is significant. In this case, the harm is multidimensional ...

It’s true that some details of these allegations have yet to be corroborated, ... But in my view, I believe the claims are credible, which means he directly harmed multiple women, most egregiously by allegedly raping a member of his own already marginalized community.
She says this in spite of the fact that she knows the guy personally, and has never seen him do anything inappropriate. She and SciAm explain the uppercase Black:
I have chosen to capitalize the word “Black” and lowercase “white” throughout this book. I believe “Black” constitutes a group, an ethnicity equivalent to African-American, Negro, or, in terms of a sense of ethnic cohesion, Irish, Polish, or Chinese. I don’t believe that whiteness merits the same treatment. Most American whites think of themselves as Italian-American or Jewish or otherwise relating to other past connections that Blacks cannot make because of the familial and national disruptions of slavery. So to me, because Black speaks to an unknown familial/national past it deserves capitalization.
No, this is so stupid and illogical that it is embarrassing to see it on I had no idea that some editors believe that Whites are not worthy of an uppercase W. I think that I will start capitalizing the word.

Saying "multiple women" makes it sound as if there are similar or corroborrating allegations, but there are not. One involved a women who was showing off a shoulder tattoo while taking a selfie with him at a party, and he looked to see if the tattoo included Pluto. He would have been rude not to look for Pluto, considering he wrote a book on whether Pluto is a planet.

Saying "claims are credible", just means that someone told a story about events 30 years ago that could have happened. There is no evidence other than someone telling a story 30 years after the fact. From that she leaps to saying that this means that he raped a black girl as part of the "Black patriarchy".

This looks like libel to me, but there is no practical legal remedy. I would rather not even mention his name.

Here is more politicized science, from Scott Aaronson:
Michael Says: I’m surprised you didn’t mention the big one- where can we find evidence that Donald Trump conspired with the Russians?

Scott Says: Michael #26: Again, not worth wasting a question on. Facts in the public record made it obvious since even before the election that they did collude, modulo uninteresting hairsplitting about the meaning of “collude.” Like, Trump openly urged the Russians to hack the emails. In the norms that used to apply, in the world that made minimal sense, that would already count as collusion and prevent him from being president (along with ~500 other violations of basic democratic norms). I’d rather ask the NP-genie: what can we do or say to get back to that world?
No, Trump did not openly urge the Russians to hack the emails. Even if he did, anything done in the open is not a conspiracy. And there is no law against a presidential candidate colluding with the Russians to seek support.

SciAm columnists and Aaronson are entitled to their political opinions, of course, but we have a scientific and academic establishment that is overwhelmingly leftist, and extraordiarily gullible in believing claims that support their leftist politics. I do not trust them when they give opinions on global warming or quantum computing.

Wednesday, December 12, 2018

How the apple inspired Newton

A physics blogger writes:
As someone whose job it is to help people understand and appreciate physics, I absolutely hate the way most people talk about Isaac Newton and how he developed his theory of gravity. It's not the apple bit that I have a problem with; that's an important part of the story, and even historically accurate!

I always assumed that Isaac Newton's big insight upon seeing the apple fall was that the Moon was falling from the same gravity.

This article says that there is evidence that Newton really was inspired by an apple, but his big insight was that the Earth was pulling on the apple in the same way that the apple was pulling on the Earth. The Earth also falls toward the apple, ever so slightly.
We can thank this little touch of plague for virtually all of Newton's scientific legacy: in that single impromptu gap year, he had his epiphany about gravity, discovered that white light is made up of all the colors in the spectrum, and basically invented calculus.
The problem with that story is that Newton got involved in nasty priority fights over ideas that he failed to publish until many years later. So he could be exaggerating how much he figured out in that year.

Monday, December 10, 2018

Deutsch says single universe is stone dead

Quanta mag has an article about a recent paper on how the Wigner's friend paradox should unfluence interpretations of quantum mechanics:
Now, a new thought experiment is confronting these assumptions head-on and shaking the foundations of quantum physics.
This is interesting, but it does not affect any predictions of quantum mechanics. It only involves what one observer thinks that another observer is seeing.
Deutsch thinks the thought experiment will continue to support many-worlds. “My take is likely to be that it kills wave-function-collapse or single-universe versions of quantum theory, but they were already stone dead,” he said. “I’m not sure what purpose it serves to attack them again with bigger weapons.”
He is a die-hard supporter of the many-worlds interpretation. He apparently thinks that other interpretations have been shown to be "stone dead".

It is a little crazy to think that some stupid thought experiment is convincing about the existence of non-observable parallel universes.

Friday, December 7, 2018

China Has the Lead in Quantum Encryption

The NY Times reports:
The Race Is On to Protect Data From the Next Leap in Computers. And China Has the Lead.

The world’s leading technology companies, from Google to Alibaba in China, are racing to build the first quantum computer, a machine that would be far more powerful than today’s computers.

This device could break the encryption that protects digital information, putting at risk everything from the billions of dollars spent on e-commerce to national secrets stored in government databases.

An answer? Encryption that relies on the same concepts from the world of physics. Just as some scientists are working on quantum computers, others are working on quantum security techniques that could thwart the code-breaking abilities of these machines of the future.

It is a race with national security implications, and while building quantum computers is still anyone’s game, China has a clear lead in quantum encryption. As it has with other cutting-edge technologies, like artificial intelligence, the Chinese government has made different kinds of quantum research a priority.

“China has a very deliberate strategy to own this technology,” said Duncan Earl, a former researcher at Oak Ridge National Laboratory who is president and chief technology officer of Qubitekk, a company that is exploring quantum encryption. “If we think we can wait five or 10 years before jumping on this technology, it is going to be too late.”
This is ridiculous. I am a quantum computer skeptic, but put that aside. Quantum encryption can be done on a small scale, but it is commercially useless for many reasons. Messages cannot be authenticated. It is slow and cumbersome. It is subject to hardware attacks. It has never worked as well as the models assume. It does not solve any problem that is not already solved in a much better way.
With communications sent by traditional means, eavesdroppers can intercept the data stream at every point along a fiber-optic line. A government could tap that line just about anywhere. Quantum encryption cut the number of vulnerable spots in the Beijing-Shanghai line to just a few dozen across 1,200 miles, Professor Lu said.
No, most data today is sent encrypted. Governments cannot just tap the lines at intermediate points, because they would just get encrypted data.
At places like the University of Chicago, researchers hope to go a step further, exploring what are called quantum repeaters — devices that could extend the range of quantum encryption.
Yes, that is one of the big problems with quantum encryption. Ordinary encryption, as used today, can use cheap routers with no danger of security loss. Quantum encryption needs trusted quantum repeaters everywhere, and no one has invented one yet.

Wednesday, December 5, 2018

AAAS polls MeToo as a breakthrough

AAAS Science mag announces:
It’s that time of the year again: Science’s reporters and editors are homing in on the Breakthrough of the Year, our choice of the most significant scientific discovery, development, or trend in 2018. That selection, along with nine runners-up, will be announced when the last issue of the year goes online on 20 December. ...

The #MeToo movement made significant gains in science. Several institutions upheld long-standing allegations against prominent scientists accused of sexual harassment, discrimination, or bullying, and a U.S. National Academies of Sciences, Engineering, and Medicine report called for systemic changes to prevent such abuse. ...

Editor’s note: We originally included the claim of gene-edited babies as a candidate; we have since removed it to avoid giving the mistaken impression that Science endorses this ethically fraught work.
So AAAS views #MeToo as a scientific breakthrough, and endorses that ethically fraught work?!

The winner is being determined by an online vote, so we will see if the feminists have taken over.

Recent victims of #MeToo include Larry Krauss and Neil DeGrasse Tyson. I am not going to repeat the gossip here. In one accusation, a fan showed him a solar system tattoo on her arm, and he asked to see if it included Pluto. I thought that women get tattoos to show them. The accusations are extremely petty, and do not belong in a science journal.

Complaining about MeToo accusers is like complaining about termites. Termites do what termites do. It is unfortunate to see the leading science popularizers get maligned like this. Who is going to take on the responsibility to explaining science to the public? Maybe eunuchs or lesbians or Moslems will have to be recruited.

Maybe 2018 will go down in the history of science as the beginning of the end of modern physics. The period started with Maxwell and others in the late 19th century. Now physics news is dominated by ridiculously overhyped bogus stories about the multiverse and other nonsense, failed attempts to find susy particles and quantum computers, censoring physicist Alessandro Strumia for telling the truth about women in physics, and the MeToo movement sabotaging careers.

Monday, December 3, 2018

The Einstein God Letter is for sale

An auction is selling an Einstein letter that says:
The word God is for me nothing but the expression of and product of human weaknesses, the Bible a collection of venerable but still rather primitive legends,” the message reads. “No interpretation, no matter how subtle, can (for me) change anything about this. ...

For me the unadulterated Jewish religion is, like all other religions, an incarnation of primitive superstition. And the Jewish people to whom I gladly belong, and in whose mentality I feel profoundly anchored, still for me does not have any different kind of dignity from all other peoples. As far as my experience goes, they are in fact no better than other human groups, even if they are protected from the worst excesses by a lack of power. Otherwise I cannot perceive anything ‘chosen’ about them.
In spite of these opinions, being a Jew was very important to Einstein, and he was involved in Zionist causes all his life.

Judaism is funny that way. Many Jews identify with Judaism and Jewish culture very strongly, even tho they do not seem to believe in any of the religious aspects.
“Einstein often uses the word God — ‘God does not play dice with the universe,’” Rebecca Newberger Goldstein, who teaches philosophy and wrote “Plato at the Googleplex: Why Philosophy Won’t Go Away,” said in an interview. “A lot of physicists do this. It misleads people into thinking they’re theists, they believe in God. It’s a metaphorical way of talking about absolute truth. Einstein used it metaphorically and playfully.”

She said he had been religious when he was a child but “lost his religion and science took over.”
This is confusing to non-physicists. Saying that "science took over" is not right either, as Einstein had his share of unscientific beliefs.

Friday, November 30, 2018

Economist cites Schroedinger's immigrant

Here is a foolish non-physics reference to quantum mechanics.

Economist David Henderson writes in favor of open borders:
In a post this morning, Cafe Hayek’s Don Boudreaux points out the contradiction in opposing immigrants because they work and opposing them because they go on welfare, that is, don’t work.

Jon Murphy, a Ph.D. student at George Mason University, where Don teaches, and a frequent commenter on this site (as well as an Econlib Feature Article author) sums it up beautifully:

Schrodinger’s Immigrant: simultaneously stealing jobs and too lazy to work.

Of course, Jon’s reference is to Schrodinger’s cat.
If Schroedinger's immigrant is like the cat, then you have to look at the immigrant too see if he is stealing jobs or too lazy to work.

Or as a comment explains:
It is completely possible for immigrants to be a problem for both working and not working. An example — If 10 million immigrants suddenly find a home in the US, the economy cannot instantly absorb them. Therefore some will find work and others will not, thereby making the double whammy that some are competing for jobs with citizens, and others are sucking dollars out of the welfare system.
Henderson ignores this, and just lets others take the libertarian view that the immigrants should be able to do whatever they want.

Wednesday, November 28, 2018

Letting quasars substitute for free will

SciAm has an article on Photons, Quasars and the Possibility of Free Will:
The nature of free will has long inspired philosophical debates, but it also raises a central question about the fundamental nature of the universe. Is the cosmos governed by strict physical laws that determine its fate from the big bang until the end of time? Or do the laws of nature sometimes allow for things to happen at random? A century-old series of physics experiments still hasn’t been able to settle the question, but a new experiment has tilted the odds toward the latter by performing a quantum experiment across billions of light-years. ...

Rather than using a random number generator in the lab to decide which photon measurement to make, the experimenters used quasars.

Quasars are brilliant beacons of light powered by supermassive black holes in the centers of distant galaxies. The team used random fluctuations in the light from quasars to determine how the photons were measured. Since the light from a quasar has to travel for billions of years to reach us, the fluctuations in brightness happened billions of years before the experiment was done—billions of years before humans even walked the Earth. So, there is absolutely no way for it to be entangled with the experiment.

The result was just what quantum theory predicts. Thus, it looks like there really are no deterministic hidden variables, and randomness is still possible throughout the cosmos.
This is just another Bell test experiment, confirming what has been the conventional wisdom for 90 years. There are no local hidden variables. It doesn't really have much to do with free will.

A lot of experiments use randomized inputs, and that is easy to do if the experimenter has some free will to make choices. If he doesn't, then one can question where the randomness is going to come from. You could toss coins, but then you worry that the coin tosses have some subtle correlation with the particle spins in the experiment, and that the correlation is somehow tricking us into believing in quantum mechanics.

So you can get your randomness from a distant quasar. Does that make you feel better as a result?

All this shows is that the known laws of physics are not 100% deterministic. It doesn't really show that we have free will. It does disprove arguments against free will that are based on saying that the laws of physics are deterministic. The known laws are not deterministic.

Sunday, November 25, 2018

Motl complains about the end of Physics

Lubos Motl writes:
Fundamental physics refused to obey the wishes of Horgan's. In the 22 years since 1996 when Horgan declared the end of science in his book, we have seen the discovery of Matrix Theory, AdS/CFT and all of its known implications, discovery of the cosmological constant, gravitational waves, Higgs boson, plus some possible experimental anomalies suggesting physics beyond the Standard Model. Sen's tachyon minirevolution, twistor and amplituhedron uprising, landscape and its KKLT realization, Swampland, ER-EPR correspondence, and dozens of comparably similar developments in string theory.
None of these things told us anything new about fundamental physics. From about 1850 to 1980, we had fundamental physics breakthrus every 5 years or so. Since then, nothing.
Already during his lifetime, Einstein was celebrated for some well-established insights such as [relativity etc...] And despite his flawed non-quantum approach, his efforts to find the unified field theory became a template for the modern search for a theory of everything.
Yes, that sums up a lot of what is wrong with theoretical physicists. They follow Einstein's flawed approach.
I think it's a right decision to surrender in this media war against the anti-physics morons. They have won and taken over almost all the media. The number of imbeciles and liars is just way too high and I have been tilting at windmills for way too long. A vast majority of newspaper articles about theoretical physics – and tons of other topics – spread "stories" and "narratives" that have virtually no basis in the truth whatsoever. Serious physicists have been too passive for too long and they have allowed the situation to deteriorate this much.
Yes, the media promotes all sorts of kooky ideas about physics.

Friday, November 23, 2018

Schroedinger grandson plugs quantum computers

Scott Aaronson posts:
And that’s why, today, I’m delighted to have a special guest post by my good friend Terry Rudolph.  Terry, who happens to be Erwin Schrödinger’s grandson, has done lots of fascinating work over the years in quantum computing and the foundations of quantum mechanics, and previously came up on this blog in the context of the PBR (Pusey-Barrett-Rudolph) Theorem.  Today, he’s a cofounder and chief architect at PsiQuantum, a startup in Palo Alto that’s trying to build silicon-photonic quantum computers. ...

Can we/should we teach Quantum Theory in Junior High?
by Terry Rudolph

Should we?

Reasons which suggest the answer is “yes” include:

Economic: We are apparently into a labor market shortage in quantum engineers
The link is to a NY Times article a month ago:
The Next Tech Talent Shortage: Quantum Computing Researchers

Christopher Savoie, founder and chief executive of a start-up called Zapata, offered jobs this year to three scientists who specialize in an increasingly important technology called quantum computing. They accepted.

Several months later, the Cambridge, Mass., company was still waiting for the State Department to approve visas for the specialists. All three are foreigners, born in Europe and Asia.

Whether the delays were the result of tougher immigration policy or just red tape, Mr. Savoie’s predicament was typical of a growing concern among American businesses and universities: Unless policies and priorities change, they will have trouble attracting the talent needed to build quantum technology, which could make today’s computers look like toys. ...

If a quantum computer can be built, it will be exponentially more powerful than even today’s supercomputers.
No, it will not be exponentially more powerful, as Scott Aaronson is fond of pointing out.

And there is considerable doubt about whether quantum computers can be built at all.

The whole field is a gigantic scam.

There are no overseas scientists in quantum computing that have anything to offer the USA. There is no good reason to grant them visas.

Rudolph's new book, and his proposed Junior High course, consist mostly in lessons in programming hypothetical qubits that no one has successfully constructed. This makes about as much sense as teaching kids to play the Harry Potter sport of Quidditch, which exists only the imagination of J.K. Rowling and her readers.

Thursday, November 22, 2018

Glashow defends textbook quantum mechanics

I sometimes complain that crackpot ideas have taken over the popularizations of physics, in part because the professors who know better have been silent. But I am happy to say that a distinguished physicist has spoken up to criticize a popular quantum mechanics book.

Sheldon Lee Glashow reviews a book to criticize these ideas:
Schroedinger's cat is simultaneously alive and dead.
We should accept non-falsifiable theories, because no theory is really falsifiable anyway.
Theories cannot be verified either.
Copenhagen interpretation has clouded the minds of physicists.
Glashow is right about these points. Attacking Copenhagen because of Schroedinger's cat is foolishness. The cat is only half-dead in the sense that our knowledge is imperfect, and not because of some fundamental shortcoming of quantum mechanics.

The Becker book attacks Copenhagen because it says that the underlying philosophy of logical positivism is faulty. I do believe it is correct to say that quantum mechanics was founded on a logical positivist philosophy. I think that is a good thing, not a bad thing.

Unfortunately, logical positivism has fallen out of favor among philosophers, and so has the Copenhagen interpretation. Was one shift a consequence of the other? I don't know.

The situation is muddied by the fact that no one defends logical positivism anymore. Copenhagen and positivism seem to have a lot of believers among physicists, but not so many expressing public opinions. Many physicists defend variants of Copenhagen, but prefer to call it consistent histories or QBism.

Wednesday, November 21, 2018

Einstein's unified field theory dream is dead

Dennis Overbye writes in the NY Times:
Is Albert Einstein finally dead?

Yes. The old sage took his last breath and muttered his last indecipherable words, in German, on April 18, 1955. But lately he has been dying a second death, if one believes a new spate of articles and papers bemoaning the state of contemporary physics.

Never mind the recent, staggering discovery of gravitational waves: ripples in space-time that Einstein predicted a century ago, and which indicate the universe is peppered with black holes that shred and swallow stars.

No, something much deeper than gravity or quantum theory, Einstein’s other misbegotten legacy, is at stake.

More than anyone, it was Einstein who set the goal for modern science: the search for a final theory of everything, a “unified theory,” he said, that would explain why there was no other way to put together the universe than the one we seem to live in.

Or, as he famously put it, “What interests me is whether God had any choice in the creation of the world.”

Roll over, Albert.
He goes on to explain how string theory, supersymmetry, landscape, multiverse, unified field theory, etc. are all dead. Work in these directions has failed, even if many don't want to admit it. Peter Woit and Sabine Hossenfelder have comments.

Einstein's goal of a unified theory was foolish anyway.
But the amount of this dark energy is smaller than the predicted value of the cosmological constant by a factor of 1060. ...

According to them, atoms — the stuff of you, me and the stars — account for only 5 percent of the cosmos by weight. Dark matter, of which we know nothing except that its collective gravity sculpts and holds the galaxies together, amounts to 25 percent.

The remaining 70 percent is dark energy, pushing everything apart; we don’t know anything about that, either. We only know that this “dark sector” exists because of the effect of its gravity on the luminous universe, the motions of stars and galaxies.

A theory that leaves 95 percent of the universe unidentified is hardly a sign that science is over.
Wait -- there is a prediction for the density of dark energy, but we don't know anything about it? So how was the prediction made?

We actually know a lot about dark matter and dark energy, and it is possible that we now know essentially all that we will ever know.

Dark matter has gravity, but does not interact with electricity or light. Its gravitational effects are well understood. What else is there to understand?

Dark energy could be the zero point energy of the vacuum. All quantum systems have such a zero point energy. We can't derive it from first principles, or from the geometry of a Calabi-Yau space, but quantum theory suggests that we should expect it. It appears to be homogeneous, isotropic, and Lorentz invariant. It is just the energy of the vacuum. There may be no more to explain.
Maybe we don’t understand gravity after all, some astronomers say. “I worry that we deify Einstein too much,” Stacy McGaugh, an astronomer at Case Western Reserve University, told Gizmodo in June.
We definitely deify Einstein too much.
If scientists want any gift for the holidays, it’s some new physics that would break the stalemate of these “standard models” and provide new clues to our existence.
This is like a medical researcher hoping to discover some new disease, or the CIA hoping to discover some new terrorist network, or a computer scientist hoping to find flaws that destroy our information infrastructure.

If the disease is already out there killing people, then sure you want to figure out how to diagnose and treat it. But why would you hope for the disease?

Physicists have figured out the four fundamental forces. The big problems have been solved. That is a good thing, not a bad thing. Am I supposed to hope that the laws of physics are wrong just because some bored physicists don't have anything to do? That seems to be what Overbye and everyone else are saying.

Tuesday, November 20, 2018

Quantum computing skeptic in IEEE Spectrum

I have long been a skeptic about quantum computing. It is probably the opinion on this blog that is most attacked for being wrong.

IEEE Spectrum mag, the leading journal for electrical engineers, published an article on The Case Against Quantum Computing:
Quantum computing is all the rage. It seems like hardly a day goes by without some news outlet describing the extraordinary things this technology promises. Most commentators forget, or just gloss over, the fact that people have been working on quantum computing for decades — and without any practical results to show for it. ...

On the hardware front, advanced research is under way, with a 49-qubit chip (Intel), a 50-qubit chip (IBM), and a 72-qubit chip (Google) having recently been fabricated and studied. The eventual outcome of this activity is not entirely clear, especially because these companies have not revealed the details of their work.

While I believe that such experimental research is beneficial and may lead to a better understanding of complicated quantum systems, I’m skeptical that these efforts will ever result in a practical quantum computer. Such a computer would have to be able to manipulate — on a microscopic level and with enormous precision — a physical system characterized by an unimaginably huge set of parameters, each of which can take on a continuous range of values. Could we ever learn to control the more than 10300 continuously variable parameters defining the quantum state of such a system?

My answer is simple. No, never.
There are comments here.

IBM and Google were claiming in 2017 that they would have demonstrated quantum supremacy before the end of that year. Now we are almost at the end of 2018, and still no quantum supremacy.

It is rare for a mainstream publication to admit that quantum computing may be impossible. The author is a well-respected physicist.

Monday, November 19, 2018

Public Radio program says we have no free will

I believe in free will, for reasons similar to my belief in consciousness. It is an essential part of everyday human life. It is mostly a philosophical issue, not a scientific one. I only mention it here when someone tries to bring scientific arguments to bear on the issue.

The current episode of Public Radio This American Life is dedicated to denying the existence of free will:
David Kestenbaum: Let me say upfront, I realize the ridiculous, late-night, college-dorm-room nature of what I'm about to say, but here it is. I do not see how free will can exist. By free will, I mean, when you're staring at the menu, and you pick the salad over the burger or any other choice you make-- big or small-- who you marry, whether you keep listening to me for another minute.

Free will is the idea that you really get to pick. I'm saying you don't. I don't see how free will can exist. ...

David Kestenbaum: So you ask this question, can there be free will? But I don't think you directly come out and say what you think. So what do you think?

Robert Sapolsky: I think I was basically trying to be polite there and sort of a good guest. In actuality, I don't think there is room for the slightest bit of free will out there.

David Kestenbaum: Sapolsky said, this was, in fact, the entire reason he had written the book. He was trying to lead people slowly along a gentle path to this uncomfortable idea. I was reading it right.

I asked him why he doesn't believe we have free will. As a neuroscientist, he thinks about it this way. Take any action-- a movement of your eyebrow, something you say. Just trace that thing back. Behind anything like that are just some muscles that moved.
Robert Sapolsky: So let's simplify it. A muscle did something. Meaning a neuron in your motor cortex commanded your muscle to do that. That neuron fired only because it got inputs from umpteen other neurons milliseconds before.

And those neurons only fired because they got inputs milliseconds before and back and back and back. Show me one neuron anywhere in this pathway that, from out of nowhere, decided to say something that activated in ways that are not explained by the laws of the physical universe, and ions, and channels, and all that sort of stuff. Show me one neuron that has some cellular semblance of free will. And there is no such neuron.
David Kestenbaum: Your emotions, consciousness -- same argument. At the bottom, just cells and chemicals acting like they would in the lab.

Robert Sapolsky: There's nothing more or less than the mechanics. ...

For Sapolsky, this idea that we don't have free will is truly profound and should change the way we think about lots of things. For instance, all those decisions you've made because you're a good person, all those things you're proud of-- don't be so proud. Anyone else starting with your atoms in the same place would have done the same thing. ...

David Kestenbaum: I should say, there is some debate about whether no free will means that if you went back in time, and let your life unfold again, you would make all the same decisions exactly the same way. The reason there's some debate is that way down at the subatomic level, there does seem to be a little wellspring of randomness.

Quantum mechanics is all about probabilities. Like when a radioactive atom breaks apart, the exact moment it happens seems random. It's unclear how often this apparent subatomic randomness escapes into the larger world. But it could be that if you rewound the film of life and played it forward again, you might get a different movie. But it wouldn't be because of free will. It would just be subatomic randomness messing with the plot. ...

Special thanks today to Rob Long, Kelefa Sanneh, Stu Greenberg, Sean Carroll, Jim Naureckas, Charlie Schaupp, Stephen Talbot.
The funny thing about this is that they consulted physicists Melissa Franklin and Sean M. Carroll who told them about quantum randomness, but who failed to set them straight.

Sapolsky is a big shot Stanford professor who wrote a fat book on how genetics and environmental conditioning can influence as much as 80% of human behavior. As an example, he explains how advertising can condition consumers to buy a product.

I accept that. Free will concerns only 20% of behavior, maybe.

It is funny how this pseudo-scientific arguments against free will go. First they give some 19th century argument for determinism, based on a mechanistic model of the universe. Then they explain how quantum mechanics proved that the argument is wrong, and that human determinism appears to be false. But then they go back to arguing their mechanistic determinism anyway to conclude that science shows that there is no free will.

Franklin says we appear to have free will, but that must be wrong because she cannot reconcile it with 19th century determinism.

If Kestenbaum, Sapolsky, and Carroll say that they have no free will, perhaps I should believe them. I have known lots of very high IQ professor who, when asked about politics or religion, sound like NPC automatons. They do not appear to have freely chosen their most cherished beliefs. Faced with that, maybe it makes sense for them to doubt free will.

But claiming that some scientific argument for determinism proves that no one has free will is a crackpot idea.

I enjoy This American Life radio, but they should have been able to find a scientist to defend free will.

Here is Sapolsky, from a previous Public Radio program:
SAPOLSKY: Well, just to really take us into (laughter) potentially not-touch-with-a-10-foot-pole territory, my personal bias is we've got no agency at all. I don't think there's a shred of free will out there. From spending my decades thinking about behavior and the biological influences on it, I'm convinced by now free will is what we call the biology that hasn't been discovered yet. It's just another way of stating that we're biological organisms determined by the physical laws of the universe.

RAZ: So everything that you're saying here now and everything that I'm saying to you now and the things I'm going to do for the rest of the day and that you're going to do for the rest - and the interactions you're going to have and I'm going to have, we have very little say in that?

SAPOLSKY: Actually, remarkably little sort of conscious access to it. An awful lot of the time, say, if we choose a behavior, it turns out there was some subterranean emotional tumult that led to that.
Again, his argument is based on assuming that the physical laws of the universe are deterministic, and that evidence of partial biological influence is really partial evidence of total biological determination.

Update: Biology professor Jerry Coyne agrees with these anti-free-will views, and writes:
Unless you don’t accept the laws of physics, the only kind of free will we can have is one compatible with the laws of physics, which denies us dualistic agency. Carroll is in fact a strict determinist, and his version of free will is compatibilist: “the free will that we use as shorthand for feeling like agents although we really obey the laws of physics.” ...

It was inevitable that Mao and Hitler murdered millions given their genes and environments and the laws of physics. But that doesn’t mean they shouldn’t be punished. Punishment is absolutely compatible with hard determinism because it deters people, sequesters bad people, and can help reform bad people. I have written about this many times on this site.
I accept the laws of physics, but those laws are not deterministic.

I don't see how physicists like Franklin and Carroll can be strict determinists, when the laws of physics are not. I also don't see the point to helping reform bad people who do not have free will.

Wednesday, November 14, 2018

Close orbit to Milky Way black hole

The Bad Astronomer (aka Phil Plait) writes:
Because in the paper, a team of astronomers show that they have observed a blob of dust sitting just outside the point of no return of a supermassive black hole, where the gravity is so intense that this material is moving at thirty percent the speed of light. And this wasn’t inferred, deduced, or shown indirectly. No: They measured this motion by literally seeing the blobs move in their observations. ...

Sitting in the exact center of the Milky Way is a supermassive black hole… and astronomers don’t use that adjective lightly. It has a mass over 4 million times that of the Sun, and all of that is squeezed down into a spherical region of space only 20 million kilometers across. The Sun itself is over a million kilometers across, so this is a tiny volume for all that mass. The gravity of such a beast is so immense that if you get too close, you cannot escape. Not even light, which travels at the fastest possible speed in the Universe, can get out. It’s like a dark extremely massive infinitely deep hole. ...

Their motions can be directly seen, and one, called S2, circles the center on an orbit just 16 years long, taking it to within a breathtaking 18 billion kilometers of the exact center.

Using Kepler’s laws of motion, the shapes and periods of the stars’ orbits can be used to find the mass of the object they orbit, and that’s where the 4 million solar mass figure comes from. Yet we see nothing emitting light there, no huge object, no star cluster. It really must be a black hole. Anything else would be extremely bright.
This is interesting, but it really doesn't much to do with relativity.

The way relativity is usually described, a black hole is a singularity, and not "a spherical region of space only 20 million kilometers across". The distance across is infinite. Or as BA says, "a dark extremely massive infinitely deep hole." And nothing comes within any finite distance of "the exact center", because the exact center is the singularity, with infinite distance to everything.

So I am surprised that BA talks about black holes as if they can exist in Euclidean geometry, without a singularity.

We don't see inside the black hole, so we don't really know. On the outside, it looks spherical. The above paper just describes a plain old Keplerian orbit as it might have been understood four centuries ago. Just one involving bigger masses and faster speeds than has been seen before. We don't see any light from the central mass, but that is just what would have been expected two centuries ago.

It is to BA's credit that he does not lecture us on how this confirms Einstein's view of black holes.

Monday, November 12, 2018

Horgan interviews Maudlin

John Horgan interviews philosopher Tim Maudlin for SciAm. I sometimes trash philosophers, including Maudlin, so I will emphasize where I agree with him.
Filmmaker Errol Morris hates Thomas Kuhn. What’s your take on Kuhn?

The Structure of Scientific Revolutions contains some nice observations on the nature of what Kuhn calls “normal science”, which makes it out to have none of the heroic aspects that Popper insisted on. But when Kuhn goes beyond normal science to “revolutionary science” the book is a disaster. It promotes an irrationalist view of scientific revolutions that is both false and pernicious.
Exactly correct. Kuhn's popularity is a large part of why I trash philosophy of science.
Overwhelmingly most philosophers are atheists or agnostics, which I take to be convergence to the truth. Most are compatibilist about free will and believe in it, which I also take to be convergence to the truth. Almost all believe in consciousness and most don’t have a clue how to explain it, which is wisdom.
This is reassuring.
What’s your take on multiverses and strings and the problem of testability?

Some people have been mesmerized by fancy math. It is not interesting physics in my view, and has had a very, very bad effect on the seriousness of theoretical physics as practiced.
Does Gödel’s incompleteness theorem have implications beyond mathematics? Is it a worm in the apple of rationality?

No. Absolutely no one should have ever been surprised that mathematical truth cannot be equated with theoremhood in some finite axiomatic system.
Again, I agree. Godel's theorem is fascinating and profound for logic and the foundations of mathematics, but nearly all applications outside math in the popular literature are nonsense.

He lost me with his favorite interpretation of quantum mechanics. I have discussed that elsewhere. He also lost me with this:
What’s your position on the status of ethics? Do any moral rules have the same status as mathematical truths? Do you believe in moral progress?

Yes (with qualification) and yes. Already in Republic (Plato again!) we have an argument — a clear and compelling rational argument — that even the highest political office should be open to women. The argument? List what it takes to be a good leader of the state, then note the conditions that distinguish the sexes. There just is zero overlap between the two lists. That is as compelling as a rational argument can be, and it follows that opening all political offices to women (much less acknowledging in law that women should have as much right to vote as men) is objective moral progress. Similarly for invidious legal restrictions by race. The civil rights movement was strict moral progress. That’s as true as 2 + 2 = 4.
Wow. Because of some logical, almost mathematical argument, known to Plato, someone like Hillary Clinton should be President of the USA?!

Donald Trump has that list of qualities. Fearless. Honest. Loyal. Blunt. Likable. Strength of character. True to his word. Alpha. Not intimidated by his enemies. Maintain hundreds of friendships and political alliances. Forceful. Smart. Competent. Just enough of a narcissist Machiavellian sociopath to be effective. Strong moral compass. Unflinching about sticking up for the people he represents. Vision for a better future. Communicates his ideas well. Owned by no one. Shitlord.

Neither Hillary Clinton nor any other woman has these qualities.

Maudlin is probably a typical academic leftist Trump-hater who voted for Hillary Clinton, so I am sure he disagrees. But I do wonder about his list of what it takes to be a good leader of the state. Is there really such a list where Donald Trump and Hillary Clinton do equally well?

Maybe Maudlin is making a joke here. He would probably be ostracized from his profession if he openly supported Trump.

When the thought-control police are forcing you to take a political stand, sometimes the best way is to give an argument that is so unreasonable that no one could take it seriously. Maybe Maudlin is doing that here, and trolling us. Can he really think that supporting Hillary Clinton is like 2 + 2 = 4?

He says he believes in free will. At least he says he believes Brett Cavanaugh has free will. We don't want any more pre-programmed automatons on the Supreme Court, do we? Did he say Cavanaugh has free will as a sneaky way of supporting him?

I should just agree with his arguments that made sense, and not try to decode his political sarcasm. I don't like to get political on this blog anyway.

Saturday, November 10, 2018

Physics rejects counterfactual definiteness

Lubos Motl rants, as part of a defense of string theory:
People enjoying terms such as the "counterfactual definiteness" have two main motivations. One of them is simply their desire to look smart even though almost all of them are intellectually mediocre folks, with the IQ close to 100. This category of people greatly overlaps with those who like to boast about their scores from IQ tests – or who struggle for 10 years to make a journal accept their crackpot paper, so that they can brag to be finally the best physicists in the world (I've never had a problem with my/our papers' getting published). The other is related but more specific: "counterfactual definiteness" was chosen to represent their prejudices that Nature obeys classical physics – which they believe and they're mentally unable to transcend this belief.

If something is called "counterfactual definiteness", it must be right, mustn't it? The person who invented such a complicated phrase must have been smart, listeners are led to believe, so the property must be obeyed in Nature. Wouldn't it otherwise be a giant waste of time that someone invented the long phrase and wrote papers and books about it? Sorry, it's not obeyed, the awkward terminology cannot change anything about it, the people who enjoy using similar phrases have the IQ about 100 and they are simply not too smart, and indeed, all the time was wasted.
He is correct that counterfactual definiteness is not obey in Nature, but I doubt that he is right about the term being invented to trick low-IQ ppl into falling for a false concept.

Believing in counterfactual definiteness is like believing in Many-Worlds. It literally means that your counterfactual fantasies have some definite reality. Things that never happened can be discussed as if they did.

Technically, nothing is really definite in Many-Worlds, so maybe it is not the best example. Newtonian mechanics is a better example of counterfactual definiteness.

It is opposite the more conventional quantum mechanical view that "unperformed experiments have no results". You cannot analyze the double-slit experiment by assuming that particles definitely went thru one slit or the other. If you do, then you don't see an interference pattern. We see the interference pattern, so counterfactual definiteness is wrong.

The essence of Bell's Theorem is that assuming counterfactual definiteness leads to conclusions that contradict quantum mechanics. The sensible conclusion is that counterfactual definiteness is wrong. There are some other possibilities, but they require rejecting more basic scientific principles.

Thinking sensibly about counterfactuals is the key to understanding quantum mechanics. Many of the paradoxes that make it hard to understand quantum mechanics are based on attributing some faulty meaning to a counterfactual.

Thursday, November 8, 2018

Astronomers excited about black holes

NY Times science writer Dennis Overbye writes about the black hole at the center of the Milky Way.

The article mentions Einstein ten times, even tho he had almost nothing to do with the concept.

Black holes were first proposed in 1784. The relativistic equations for a black hole were found by Schwarzschild and a student of Lorentz's, but many mistakenly thought that there was a singularity on the event horizon. Some modern theoretical physicists still think that there is such a singularity, in order to preserve their intuition about information emerging from evaporating black holes.

Much as I like to see relativity research research, the astronomy work on black holes does not have much to do with relativity.
Black holes — objects so dense that not even light can escape them — are a surprise consequence of Einstein’s general theory of relativity, which ascribes the phenomenon we call gravity to a warping of the geometry of space and time.
Not really. Since 1784 it has been understood that if gravitational force obeys an inverse square law, and the mass is sufficiently concentrated, then the escape velocity will exceed the speed of light and a black hole results.

Relativity does predict some strange things inside the event horizon of a black hole, but relativity also teaches that none of that is observable, so we will never know. There is no proof that there is any sort of singularity.

While general relativity is commonly described as explaining gravity as the warping of the geometry of space and time, that was not Einstein's view. He denounced this geometrical interpretation. And he did not believe in black holes.
“The road is wide open to black hole physics,” Dr. Eisenhauer proclaimed.
It is true that we are getting a lot more info about black holes. A few decades ago we were not even sure that they exist, and now they are crucial for theories of galaxy formation, for explaining the brightest objects in the universe, and for studying gravity waves.

But all that stuff about singularities, entropy, evaporation, firewalls, information conservation, and quantum gravity are completely out of reach.

Monday, November 5, 2018

Leaving true physics to wither

Bee quotes this NY Times article:
“Unable to mount experiments that would require energies comparable to that of the Big Bang genesis event, Dr. Chodos believes, growing numbers of physicists will be tempted to embrace grandiose but untestable theories, a practice that has more than once led science into blind alleys, dogma and mysticism.

In particular, Dr. Chodos worries that “faddish” particle physicists have begun to flock all too uncritically to a notion called “superstring theory.” […] Deprived of the lifeblood of tangible experiment, physicists will “wander off into uncharted regions of philosophy and pure mathematics,'' says Dr. Chodos, leaving true physics to wither.””
This was conventional wisdom among a lot of physicists in the 1970s. I remember hearing a lecture in the late 1970s explaining the exponentially increasing cost of particle accelerators, and how they will never get to the energies that they need to resolve the questions that they are really interested in. Finding some unified field theory would be a miracle of good luck.

It was known back then that even if susy had merit, there would be dozens of free parameters that would be hopeless to determine experimentally. The string theorists decided that they determine them by pure theory instead. By the year 2000 or so, it was established that the plan would never work.

Bee just wrote a book on how theoretical physics has lost its way, but it has been lost for 40 years

Thursday, November 1, 2018

Philosopher defends Many-Worlds

I mentioned the failure of many-worlds, but in fairness, here is a new philosophy paper with another view:
We defend the many-worlds interpretation of quantum mechanics (MWI) against the objection that it cannot explain why measurement outcomes are predicted by the Born probability rule. We understand quantum probabilities in terms of an observer's self-location probabilities. We formulate a probability postulate for the MWI: the probability of self-location in a world with a given set of outcomes is the absolute square of that world's amplitude.
There is no world's amplitude. This paper is just nonsense.

If MWI really predicted probabilities, or predicted any measurement outcomes, you would not need philosophy papers like this.

The whole point of every other scientific theory is to predict outcomes. If MWI does not, then what is it doing for you?

The paper claims that MWI can make predictions, but it is just a stupid hand wave. There are no physics papers that use MWI to predict and experimental outcome.

Monday, October 29, 2018

Creating the First Quantum Internet

Here is the misguided attempt at quantum crypto:
Scientists in Chicago are trying to create the embryo of the first quantum internet. If they succeed, the researchers will produce one, 30-mile piece of a far more secure communications system with the power of fast quantum computing. From a report:
The key was the realization of an unused, 30-mile-long fiber optic link connecting three Chicago-area research institutions -- Argonne National Lab, Fermi Lab and the University of Chicago. This led to the idea to combine efforts and use the link for what they call the Chicago Quantum Exchange. David Awschalom, an Argonne scientist and University of Chicago professor who is the project's principal investigator, tells Axios that the concept is difficult to grasp, even for experts.
MIT Technology Review elaborates:
The QKD approach used by Quantum Xchange works by sending an encoded message in classical bits while the keys to decode it are sent in the form of quantum bits, or qubits. These are typically photons, which travel easily along fiber-optic cables. The beauty of this approach is that any attempt to snoop on a qubit immediately destroys its delicate quantum state, wiping out the information it carries and leaving a telltale sign of an intrusion. The initial leg of the network, linking New York City to New Jersey, will allow banks and other businesses to ship information between offices in Manhattan and data centers and other locations outside the city.
However, sending quantum keys over long distances requires "trusted nodes," which are similar to repeaters that boost signals in a standard data cable. Quantum Xchange says it will have 13 of these along its full network. At nodes, keys are decrypted into classical bits and then returned to a quantum state for onward transmission. In theory, a hacker could steal them while they are briefly vulnerable.
This is really foolish. We have cheap reliable end-to-end encryption that has not been broken.

The quantum crypto methods are unable to offer similar assurances. They cannot authenticate messages. They cannot do end-to-end encryption, so they require trusted nodes. They are subject to hardware faults, and such faults have been used to break all the commercial equipment.

The big advantage of the quantum crypto is that you are supposed to be able to shut down the network if you detect a probability of an attack. Who wants that? The whole point of the real internet is to always transmit traffic, regardless of problems. The quantum internet will shut down at the first sign of a problem.

The whole idea of a quantum internet is a scam.

Saturday, October 27, 2018

Stop doing fundamental physics

Lubos Motl writes:
The video starts boldly:
I will talk about string theory not because I think it's interesting but because it's uninteresting and we should stop talking about it.
Holy cow. String theory remains the only game in town and everyone who wants to scientifically investigate any physical phenomena that go beyond effective quantum field theories – whose limitations are self-evident and well-known – simply must learn string/M-theory. There is no known alternative. To "stop talking about it" is almost exactly equivalent to stop doing fundamental physics. ...

On the other hand, Hossenfelder clearly doesn't have any alternative to string theory. She doesn't have any quantum mechanical theory that agrees with Einstein's equations at long distances but preserves the information when the black hole evaporates. But she – and her brain-dead followers – just don't care.
Yeah, I just don't care about such a theory.

Einstein's equations at long distances are the same as for Newtonian gravity. Either way, you can add dark energy, altho, as Bee explains, much of string theory was based on dark energy being negative, and we now know that it is positive.

But string theory preserves the info when a black hole evaporates? That is just nonsense. It makes more sense to talk about the Biblical apocalypse.

Maybe fundamental physics should stop. It is going nowhere. All that brainpower could be put to more productive purposes.

Wednesday, October 24, 2018

Krauss pushed into retirement

I posted before about physicist Lawrence Krauss being silenced.

BuzzFeed brags that it has hounded a physicist out of academia:
Lawrence Krauss, the celebrity physicist who faced dismissal from Arizona State University for violating sexual misconduct policy, has agreed to step down from the school.

In statements posted on Facebook and Twitter on Sunday, Krauss said: “I have chosen to retire from ASU in May, 2019, when I turn 65.”
I am not going to pile on here. I believe he is innocent until proven guilty. Among the accusations are that he made "sexist comments".

Krauss has written some worthwhile popular physics books. If I were going to be offended by his comments, then I would probably be offended by his leftist political views. Making sexist comments is not a crime. Not yet.

Saturday, October 20, 2018

Explaining the failure of Many-Worlds

Philip Ball explains what is wrong with the Many Worlds Interpretation of quantum mechanics:
The MWI is qualitatively different from the other interpretations of quantum mechanics, although that’s rarely recognized or admitted. For the interpretation speaks not just to quantum mechanics itself but to what we consider knowledge and understanding to mean in science. It asks us what sort of theory, in the end, we will demand or accept as a claim to know the world. ...

What the MWI really denies is the existence of facts at all. It replaces them with an experience of pseudo-facts (we think that this happened, even though that happened too). In so doing, it eliminates any coherent notion of what we can experience, or have experienced, or are experiencing right now. We might reasonably wonder if there is any value — any meaning — in what remains, and whether the sacrifice has been worth it. ...

It says that our unique experience as individuals is not simply a bit imperfect, a bit unreliable and fuzzy, but is a complete illusion. If we really pursue that idea, rather than pretending that it gives us quantum siblings, we find ourselves unable to say anything about anything that can be considered a meaningful truth. We are not just suspended in language; we have denied language any agency. The MWI — if taken seriously — is unthinkable. ...

What quantum theory seems to insist is that at the fundamental level the world cannot supply clear “yes/no” empirical answers to all the questions that seem at face value as though they should have one. The calm acceptance of that fact by the Copenhagen interpretation seems to some, and with good reason, to be far too unsatisfactory and complacent. The MWI is an exuberant attempt to rescue the “yes/no” by admitting both of them at once. But in the end, if you say everything is true, you have said nothing.
That's right. Ultimately MWI says nothing that you would want from a scientific theory. There are no facts, predictions, or confirming experiments.

MWI just says that everything that can happen does happen in some parallel world. It allows you to think and believe whatever you want. Probabilities are meaningless. Reality and facts are meaningless.

MWI is just the same as the child's fantasy. The proponents give the impression that it is a scientific theory that gives a detailed explanation of the worlds, with Hilbert space, wave function, Schroedinger equation, atomic forces, etc. Yes, but none of them can explain how all that apparatus tells you anything beyond the simplistic child's fantasy. There are no predictions or confirming experiments.

I used to to think that string theory was the epitome of unscientific thinking. But string theory is vastly more reasonable that MWI. String theory at least had some hope of getting some theoretical explanations. MWI explains nothing, and discards almost everything we know about science.

Update: LuMo writes:
Now, Ball has written a text about some conceptual and basically insurmountable problems of the "many-world interpretation" paradigm sometimes used to misinterpret quantum mechanics. Among other things, he focused on the impossibility to define what a "splitting of the Universes" is and when and how many times it takes place. This is of course one of the problems about MWI that I see and often write about – but there are others, too. ...

However, the comment sections are frustrating. Both articles have attracted over 100 comments by now. Pretty much all the most upvoted comments attack Wolchover's and Ball's texts. You can see that none of these people actually understands quantum mechanics and all of them assume that classical physics is right throughout their comments and lives.
I had not noticed that Quanta mag allows comments, because my adblocker blocks them.

I would not bother criticizing MWI, except that it has such a huge following, from leading physicists on down to the general public. Here is one of the dopey comments:
The fact is that the MWI is strictly adherent to the mathematics of quantum physics. There is no extra phenomenon like "observation" (that's just entanglement) there is no extra phenomenon like "waveform collapse" the entangled particle becomes part of a more complex waveform.

MWI doesn't have to justify adding any additional complexity to QM because it doesn't. Copenhagen, Pilot Wave, et. al. are the interpretations that add extra complexity that don't show up in the math, so they're the ones that have to justify that complexity. What the hell is an observer? What the hell is waveform collapse?
MWI doesn't have to define observers because it does not make any predictions.

The math of quantum physics makes predictions that are verified by experiments. MWI makes no such predictions. Therefore MWI does not adhere to the math of quantum physics.

Thursday, October 11, 2018

The decline of relativistic mass

Vesselin Petkov notes how the concept of "relativistic mass" has gone out of fashion:
These facts make the campaign against the concept of relativistic mass both inexplicable and worrisome. Instead of initiating and stimulating research on the origin of relativistic mass (and on the nature of mass in general) in order to achieve a more profound understanding of this fundamental concept in physics,7 the relativistic mass is not mentioned at all in many publications8 (see, for example, the well-known textbook [35]) or, if it is mentioned, it is done to caution the readers9, that "Most physicists prefer to consider the mass of a particle as fixed" [25, p. 760], that "Most physicists prefer to keep the concept of mass as an invariant, intrinsic property of an object" [32], that "We choose not to use relativistic mass, because it can be a misleading concept" [36] or to warn them [22, p. 1215]:
Watch Out for "Relativistic Mass"

Some older treatments of relativity maintained the conservation of momentum principle at high speeds by using a model in which a particle's mass increases with speed. You might still encounter this notion of "relativistic mass" in your outside reading, especially in older books. Be aware that this notion is no longer widely accepted; today, mass is considered as invariant, independent of speed. The mass of an object in all frames is considered to be the mass as measured by an observer at rest with respect to the object.
As he explains, this opinion is pretty arbitrary, and relativistic mass is analogous to length contraction or time dilation. Yes, it depends on the frame, and it can be a little confusing, but that's relativity.

Wednesday, October 10, 2018

Biologist defends de-publishing papers

Computational biology professor Lior Pachter writes:
In the case discussed in this blog post, the underlying subtext is pervasive sexism and misogyny in the mathematics profession, and if this sham paper on the variance hypothesis had gotten the stamp of approval of a journal as respected as NYJM, real harm to women in mathematics and women who in the future may have chosen to study mathematics could have been done. It’s no different than the case of Andrew Wakefield‘s paper in The Lancet implying a link between vaccinations and autism. By the time of the retraction (twelve years after publication of the article, in 2010), the paper had significantly damaged public health, and even today its effects, namely death as a result of reduced vaccination, continue to be felt.
He and his liberal colleagues have a funny idea of what science is all about.

Wakefield's paper did not damage public health. It merely suggested a health concern, based on some very limited data. The proper response would have been to do a more thorough study on measles vaccine safety.

Instead the medical authorities blamed Wakefield for reduced confidence in vaccination, so they retracted the paper and stripped Wakefield of his medical license.

Those who suspected a cover-up of vaccine risks had their suspicions confirmed. Nobody would every publish anything critical of vaccines again, or risk losing his medical license.

Pachter points out that papers on the evolution of sex differences go back to 1895, at least. So how is it that publishing another one will do real harm to women in mathematics? Pachter doesn't actually explain what is wrong with the paper, except that it is politically incorrect and fails to cite some previous work on the subject.

I do not get confidence in vaccines by having a ban on papers describing vaccine dangers. And I do not think that women should get encouragement in math by banning papers on variance in mathematical ability.

Sunday, October 7, 2018

Claiming quantum mechanics is inconsistent

These is whole industry of physicists working in quantum foundations who make various arguments that quantum mechanics doesn't make any sense. They can't deny that quantum mechanics correctly predicts experiments, and yet they keep coming up with clever sleight-of-hand thought experiments and paradoxes that supposedly show that the theory does not work.

The whole enterprise is foolish. If there were really such contradictions, then there would be some failure to predict experiments.

Scott Aaronson pauses from his agony of being a Jewish leftist Trump-hating professor in a red state to explain:
So: a bunch of people asked for my reaction to the new Nature Communications paper by Daniela Frauchiger and Renato Renner, provocatively titled “Quantum theory cannot consistently describe the use of itself.” Here’s the abstract:
Quantum theory provides an extremely accurate description of fundamental processes in physics. It thus seems likely that the theory is applicable beyond the, mostly microscopic, domain in which it has been tested experimentally. Here, we propose a Gedankenexperiment to investigate the question whether quantum theory can, in principle, have universal validity. The idea is that, if the answer was yes, it must be possible to employ quantum theory to model complex systems that include agents who are themselves using quantum theory. Analysing the experiment under this presumption, we find that one agent, upon observing a particular measurement outcome, must conclude that another agent has predicted the opposite outcome with certainty. The agents’ conclusions, although all derived within quantum theory, are thus inconsistent. This indicates that quantum theory cannot be extrapolated to complex systems, at least not in a straightforward manner.
The paper authors separately argue that this proves the many-world interpretation.

That conclusion should be enuf to dispose of the argument. The MWI does not predict any experimental outcomes. There is nothing scientific about it. It is like some solipsist saying anything can happen in his imagination.

Aaronson explains the errors in more detail. So does Lubos Motl. Somehow this paper got published in a Nature journal. It has become respectable to trash quantum mechanics with silly arguments.