Friday, July 21, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Does weak gravity conjecture predict neutrino type, masses and cosmological constant?

String cosmologist Gary Shiu and his junior collaborator Yuta Hamada (Wisconsin) released a rather fascinating hep-th preprint today

Weak Gravity Conjecture, Multiple Point Principle and the Standard Model Landscape
They are combining some of the principles that are seemingly most abstract, most stringy, and use them in such a way that they seem to deduce an estimate for utterly observable quantities such as a realistic magnitude of neutrino masses, their being Dirac, and a sensible estimate for the cosmological constant, too.

What have they done?

In 2005, when I watched him happily, Cumrun Vafa coined the term swampland for the "lore" that was out there but wasn't clearly articulated before that. Namely the lore that even in the absence of the precise identified vacuum of string theory, string theory seems to make some general predictions and ban certain things that would be allowed in effective quantum field theories. According to Vafa, the landscape may be large but it is still just an infinitely tiny, precious fraction embedded in a much larger and less prestigious region, the swampland, the space of possible effective field theories which is full of mud, feces, and stinking putrefying corpses of critics of string theory such as Mr Šmoits. Vafa's paper is less colorful but be sure that this is what he meant. ;-)

The weak gravity conjecture – the hypothesis (justified by numerous very different and complementary pieces of evidence) that consistency of quantum gravity really demands gravity among elementary particles to be weaker than other forces – became the most well-known example of the swampland reasoning. But Cumrun and his followers have pointed out several other general predictions that may be made in string theory but not without it.

Boss of Californian community colleges wants to ban algebra

Several years ago, Penny asked Sheldon whether Leonard would get bored with her.

She lied to him that she was a community college graduate – in order not to be considered a stupid loser. Sheldon was surprised that she apparently thought that the opposite of a "stupid loser" was a "community college graduate". Well, Sheldon had very good reasons to be surprised. And the NPR gave us an additional reason two days ago (thanks to Willie):

Say Goodbye To X+Y: Should Community Colleges Abolish Algebra?
Kayla Lattimore talked to Eloy Ortiz Oakley, the chancellor of California's college community system.

Thursday, July 20, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Why we emphasize that the climate has always changed

Professional climate fearmonger Mr Stefan Rahmstorf finds the observation that "the climate has always changed" inconvenient which is why he wrote the text

The climate has always changed. What do you conclude?
He wants the readers of to dismiss the importance of the observation that the climate has always changed. In order to achieve this goal, he fights four straw men – he chooses four propositions that he believes not to follow from the proposition "the climate has always changed", even though at least some of them actually do follow, as I will discuss.

Too bad. If he had at least some integrity, he would study the actual reasons why people point out that the climate has always changed instead of his straw men – or I should perhaps say straw persons because he's a writer for a far left-wing activist website.

OK, why do many of us emphasize that the climate has always changed? It's because this important proposition of ours is primarily a response to statements such as
Climate is changing.
Climate change is real.
Haven't you heard these sentences? I have heard them thousands of times. You get a million of hits at Google even if you look for the precise form of these sentences.

We say that the climate has always changed in order to point out that those who say "climate is changing" or "climate change is real" don't have the slightest clue about this scientific discipline. The sentences such as "climate is changing" are formally true but they also implicitly say that
It is important information and a modern scientific discovery that climate is changing.
Or: A brand new process has started in the world we inhabit.
But these sentences are absolutely untrue because the climate has always changed. Everyone who says "climate is changing" and indicates that it is some important information that should affect our behavior if not policies influencing the whole national economies is a scientifically illiterate, probably brainwashed, layman or an intentionally deceptive demagogue or a liar.

The climate has always changed so the sentences such as "climate is changing" are as worthless tautologies as 2+2=4. It it silly to repeat such a statement and it is absolutely silly to suggest that such a sentence is a deep or original insight that may support one policy or another.

U.N.'s 17 sustainable goals by 2030: what the youth gets brainwashed with

Bill Nye, a former actor, is looking forward to the day when the older people will die out. The death of the older people is a necessary condition for progress in climate science, Bill Nye tells us.

Just try to appreciate how sick this individual is. In the real world, the progress in science doesn't require anyone's death. A scientist may do his research equally well if others – including the wrong ones, if they are wrong at all – stay alive. Nye's statement is just another example of the far left-wing Nazis' complete inability (or their lack of will) to distinguish science from political movements and from mass eradication programs. You can't be surprised that the wise commenters urge him to be the role model and be the first one who dies in order to end the farce that he calls his life.

We often complain that the Millennials are a lousy generation without ambitions, without spine, without courage, a brainwashed herd of cheap sheep. At the same moment, they're mostly just kids. They are victims. And they still have a chance to see the light. It's some of the old jerks like Nye who are actually responsible for having crippled the Generation Y.

Wednesday, July 19, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Was there a civilization on Mars thousands of years ago?

If you make it to the U.S. Congress, you have to do some work but there are lots of advantages. One of them is that you may finally ask the questions you were always afraid to ask – and you can ask them to the best paid experts in your country.

Well, Mr Dana Rohrabacher, a Republican from Southern California, has maximally used the opportunity.

He said that we should exploit the Moon as much as we can before we visit Mars. But concerning Mars, can I borrow these NASA folks for a minute? Now, wise guys, tell me: When you say that Mars was very different thousands of years ago, do you have the evidence that there was a civilization on Mars? Thanks for the good job you're doing.

When research has no beef, it's impossible to divide credit

A few days ago, would-be researcher Sabine Hossenfelder had a headache. Why? She saw an article in Nature that was written by Chiara Marletto and Vlatko Vedral and that speculated about some ways to test the phenomena involving both quantum interference and gravity. And Hossenfelder thinks that Marletto and Vedral should "cite" Hossenfelder because:

For about 15 years, I have worked on quantum gravity phenomenology, ... my research area has its own conference series ... I have never seen nor heard anything of Chiara Marletto and Vlatko Vedral ... If they think such meetings are a good idea, I recommend they attend them. There’s no shortage. ...
And so on. Later, Hossenfelder also notices that a "Bose-Eistein condensate" has appeared in one of the – not really plausible – experiments proposed by Marletto and Vedral. So some outsiders must be stealing her work, right?


The problem with Hossenfelder's claims is that regardless of those "15 years" and the bogus "conferences" for which she has misappropriated all the sponsors' money, her "field" doesn't really exist because no results that could be considered "beef of this field" have ever been found. All the texts that the likes of Hossenfelder pretend to be "research papers" are just worthless piles of junk whose only purpose is to fool the most gullible laymen and make them pay.

But she has made no impact on science (yet?). Marletto and Vedral don't mention people like Hossenfelder because people like Hossenfelder have never found a damn thing in physics.

Tuesday, July 18, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Lukin's 51-qubit Russian-American analog quantum computer

My former ex-colleague Mikhail Lukin has been doing some cool things in atomic physics and the most recent one is a 51-qubit quantum computer of a sort. Read the story

Russian, US Scientists Team Up to Create World's Most Advanced Quantum Computer
at the semi-official Russian Sputnik News server (or an original story in Russian or Google News).

You may see the different attitudes of the media in the two countries. While the U.S. media are obsessed with witch hunts against a son of Donald Trump who may have touched the hand of a Russian woman in the recent year, and they wouldn't dare to mention a Russian quantum computation advance at Harvard, Russian media are celebrating the cooperation of Russian and American scientists.

This Snap's hit from the 1990s, "Power", is started by a Russian announcement that the U.S. company Transceptor Technologies began to produce the computers Personal Sputnik. ;-)

Think twice who is the aßhole here. Yes, Lukin is Putin's agent according to a Democratic Party's lawmaker.

Their results were summarized in a fresh quant-ph preprint
Probing many-body dynamics on a 51-atom quantum simulator
The authors are mostly affiliated with Harvard's physics department, 1.5 of them with MIT, 1 with Caltech, and 0.5 of them with Harvard-Smithsonian. So despite Misha's ethnicity, that would probably make the paper an American one. But Lukin recently co-founded the Russian Quantum Center. I suppose that the plan is to do lots of things over there.

Monday, July 17, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Italy plans an act of war: 200,000 EU visas for free

According to the existing laws as well as common sense, Italy is one of the countries on the border of the EU visa realm – the Schengen Area – so it has the same duty as separate countries in most cases: It has the duty to make sure that no illegal immigrant gets to the space where he doesn't belong.

I think that the Italian prime minister and the most relevant minister should be abruptly tried in the court as soon as they fail to realize this duty and one or two illegal immigrants makes it through the EU border. Instead, they have allowed – well, they have really assisted – hundreds of thousands of illegal immigrants to get into the Schengen Area. During the weekend, we learned something incredible:

Italy plots 'nuclear option' to migrant crisis by giving EU visas to 200,000 incomers and sending them north as the country struggles with 'human warehouse'
They just want to give the visas valid for the whole EU to everyone who looks like an illegal immigrant! It's just stunning. Anyone in the world who wants to get to Europe may just sail to the Italian beaches and he automatically gets all the paperwork. Technically, they want to use the same system of temporary visas that was allowed in 2001, in the wake of conflicts in Yugoslavia. A difference is that there was a real war in Yugoslavia which was an adjacent country to several EU countries. And the drifting Yugoslavs of those times were mostly real refugees from a battlefront, not economic migrants. Libya sits at a different continent and except for Italy, we have had no historical links with that country. And almost all the people coming from Libya are economic migrants – and most of them aren't even Libyan.

Saturday, July 15, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Maryam Mirzakhani, RIP

This news is really tragic because the death is truly premature.

Maryam Mirzakhani, the world's first female Fields Medal winner and Persia's first winner of that award, died of breast cancer at an American hospital today. The disease was recurrent and things became terrible when the disease spread to the bone marrow.

She was born in 1977 to parents who always supported her even though they weren't ever too ambitious, she once told me. Her father Ahmad is an electrical engineer. Maryam is also survived by her Czech husband Jan Vondrák, a computer scientist at Stanford and their daughter Anahita (*2011). For a while, we were (theoretical physics!) classmates in Prague with him in late 1994 and/or early 1995 and he we overlapped at Rutgers (in different dpts) in 1999-2001.

Quantum teleportation is less magical than both Harry Potter apparating, Star Trek beaming

Popularizers of science often want the laymen feel excited. So they say "this experiment is amazing", "this experiment is magical". At the end, I think that this hype creates more damages than benefits.

Four months ago, we were being persuaded that the Chinese have constructed a quantum radar, something that can inform you about an airplane without any actual reflection of any radiation from the airplane. This is obviously impossible by locality, whether you use any quantum subtleties or not.

Right now, we're told about another wonderful achievement by the Chinese. They have succeeded in teleporting a particle to the outer space. It's basically the same topic – about the same Chinese and about the same transmission of quantum information to the outer space. There are stories everywhere. NPR chose the title

Beam Me Up, Scotty ... Sort Of. Chinese Scientists 'Teleport' Photon To Space
Brian Greene was asked whether the Chinese achievement is closer to Star Trek's "beaming" or Harry Potter wizards' "apparating". He answered that it's "somewhere in between" Harry Potter and Star Trek. He was mostly joking except that most readers and listeners won't understand in what sense he was joking – and many of them won't understand that he was joking at all. And it seems that this misinterpretation is really intentional.

Friday, July 14, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Harvard committee proposes to abolish the freedom of association

Last year, I discussed efforts by the extreme left-wing jihadists at Harvard to ban the single-sex clubs. "Are you now, or have you ever been a member of single-sex organizations?" students are gonna be asked starting from this year.

When first policies to harass Jews in Nazi Germany were established in Nazi Germany, the path towards gas chambers was straightforward and only took a few years. Harvard's trajectory towards eradication of some basic values of the Western civilization has been immensely speedy, too. Lots of things got much worse in the recent year. Two days ago, The Harvard Crimson told us that

Faculty Committee Recommends Social Groups Be 'Phased Out'
A 29-member committee led by the notorious jerk Rakesh Khurana and by musicologist Suzannah Clark has recommended that the College forbid students from joining all “fraternities, sororities, and similar organizations”—including co-ed groups—with the goal of phasing out the organizations entirely by May 2022. Wow. To be sure, they basically decided to ban all and any associations and clubs.

Classical simplex vs quantum ball

and another huge difference between classical and quantum physics

Bell's theorem is often hyped as a very important result about the foundations of quantum mechanics. There are two basic problems with this assertion: the theorem isn't a theorem about quantum mechanics at all; and it is not important. It is a theorem about local classical theories (those that were ruled out around 1925) and its claimed importance – the proven difference between classical and quantum theories – must be trivial to see for every intelligent schoolkid.

Here, I try to show you another elementary difference between classical and quantum physics that differs from the ideas in previous hundreds of blog posts.

For the sake of simplicity, consider one qubit, the simplest nontrivial quantum system, and let's describe it as the spin of an electron. And let's ask: What is the space of all possible mixed states? Those describe all possible states of the electron's spin that we may know before some observations. While pure states are of the form\[

\ket\psi = \alpha\ket{\uparrow}+\beta\ket{\downarrow},\quad \alpha,\beta\in\CC

\] the mixed states are \(2\times 2\) Hermitian matrices. All of them may be written as a combination of the unit matrix and three Pauli matrices:\[

\rho = \frac 12 \zav{ 1+\vec n \cdot \vec \sigma }

\] The coefficient of the unit matrix had to be \(1/2\) for the trace of \(\rho\), the total probability, to be equal to one. Hermiticity guarantees that \(\vec n\) is a real 3-dimensional vector. Also, the density matrix cannot have negative eigenvalues which tells us that\[

|\vec n| \leq 1.

\] This inequality is saturated if and only if the qubit is in a pure state i.e. if \(\exists \ket\psi:\,\,\rho =\ket\psi\bra\psi\). Excellent. So the density matrix is parameterized by a vector with \(|\vec n|\leq 1\), i.e. by a three-dimensional ball!

Thursday, July 13, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Celebrating Russian pop-music

Donald Trump's son Donald is being harassed for having met an attractive Russian female lawyer. I am amazed by this hysteria and find it as wild and overblown as Russia's FM Lavrov. What's wrong about meeting a Russian lawyer, especially if she could have possessed some useful data on the opponent of the campaign that you direct? Is a Russian lawyer worse than a Japanese, Spanish, or Mexican one? These efforts to outlaw the very meetings with people who are Russian are exactly on par with the Nazis' anti-Semitism and if you think that you're any better, Yankees, you have just blinded yourself. This criminalization of meetings with the Russians corresponds to the situation of the Jews in Germany around 1937.

While Czechia belongs to the Western civilization and has been culturally closer to Germany than to Russia for some 1,000 years, it's just impossible for me not to understand this Russophobia personally because of our Slavic roots – and because of the fact that most Americans are so immensely ignorant about the European geography and history that they don't even understand that e.g. Czechoslovakia has always been an independent country, from the USSR, where people spoke their language and didn't follow the Russian culture most of the time, among other things.

Today, Czech media informed us that Tamara Miansarova died of pneumonia complications at the age of 86. She was the original singer of "Пусть всегда будет солнце" ("Let There Be Sunshine") in the 1960s. This song was obviously a part of the propaganda in the communist bloc and that's why we were served it but I still find this song extremely touching, excellent musically, and to say the least, it is the best song promoting peace that I know.

Wednesday, July 12, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

SI units: \(h,k_B,e,N_A\) will be set to known constants

Between 13th and 16th of November, 2018, the 26th meeting of The General Conference on Weights and Measures will convene in Versailles, France. The Symmetry Magazine tells us that it is expected to cause a revolution in the definition of SI units.

In 2012, I became somewhat loud while screaming "let us fix the value of Planck's constant" although I was recommending it more silently for decades. Last year, my goal finally got closer while plans to redefine one ampere were already around, too.

Hysteria over double standards in food products

The media in much of post-communist Europe are obsessed with a fashionable topic – the observed double standards in food products. Transnational companies sell their products – in identical packages – in many countries but the composition is sometimes different. See e.g. this Reuters story about the panic in Bulgaria or another one about Czechia (or a test reported in Radio Prague EN).

We're often calling ourselves the "dumping ground of Europe" and stuff like that. I believe that all this anxiety is painful. What makes us different is that some of us – and our politicians – still expect the governments and even the EU to dictate what citizens should eat and what food producers should offer them.

Tuesday, July 11, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

The uninhabitable galaxy

Guest blog by Peter Deutsch-Doveking, the director of the International Bureau for the Galaxy Salvation from a Cow Fart (IBGSCF)

In the July 10th issue of the NY Magazine, David Wallace-Wells talks about the looming uninhabitable Earth. The climate Armageddon will much worse than any person in the world can even imagine. He points out that the people who imagine the cities like Boston and New York to be flooded by the rising seas after the Antarctica melts are basically just deniers. These people are just touching the surface because the actual horrors will be much worse.

He divides some of the problems to sections titled I. Doomsday, II. Heat Death, III. The End of Food, IV. Climate Plagues, V. Unbreathable Air, VI. Perpetual War, VII. Permanent Economic Collapse, VIII. Poisoned Oceans. There are hardcore deniers such as those at who seem to reject even these self-evident catastrophes – even though 99.9997% of the world's climate scientists say that they are real – but the actual truth is that even David Wallace-Wells' views only touch the surface because we're facing much worse events.

Monday, July 10, 2017 ... Français/Deutsch/Español/Česky/Japanese/Related posts from blogosphere

Physics of sailing

For the first time in my life, I could try what it means to pilot a yacht. My friend, the captain, took us to the Lake Lipno, the largest Czech-or-Slovak, 5000-hectare reservoir with a hydroelectric power plant built near the spring of the Moldau River in Southern Bohemia, miles from the Austrian border.

Bedřich Smetana, the Moldau. A decade ago, I tried to exploit the knowledge of which parts of our national river were described in various segments of Smetana's composition. Lipno is seen e.g. at 1:50, 1:58, 2:01. Smetana had predicted the big dams in the second part of the composition.

Our captain did almost everything for us – and he worked in his pub just minutes before our 21-hour-long sailing, as well as minutes after that. But I could at least enjoy to be the acting captain at night when I skipped sleeping. Unfortunately, our Yamaha motor stopped working minutes after we began our adventures. That got combined with another problem – there were many windless hours. You can imagine what it feels like to sit in the middle of the Bohemian Sea and be unable to do anything about it. The last 2 miles were impossible, too: We asked another yacht to bring us to the port which they kindly did.

It's fun to experience some practical physics. I have always found sailing counterintuitive. The practical experience has erased my doubts that it's possible, however. ;-)