Pages

Wednesday, March 29, 2023

Witten Defends String Theory in Interview

Here is a newly-released video on Edward Witten - What are Breakthroughs in Science?.

Of course Witten says that String Theory and M-Theory are the big breakthroughs. He says that M originally stood for "membranes", because a colleague thought that it was a membrane theory, but Witten was skeptical so he abbreviated it to M. He coysishly pretended it stood for Magical or Matrix. If it turned out to be a membrane theory, he would claim credit.

He admits that string theory could never accommodate parity violation, so it was always inconsistent with the Standard Model.

He defends the Landscape and his inability to predict anything from his theories by saying that gravity theory does not predict the length of the Martian year. Also he says his critics do not suggest a competing theory.

Wow, he cannot admit that he is really a mathematician wannabe who happens to like studying the mathematical structures of theories with no physical significance.

Friday, March 24, 2023

Grover's Algorithm may be a Dud

Grover's algorithm is supposed to be one of the great theoretical accomplishments of quantum computers, along with Shor's algorithm.

Now a new paper argues Grover's Algorithm Offers No Quantum Advantage

Scott Aaronson is not impressed:

I haven’t yet read that paper carefully, but have discussed it with some students and colleagues. My current impression is that it’s a mishmash of

(1) well-known observations about the difficulty of seeing a Grover speedup in practice given the overhead of quantum fault-tolerance, and

(2) a completely absurd argument about the Grover problem being “classically solvable with 1 query,” which would of course violate a known lower bound (what they mean is, in a model where you effectively get explicit access to the oracle function … in which case, we’re no longer talking about query complexity at all, and 0 queries suffice! 🙂 )

I don't know. This paper seems devastating to me, if it is right.

Grover's Algorithm is supposed to let you search N items with only &sqrt;N steps, using a quantum computer.

It is usually described as searching a database. But a relational database usually has an index that allows searching in log(N) steps, much faster than the quantum computer.

Quantum computers are supposed to do it without an index. It seems like magic. Useless magic.

Update: Scott Aaronson refutes the new paper here and here. He agrees with this:

Since the current practical infeasibility is well-known, I assumed the paper was observing something fundamental. It was not.
Okay, not news. Everybody already knew Grover's algorithm was a dud.

Wednesday, March 22, 2023

How Internet Crypto can be Broken

Veritasium has a nice video on How Quantum Computers Break The Internet... Starting Now:
A quantum computer in the next decade could crack the encryption our society relies on using Shor's Algorithm.
Some really paranoid people are worried that their communications are being intercepted now, so that the cryptography can be broken in 10-15 years when quantum computers become practical.

The SSL/TLS internet crypto protocols were introduced largely to assure consumers that they credit card numbers are safe. Quantum computers are not really a threat to that, as there are much easier ways to steal credit card numbers.

My guess is that SSL/TLS will still be safe 50 years from now.

Monday, March 20, 2023

2023 FQI Essay Competition

FQI, aka FQXi.org, has a new essay contest:
How Could Science be Different?

OPEN TO SUBMISSIONS | February 28 to April 19, 2023

1st essays to be posted by March 28. ...

In this Competition, we invite creative and thought-provoking essays addressing science itself by considering the questions: To what degree is the science we have today necessarily the way it is, versus contingent on the particular history and human societies in which it originated? What could a science free of prejudice and bigotry have looked like, what can it look like in the future? And how could the process of science be better?

I submitted essays to previous competitions, but the system had two previous defects.
  1. Essays were not anonymous, and judging was largely on the reputation of the author.
  2. Essays were quietly rejected, if the judges thought that something was incorrect.
The prizes often went to friends and acquaintances of the judges. I suspect that my essays were downgraded because of disagreements with opinions on this blog, as opposed to judging the essay itself. I got high ratings in their public forum, but not from the judges.

They have a forum where authors can defend their essays, before judging. I agree with rejecting incorrect essays, but I think that the errors should first be posted on the forum, so that the author can defend the correctness of the essay. I suspect that some essays were rejected when they were not incorrect. The editor disagreed with some opinions or interpretations. Or the judges were mistaken.

This year's contest promises that the judging will be anonymous. This addresses defect (1). Maybe I will submit an essay, and see if anonymity makes a difference. I also wonder if they are looking for woke essays that argue that science needs to free itself from systemic prejudice to do good works and stop oppressing various groups.

Monday, March 13, 2023

The False Promise of Chomskyism

Noam Chomsky is maybe the world's leading intellectual, with huge academic and political followings:
Avram Noam Chomsky[a] (born December 7, 1928) is an American public intellectual: a linguist, philosopher, cognitive scientist, historian,[b] social critic, and political activist. Sometimes called "the father of modern linguistics",[c] Chomsky is also a major figure in analytic philosophy and one of the founders of the field of cognitive science. He is a Laureate Professor of Linguistics at the University of Arizona and an Institute Professor Emeritus at the Massachusetts Institute of Technology (MIT), and is the author of more than 150 books on topics such as linguistics, war, and politics. Ideologically, he aligns with anarcho-syndicalism and libertarian socialism.
He just weighed in the new large language model (LLM) fad in in the NY Times. He has been arguing all his life that language is innately human, and will never be mastered by computers. So has ChatGPT proved him wrong? Of course not. He doubles down on his theories.

Scott Aaronson now works for OpenAI, and has leapt to its defense:

to my mind, Chomsky was nasty and vicious utterly without justification, in the pages of the New York Times no less, in attacking one of the major engineering accomplishments of our time ...

I meant is that there exists a large “old guard” in AI and NLP research that ...

(1) has been bizarrely insulting, dismissive, and hostile toward the mind-boggling engineering achievement represented by large language models,
(2) failed for 60 years to produce any comparable artifact,
(3) idolizes Chomsky and was probably influenced by him more than any other person, and
(4) displays the trademark Chomskyan tactic of “retreat from the empirical,” where even when something succeeds, the success can be breezily dismissed as an unimportant “epiphenomenon” (but the failures are not epiphenomena). ...

On deeper reflection, I probably don’t need to spend emotional energy refuting people like Chomsky, who believe that Large Language Models are just a laughable fad rather than a step-change in how humans can and will use technology, any more than I would’ve needed to spend it refuting those who said the same about the World Wide Web in 1993. Yes, they’re wrong, and yes, despite being wrong they’re self-certain, hostile, and smug, and yes I can see this, and yes it angers me. But the world is going to make the argument for me.

Aaronson views ChatGPT as being like the nerds who get bullied in high school.

Chomsky makes a point out of the ambiguity of t his sentence:

John is too stubborn to talk to.
I tried this on Bing Chat and on some children, to see how they interpret it. I asked them what it means, along with questions like: Is this saying something about John's ability or willingness to talk?

The answers I got from humans were not much different than from Bing Chat. Where there are differences, I cannot be sure who is right. My conclusion is that the sentence is ambiguous and should be corrected by copy editor. It is not an example of good grammar.

In my opinion, the LLMs have mastered English grammar in a way that Chomsky and other naysayers have long said was impossible. They have also captured a vast amount of knowledge and put it in a usable form.

Does Bing Chat actually understand what it is saying? Sabine Hossenfelder says that is like the Feynman remark about nobody understanding quantum mechanics. Sure, lots of people understand it well enough to apply to textbook examples. If you want a deeper metaphysical understanding rivaling your understanding of everyday macroscopic objects, then it is debatable whether such an understanding exists.

In case you are still wondering what the excitement is about, just try it. Bing chat is as much better than Google search, as Google search was better than Alta Vista.

Friday, March 10, 2023

Many Worlds Theory may win an Oscar

The London Guardian celebrates multiverse in Hollywood movies by interviewing Sean M. Carroll. He promotes many-worlds theory, and claims that it is implied by both theory and experiment.

He says that the theory is "super duper testable" and "there is no more falsiable theory than many-worlds". [14:15] But he also says that the multiple universes can have no effect on us, so there cannot be any way of knowing whether they are real or not. There are freaky copies of yourself in parallel universes, but you should not worry about them because they are not truly you.

From his podcast last year:

Every time we make an important decision, it’s hard not to wonder how things would have turned out had we chosen differently. The set of all those hypothetical lives is a kind of “multiverse” — not one predicted by quantum mechanics or cosmology, but a space of possibilities that is ripe for contemplation. In their new movie Everything Everywhere All At Once, Daniels (the collective moniker for writer/directors Daniel Kwan and Daniel Scheinert) use this idea to tell the story of Evelyn (Michelle Yeoh), who is the “worst” of all her avatars in the multiverse. We talk about philosophy, filmmaking, and how we should all strive to be kind amidst the chaos.
In the movie, Evelyn is a Chinese lesbian trying to cope with her parallel selves and her family. Carroll says the movie makers were not inspired by many-worlds theory or cosmology, but simply by other fiction writers who like to imagine alternate possibilities.

A new paper promoting the theory is Many-Worlds: Why Is It Not the Consensus?.

It is hard to believe that these guys sincerely believe the nonsense they are reciting.

The paper says:

Quantum mechanics is known to be resistant to a realist understanding, as it is unclear what picture of reality it provides us. Nonetheless, a variety of realist quantum theories have been proposed, and among these, one finds the many-worlds theory, also known as Everettian quantum mechanics.
No, there is nothing realist about many-worlds. It postulates zillions of non-real parallel universes.
There are various readings of this theory, but they all have in common that all there is in the theory is a quantum state, evolving accord- ing to the Schrödinger unitary evolution equation, which produces experimental results distributed according to the Born rule.
No, many-worlds does not use the Born rule, and does not produce experimental results.

If I say that there is a 1/3 probability of rain today, then it will either rain or not rain. From the info that I have available, 1/3 of the scenarios result in rain.

That is not what the many-worlds folks say at all. They say that rain and no rain both happen. The universe splits into some with rain, and some without rain. Copies of us are in each, thinking that we are in the real universe. There is no way to enumerate the universes or say that anything is more likely than anything else.
Moreover, it is maintained, it is consistent with how physicists use the theory as well as its relativistic extensions. Therefore, one question arises naturally: why is it not the consensus? Why are all people not Everettians?

According to some (Wallace p.c.), Everettian quantum mechanics is the implicit con- sensus, at least among practicing physicists; when they perform calculations, they use the Born rule, ... and they never need to modify the unitary evolution. That is, they implicitly adopt the many-worlds theory.

No. The Born rule is a rule for collapsing the wave function, and is contrary to many-worlds theory.
When informally asked, many of them say that they use standard quantum mechanics, namely the unitary evolution and the collapse rule, rather than unitary evolution alone, and they do not believe that they and their labs are continuously ‘splitting’ into infinitely many worlds. Indeed, some of them will not even see the point of ‘adding’ these worlds on top of the empirical adequacy of the standard theory. If the many-worlds theory makes the same predictions of standard quantum mechanics, but also postulates an infinity of unobservable worlds on top of the one we experience, then why should one prefer this theory to standard quantum mechanics?
That's right.

Many-worlds theory does not make the same predictions. The only prediction it makes is that all things happen in parallel universes. It cannot tell the probability of something happening in one particular universe.

Personally, I favor a constructive explanation of the phenomena, and I think that, if one has such inclinations, the pilot-wave theory should be the clear consensus.
This sentence alone discredits the paper. Pilot-wave theory is a spooky nonlocal theory. It is used as a philosophical example of non-physical interpretation, and that's all. No one uses it. It has no constructive explanation of anything.

Update: This recent paper, for example, admits that the "received view" of many-worlds is that interpreting the Born rule or any other probability is a unsolved problem.

Update: The Chinese lesbian multiverse movie, Everything Everywhere All at Once, won the Best Picture Oscar, as well as a bunch of others.

Monday, March 6, 2023

Science Magazine Favors Physician Racial Brainwashing

AAAS Science has an article in favor of forced racial brainwashing:
Do no unconscious harm
Researchers are finding new ways to mitigate implicit bias in health care providers

Getting buy-in from whole health care systems could accelerate the process. Recently, California, Michigan, Maryland, Minnesota, and Washington state passed legislation mandating implicit bias training for the medical professionals they license. And since June 2022, Massachusetts physicians are required to take implicit bias training to get a new license or get recertified to practice.

Although researchers see this as a good step, they worry mandated training will become a one-off box-checking exercise. Sustained implicit bias training for physicians should instead be the norm, some emphasize. Hospitals also need to monitor and collect data on health care outcomes for different groups in order to monitor equity, Sabin says. “You have to know where the disparities lie and then begin to work backwards from that.”

As Jerry Coyne notes, implicit bias training and testing has been debunked as unscientific voodoo.

The article starts with a Black woman complaining that it was traumatic for a physician to say she was overweight, after she gained 100 pounds in a year. I am pretty sure that physician would say the same thing to a White patient.

Being a science article, it would cite data or studies to support claims of bias, if it could. There are studies showing different outcomes for Blacks and Whites, but with no control group to show a bias.

If you ever have to take one of these tests, I suggest first taking an online test to see what you are getting yourself into. These tests can easily label you falsely as a racist.