Monday, October 31, 2016

Academics endorse Democrats

I used to think that universities had the smartest ppl. But if they were really intelligent, then they would be able to think independently.

On political subjects especially, they just mindlessly recite what they have been told.

Just today, I see Scott Aaronson and Peter Woit urging votes against Donald Trump.

Woit writes:
There’s little evidence Trump has fixed views on any policy issue ...

Most damaging though is the behavior of the mainstream media, in particular that of the New York Times, whose coverage of this issue has been atrociously unfair to Clinton.
Trump is hated for his views. If you do not know what they are, then you are not paying attention.

I read the NY Times, and it prints crazy attacks on Trump every day. It might call him a Nazi, or complain that he refuses to concede the election, or bring up a recording of a private conversation 20 years ago where he uses the word f*ck, or some such nonsense.

The stories about Hillary Clinton have a direct bearing on her corruption and bad judgment in public office.

Hardly anyone can even make an argument for Clinton without mentioning Trump. 70 Nobel prize (and Bank of Sweden prize) winners attempted:
To preserve our freedoms, protect our constitutional government, safeguard our national security, and ensure that all members of our nation will be able to work together for a better future, it is imperative that Hillary Clinton be elected as the next President of the United States. ...

We need a President who will support and advance policies that will enable science and technology to flourish in our country and to provide the basis of important policy decisions.
Really? These are not reasons that would persuade anyone. Clinton and Trump hardly have any differences in science and technology policy.

Obviously the Nobel and economics prize winners are not telling us their real reasons.

Hardly anyone is able to explain some agreement with some actual Clinton policy or decision.

I remember in 2008, all these brilliant scientists told us that we had to elect Barack Obama because he was going to fund stem-cell research that was going to have paralyzed ppl walking again in about 2 years. It was just a big lie. It is now 8 years later, and no medically useful treatments have come out of that research at all.

Update: Lubos Motl piles on. It is funny when his rants make more sense than the opinions of big-shots.

Friday, October 28, 2016

In search of Quantum Supremacy

Computer complexity theorist had 5 minutes to explain quantum computers, and said:
But what quantum supremacy means to me, is demonstrating a quantum speedup for some task as confidently as possible.  Notice that I didn’t say a useful task!  I like to say that for me, the #1 application of quantum computing — more than codebreaking, machine learning, or even quantum simulation — is just disproving the people who say quantum computing is impossible!  So, quantum supremacy targets that application.

What is important for quantum supremacy is that we solve a clearly defined problem, with some relationship between inputs and outputs that’s independent of whatever hardware we’re using to solve the problem.  That’s part of why it doesn’t cut it to point to some complicated, hard-to-simulate molecule and say “aha!  quantum supremacy!”
I accept this, but the important points is that quantum supremacy has never been demonstrated. Yes, there are regular press releases and news stories about advances in new and better quantum computers, but no one has ever shown a quantum speedup over regular Turing computers.

Charles H. Bennett responds:
An experimental demonstration of what is infelicitously called quantum supremacy (I prefer “classical retardation”) would be way less earthshaking than the Higgs boson. It would be much more like the experimental demonstrations of Bell and CHSH violations: a validation of what we have every right to expect, based on the unblemished success of quantum theory so far.
I do not agree. Quantum theory is unblemished in confirming Bell violations, yes, but the computational speedups are speculative and have not been shown. I doubt that they will ever be shown.

Monday, October 24, 2016

It is not Ptolemy

Statistician Andrew Gelman has done some good work debunking shoddy social science about the "power pose":

I don’t care about power pose. It’s just a silly fad. I do care about reality, and I care about science, which is one of the methods we have for learning about reality. The current system of scientific publication, in which a research team can get fame, fortune, and citations by p-hacking, and then even when later research groups fail to replicate the study, that even then there is the continuing push to credit the original work and to hypothesize mysterious interaction effects that would manage to preserve everyone’s reputation . . . it’s a problem.

It’s Ptolemy, man, that’s what it is. [No, it’s not Ptolemy; see Ethan’s comment below.]

Okay, I won't criticize him much, because he did correct himself. But obviously he was relying on a popular stereotype that equates Ptolemy with bad science.

A comment says:
Why the knock on Ptolemy? His epicicyle model made predictions verifiable with the measurement methods of his time. There will be no Kepler to update the power pose.

Epicyclical motion is used in the Antikythera mechanism, an ancient Greek astronomical device for > compensating for the elliptical orbit of the Moon, moving faster at perigee and slower at apogee than circular orbits would, using four gears, two of them engaged in an eccentric way that quite closely approximates Kepler’s second law.

As an indication of exactly how good the Ptolemaic model is, modern planetariums are built using gears and motors that essentially reproduce the Ptolemaic model for the appearance of the sky as viewed from a stationary Earth.
Mocking Ptolemy is like mocking modern planetariums. It shows a very bizarre view of what science is all about.

Ptolemy and Kepler were two of the greatest scientific geniuses of all time. A recent paper on Galileo (1564-1642) and Kepler (1571-1630):
the modern scientist and the mystic
points out that Kepler is also underrated, compared to Galileo.
Perhaps the most instructive example of a clash between Galileo's smooth "rational thinking" and Kepler's "mysticism" is provided by their different approaches to the theory of tides. In 1616 Galileo published (in Italian) his Discorso on the topic. In his view, it provided The decisive proof that the Earth moves [S], p. 224 (the idea having come to him in a flash on one of his frequent trips from Padua to Venice in a
large barge whose bottom contained a certain amount of water). Kepler had the right intuition that the tides are caused by the moon's attraction - a view confirmed and further elaborated by Newton and Laplace of the next generations.
Update: Gelman followed up with another strange attack on Ptolemy, referring to some faulty research:
I call this reasoning Ptolemaic because it’s an attempt to explain an entire pattern of data with an elaborate system of invisible mechanisms.
So I won't credit him for understanding his mistake.

Many outstanding theories of science, such as all field theories, rely on a system of invisible mechanisms. I thought that Gelman started out in Physics, but he badly misunderstands what theoretical science is all about.

Saturday, October 22, 2016

Brain entropy said to explain consciousness

PhysicsWorld reports:
Consciousness appears to arise naturally as a result of a brain maximizing its information content. So says a group of scientists in Canada and France, which has studied how the electrical activity in people's brains varies according to individuals' conscious states. The researchers find that normal waking states are associated with maximum values of what they call a brain's "entropy". ...

The latest work stems from the observation that consciousness, or at least the proper functioning of brains, is associated not with high or even low degrees of synchronicity between neurons but by middling amounts. Jose Luis Perez Velazquez, a biochemist at the University of Toronto, and colleagues hypothesized that what is maximized during consciousness is not connectivity itself but the number of different ways that a certain degree of connectivity can be achieved.

Perez Velazquez's colleague Ramon Guevarra Erra, a physicist at the Paris Descartes University, points out that there is only one way to connect each set of neurons in a network with every other set, just as there is only one way to have no connections at all. In contrast, he notes, there are many different ways that an intermediate medium-sized number of connections can be arranged.

To put their hypothesis to the test, the researchers used data previously collected by Perez Velazquez showing electric- and magnetic-field emissions from the brains of nine people, seven of whom suffered from epilepsy. ...

Perez Velazquez and colleagues argue that consciousness could simply be an "emergent property" of a system – the brain – that seeks to maximize information exchange and therefore entropy, since doing so aids the survival of the brain's bearer by allowing them to better model their environment.
Maybe consciousness is an emergent property. Maybe it can be related to how neurons form connections. Maybe these researchers are on to something. But calling it brain entropy seems like a stretch.

Brain entropy said to explain consciousness

PhysicsWorld reports:
Consciousness appears to arise naturally as a result of a brain maximizing its information content. So says a group of scientists in Canada and France, which has studied how the electrical activity in people's brains varies according to individuals' conscious states. The researchers find that normal waking states are associated with maximum values of what they call a brain's "entropy". ...

The latest work stems from the observation that consciousness, or at least the proper functioning of brains, is associated not with high or even low degrees of synchronicity between neurons but by middling amounts. Jose Luis Perez Velazquez, a biochemist at the University of Toronto, and colleagues hypothesized that what is maximized during consciousness is not connectivity itself but the number of different ways that a certain degree of connectivity can be achieved.

Perez Velazquez's colleague Ramon Guevarra Erra, a physicist at the Paris Descartes University, points out that there is only one way to connect each set of neurons in a network with every other set, just as there is only one way to have no connections at all. In contrast, he notes, there are many different ways that an intermediate medium-sized number of connections can be arranged.

To put their hypothesis to the test, the researchers used data previously collected by Perez Velazquez showing electric- and magnetic-field emissions from the brains of nine people, seven of whom suffered from epilepsy. ...

Perez Velazquez and colleagues argue that consciousness could simply be an "emergent property" of a system – the brain – that seeks to maximize information exchange and therefore entropy, since doing so aids the survival of the brain's bearer by allowing them to better model their environment.
Maybe consciousness is an emergent property. Maybe it can be related to how neurons form connections. Maybe these researchers are on to something. But calling it brain entropy seems like a stretch.

Brain entropy said to explain consciousness

PhysicsWorld reports:
Consciousness appears to arise naturally as a result of a brain maximizing its information content. So says a group of scientists in Canada and France, which has studied how the electrical activity in people's brains varies according to individuals' conscious states. The researchers find that normal waking states are associated with maximum values of what they call a brain's "entropy". ...

The latest work stems from the observation that consciousness, or at least the proper functioning of brains, is associated not with high or even low degrees of synchronicity between neurons but by middling amounts. Jose Luis Perez Velazquez, a biochemist at the University of Toronto, and colleagues hypothesized that what is maximized during consciousness is not connectivity itself but the number of different ways that a certain degree of connectivity can be achieved.

Perez Velazquez's colleague Ramon Guevarra Erra, a physicist at the Paris Descartes University, points out that there is only one way to connect each set of neurons in a network with every other set, just as there is only one way to have no connections at all. In contrast, he notes, there are many different ways that an intermediate medium-sized number of connections can be arranged.

To put their hypothesis to the test, the researchers used data previously collected by Perez Velazquez showing electric- and magnetic-field emissions from the brains of nine people, seven of whom suffered from epilepsy. ...

Perez Velazquez and colleagues argue that consciousness could simply be an "emergent property" of a system – the brain – that seeks to maximize information exchange and therefore entropy, since doing so aids the survival of the brain's bearer by allowing them to better model their environment.
Maybe consciousness is an emergent property. Maybe it can be related to how neurons form connections. Maybe these researchers are on to something. But calling it brain entropy seems like a stretch.

Brain entropy said to explain consciousness

PhysicsWorld reports:
Consciousness appears to arise naturally as a result of a brain maximizing its information content. So says a group of scientists in Canada and France, which has studied how the electrical activity in people's brains varies according to individuals' conscious states. The researchers find that normal waking states are associated with maximum values of what they call a brain's "entropy". ...

The latest work stems from the observation that consciousness, or at least the proper functioning of brains, is associated not with high or even low degrees of synchronicity between neurons but by middling amounts. Jose Luis Perez Velazquez, a biochemist at the University of Toronto, and colleagues hypothesized that what is maximized during consciousness is not connectivity itself but the number of different ways that a certain degree of connectivity can be achieved.

Perez Velazquez's colleague Ramon Guevarra Erra, a physicist at the Paris Descartes University, points out that there is only one way to connect each set of neurons in a network with every other set, just as there is only one way to have no connections at all. In contrast, he notes, there are many different ways that an intermediate medium-sized number of connections can be arranged.

To put their hypothesis to the test, the researchers used data previously collected by Perez Velazquez showing electric- and magnetic-field emissions from the brains of nine people, seven of whom suffered from epilepsy. ...

Perez Velazquez and colleagues argue that consciousness could simply be an "emergent property" of a system – the brain – that seeks to maximize information exchange and therefore entropy, since doing so aids the survival of the brain's bearer by allowing them to better model their environment.
Maybe consciousness is an emergent property. Maybe it can be related to how neurons form connections. Maybe these researchers are on to something. But calling it brain entropy seems like a stretch.

Monday, October 17, 2016

SciAm on relativity in 1911

Here is the first SciAm article on relativity:
“In 1905, came a fundamental and (as the fu-
ture historian will probably say) an epoch-
making contribution in the shape of an unas-
suming and dry-looking dissertation, ‘Con-
cerning the Electro-dynamics of Moving
Bodies,’ by A. Einstein, a Swiss professor of
physics. It appeared in the Annalen der
Physik, the German counterpart of our Philo-
sophical Magazine. It created no sensation at
the time. It was hardly noticed. Yet, at the pres-
ent time, you cannot open a journal devoted
to physics without finding some fresh contri-
bution to the ever-increasing literature on the
subject: Einstein’s Principle of Relativity.
—E. E. Fournier D’Albe”
Scientific American Supplement, November 11, 1911
I think that it is correct that Einstein's 1905 paper was considered no big deal, and that relativity did not start to take off until 1908. By 1911 relativity was huge, and textbooks were starting to appear.

So why did relativity become so popular in 1908-1911, but not 1905-1908? The obvious explanations are (1) Einstein's paper was not appreciated at first, but it was after 3 years, and (2) Einstein's paper was inconsequential, and Minkowski's 1908 paper made relativity popular.

I say that explanation (2) is better. Minkowski's paper was bold, geometric, and rigorous. It was reprinted and distributed widely. The 1911 works were based on Minkowski's theory, not Einstein's. I do not see any proof that Einstein's paper had much influence on the early development of relativity at all. It seems to have influenced Max Planck, but hardly anyone else. Minkowski learned relativity from David Hilbert, Lorentz, and Poincare, not Einstein.

Hermann Minkowski declared in 1908:
The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.
Minkowski died in 1909, but his 1908 paper was the most widely read relativity paper at the time. Nearly all subsequent relativity work was based on Minkowski's formulation, not Einstein's.

It is odd that Einstein's 1905 paper would be credited as being so influential. I cannot find much actual influence at the time. Everyone considered an embellishment of Lorentz's theory, and some called it the Lorentz-Einstein theory. Apparently it persuaded Planck, but not Minkowski or everyone else. It appears that many people, including this SciAm writer, decided years later than the paper must have been influential. But it was not.