December 3rd: ITU, U.N. could end the free Internet

Lots of worried voices have claimed that various large corporations such as Microsoft, Google, or others would restrict the freedom of the exchange of information on the Internet.

I have always considered these worries silly – and I will always count the people with a hardwired corporation-phobia to be hardcore communists. In particular, none of the IT or communication corporations has ever had a sufficient monopoly to stop the flow of the information – and most of the largest ones are literally motivated to support as diverse ways of exchanging the information as possible because their profit really boils down to these processes.

The free market works, stupid.



But here is a similar threat I find much more credible. Between December 3rd and December 14th, there will be a conference of the ITU, the 1865 International Telegraph Union (that changed the middle word to "Telecommunication" to create the illusion that its core has been modernized but it has not) which became a U.N. agency, in Dubai.



A majority vote behind the closed door may bring a radical power grab which could seriously cripple the freedom of the online exchange of information.




You may sign a Google Petition against the possible ITU power grab.

It may look like the civilized countries generally oppose the undesirable developments. For example, The European Parliament voted in advance to block an ITU power grab. But those things won't be decided by the European lawmakers.

The idea of a majority U.N.-style vote about important questions such as the freedom on the Internet looks somewhat worrisome to me. It's very easy to imagine that the anti-freedom-on-the-Internet countries represent a majority in the United Nations. Start with the obvious hardcore villains such as China and Iran and add softer governments of a remotely similar kind such as Russia. You may surround them with pretty much all the countries in the Muslim world, almost the whole remainder of Africa, some of their allies in Latin America, and so on. I think you will easily find out that the villains enjoy a majority in the U.N.



Now, when those folks get a majority U.N. support for such a similar plan, will the Western world's governments be sufficiently assertive to reject all truly sick policies (government approval of websites, custom duty or tariffs, and so on) that the coalition around China, Iran, and Russia could prefer? Will they really clearly say that they're ready to wage a nuclear war against the villains to protect the freedom on the most important information infrastructure of the early 21st century? They definitely should. But there are so many people who are hysterically afraid of a nuclear war that they could just prefer to say OK to the Chinese and Iranian comrades.

These mysterious villains behind the closed doors – and not the corporations skillfully controlled by the almost always beneficial invisible hand of the free markets – is what your humble correspondent is kind of afraid of.

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The 234-bit gene that turns an ape into a man

You must have wondered why some of us are human while others are just apes. As I learned from an article that was sent to me by Peter F., all the difference may boil down to 117 base pairs on the 20th chromosome.

Study: Single Gene, Plus Some "Junk" DNA Turned Ape Ancestors Into Modern Man (Daily Tech)

Recall that all the information needed to create and run an organism is digitally stored in the DNA molecule, a sequence of base pairs. Each base pair is either AT or TA or CG or GC (the first and second letter correspond to the 1st strand and the 2nd strand of the double helix and they're locally distinguishable). Because you have 4 possibilities, the base pair carries roughly 2 bits of information.



The DNA sequence is divided into chromosomes. Humans have 23 pairs of chromosomes; all apes have 24 pairs of chromosomes. In total, they carry a few gigabytes of genetic information (3.08 billion base pairs or 6.16 billion bits), not far from an operating system. It's somewhat hard to believe that our not having one of the chromosomes is what makes us – apparently and only in some cases – superior relatively to the apes. There has to be a "positive difference" that favors us, too.




The researchers have previously looked for active genes – shorter sequences of base pairs that play some role (not just junk DNA) – and they have found essentially one solution: the MIR 941-1 gene (it also produces equally named MicroRNA molecules in all our, eukaryotic cells). The authors of the article in Nature Communications

Evolution of the human-specific microRNA miR-941 (Hai Yang Hu and 12 co-authors)

have used some now common methods to determine when and where this inherently human gene appeared for the first time. They found out it appeared between 6 million and 1 million years before Christ (or the present, for that matter: note that because of this parenthesis, this blog entry will become outdated in as little as one million years).

It's fun to repost the whole abstract. I hope that some other readers will, just like your humble correspondent, misunderstand some of this genetic jargon (and its content):

MicroRNA-mediated gene regulation is important in many physiological processes. Here we explore the roles of a microRNA, miR-941, in human evolution. We find that miR-941 emerged de novo in the human lineage, between six and one million years ago, from an evolutionarily volatile tandem repeat sequence. Its copy-number remains polymorphic in humans and shows a trend for decreasing copy-number with migration out of Africa. Emergence of miR-941 was accompanied by accelerated loss of miR-941-binding sites, presumably to escape regulation. We further show that miR-941 is highly expressed in pluripotent cells, repressed upon differentiation and preferentially targets genes in hedgehog- and insulin-signalling pathways, thus suggesting roles in cellular differentiation. Human-specific effects of miR-941 regulation are detectable in the brain and affect genes involved in neurotransmitter signalling. Taken together, these results implicate miR-941 in human evolution, and provide an example of rapid regulatory evolution in the human linage.

To be brief, our monkey ancestors became human when they escaped regulation and Africa. The individuals who want to return regulation to the human society want to revert the progress and make us apes again.



Ms Tereza Fajksová won the global Miss Earth 2012 (Biomiss 2012) contest promoting environmental awareness. The young woman, shown with some biomakeup, has been the hero of the local Filipinos for months, despite the fact that their local Miss Earth Philippines said that she wanted energy to be renewable while the winner's "positive" attitude to Nature means mainly that she loves fishing and mushroom hunting. ;-)

Fine, so it's probably a crucial gene that made the first humans – skillful apes.

It's irresistible to look at the servers of the University of California in Santa Cruz where the human genome and other genomes is mapped:

Gene turning apes to humans (UCSC)

These 117 base pairs (it's not an accident that the number is a multiple of three!) are those that are most responsible for ours feeling more skillful or, in many cases such as mine, at least cleverer than apes. In our way of measuring the information, it's just 234 bits.

In many respects, the digital information stored in the DNA and the digital information defining software is comparable, even when it comes to the size and its dependence on the abilities of the program or the organism. But these 117 base pairs are 234 bits or 29.25 bytes of information only. And they can make a human out of an ape? It's remarkable, isn't it?

It's like taking your code for MS-DOS and adding the following 29 bytes somewhere to the MS-DOS executables:

Behave like a userfriendly OS

I really wanted to write "Behave like a user-friendly OS and add all those nice windows, you chimp-like primitive operating system!" but I didn't have enough memory for that.

And this extra command would turn the MS-DOS into Windows. Isn't it cool? This represents anecdotal evidence that the abilities of an organism aren't simply monotonically increasing functions of the DNA size – even though we tend to think that it's pretty much the case for software. Instead, the "need for longer DNA codes" is just an approximate, overall condition, and sometimes very modest changes (MIR-941) and/or subtractions (missing 24th chromosome) can make a huge positive difference, too.

Nature stores the information in a much less predictable, more noisy way. This "holographic" feature of the DNA code is what makes it both impenetrable for a human reader as well as natural. On the other hand, the impact of pieces of software is much easier to be reconstructed which is why software is less subtle and man-made. Nature doesn't care about transparency and comprehensibility which is why it may afford obscure DNA codes whose importance isn't immediately clear for the DNA code's readers (She always understands Herself, She knows what to do, and She doesn't have to care for others).

To be more specific and geneticist-like, the birth of a new MicroRNA modifies the expression of hundreds of other genes – and the small code change therefore has a big, nonlocal effect.

Needless to say, genetics isn't the ultimate reason why I write these comments. I am secretly talking about physical theories. Deep, natural, physical theories often have very important consequences but one must learn and think hard to figure out what these consequences are. If someone isn't patient or smart enough and/or complains that the consequences aren't immediately obvious, he is implicitly demanding Nature to be overly simplistic, man-made, and user-friendly. But Nature isn't obliged to be like that and the person who complains is de facto an ape.

And that's the memo.

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Lost City Raiders, a B movie

My newly favorite Czech TV channel, Prima Cool (which airs not only The Big Bang Theory), was broadcasting a silly 2008 U.S.-German-Austrian science-fiction catastrophic global warming film, Lost City Raiders, tonight.

If you have 98 minutes, the whole movie is right here on this blog.



I kind of enjoy watching catastrophic movies – and view it as 1% of my job, too. In this case, I feel satisfied and you should also feel satisfied because this cheap $6 million movie scored the worst grades you may think of, see e.g. 39% at IMDb.

The rest of the blog entry is full of spoilers.




It's year 2048, a power of two, and the sea level has increased by something like 15 meters (the reality will be less than 0.1 meters) which, the authors believe, puts about 1/2 of North America (mostly the Eastern 50%) under water (in reality, even 15 meters would only submerge a tiny percentage of the land).

So they realize that the IPCC was right – in fact, the catastrophic global warming was worse than previously thought, even when they said that it was worse than previously thought – and a clever cardinal from the New Vatican (which is the ordinary Vatican with some buildings replaced by floating islands above the former city) figures out how to save the Earth. They must find the staff of Moses in the flooded streets of the New York City that became a part of the ocean. A man, a scuba diver who later dies – but has two (adopted) sons – accepts the challenge and the sons ultimately complete the task (despite explosives and puzzles in the churches) and meet with their tough babes in a restaurant in order to emit a few "wise" words about the future.

You may think that the effects are cheap and unspectacular but it's probably nothing compared to the predictable and stupid plot. The movie was addressed to the most undemanding audiences and once again, we must feel some kind of a satisfaction when we see that a politically correct theme and attitudes aren't enough for success. Thank God – even though in some cases, it does look like these conditions are sufficient for success.

When I said all these critical words, I must say that I have enjoyed the movie as entertainment. My rating is 60%.

---

P.S.: Some details. Moses' scepter is originally supposed to be in a Vatican library. It's not there: a member of the Order of the Temple stole it 800 years ago. So it could be in his grave in Dresden, DDR. They go there but find out that they have a competition: the former girlfriend of one of the sons, Giovanna. She's a scuba diver and self-taught geologist who tries to lower the global sea level by whole millimeters by detonating small holes in the ponds. ;-)

She's hired by an even more hopeless crackpot, the greatest owner of the land in the world, who wants to slow down the sea level rise, too. He has two methods: to hire Giovanna as a researcher who creates holes in the Mediterranean Sea so that the ocean pours into these holes (it sounds similar to some policies proposed by the IPCC); and to hire her to find the scepter, too. Well, a competition for the father and two sons. The rich guy who hired Giovanna has a spy in the Vatican, another cardinal. In Dresden, the graves have double floors etc. The father dies there after an explosion when a rock falls upon him.

After his death, the sons bring some historical object from the grave to the "good cardinal": the father asked them to do so. However, they want to abandon the risky job of looking for the scepter. That changes when the good cardinal tells them that the good cardinal, their adoptive dad, as well as their (late) biological fathers (archaeologists) were members of a special cult looking for the scepter.

Meanwhile, it also turns out that the rich guy, Niklas, has sold his land. He actually wants to raise the sea levels and then turn it back when he cheaply buys the land beneath the sea level, and so on. He wants to destroy almost everything and control the world. His cardinal-spy is caught at some time and his motivation was even worse: he wanted to complete the end of the world, a job that God began 2 millenniums earlier. ;-)

The sons who have decided to continue in their three fathers' mission hire a busty waitress-mechanic, Carol, who gets a new coil for their boat, avoids a fat innkeeper who wants sex with her because an old placard for his pub only covers 1/2 of the value of the old stolen coil (she abruptly becomes a sweetheart of the other brother who didn't have sex with Giovanna), and they go to see the grave of Richard the Lionheart – it may be at 3 places. Giovanna and the rich guy are there before them and find the scepter. Giovanna becomes sure that the rich guy is a villain a minute before he closes her body to the grave together with Richard the Lionheart so that some archaeologists may find the bones of Richard and Giovanna in the year 3048.

When the grave with Giovanna and Richard is thrown to the ocean, it just happens that her former boyfriend is swimming around. He opens the box, saves the babe, and they easily overtake the boat of the richest guy in the world. ;-) Once they're in charge of the scepter, they notice that it works as a perfect projector. It shows a movie about Pangaea and some "electromagnetic intersections" around the Earth. By a complete coincidence, Giovanna who watches is is the only person in the world who understands these electromagnetic intersections. So their skepticism goes away. (Giovanna starts to tell everyone that science is constantly failing because they used to be 9 planets and now there are just 8 planets – surely a hot topic in the year 2048; her anti-science interpretation of the redefinition of a "planet" remains unchallenged).

They sail to one of the intersections and find out a cave. The scepter is also a key to a lock which opens a sophisticated lab. Inside the lab, there is a convenient 13,000-kilometer-deep (about 3 meters in diameter) hole through the Earth, too. :-) The plans on the walls prove that the mechanism is nothing else than what Giovanna has been working on (but a greater realization of it) – a plan to lower the sea level. The door closes, confines them, and for some time, they're afraid they would die while they could save the land. But 3 of the 4 young people escape when the door temporarily opens.

The last guy has to return to the lab in the cave when he finds out that the evil cardinal – who escaped from the New Vatican after he was outed by the good cardinal as a spy (he instantly jumped to the New Vatican waters) – tries to stop the process of the saving of the Earth. They fight for a while. Finally, the son manages to throw the cardinal to the 13,000-kilometer-deep hole and save the scepter. He restores the process and thinks that he will die. But fortunately, he saves his life, too.

The process is activated after a while. A huge hole is created in the Earth and a big fraction of the world ocean pours there – some kind of giant waterfalls. Well, as the two couples are drinking champagne in the restaurant, they're told by the good cardinal on the screen of a 2008-style cell phone that the sea level dropped by 10 meters in the Mediterranean Sea. They don't want to be annoyed by such details when they are having fun. The cardinal tells them that the sea level in other parts of the world ocean isn't dropping but it seems that they will have some extra job, to go to a few dozens of other similar spots where they have to produce a similar huge hole into the Earth to stop the flood.

All the previous activities done for the cardinal and the scepter cult were unfunded. So I suppose that the rest of the activity needed to save the Earth didn't receive a eurocent of the EU taxpayers' or New Vatican money, either. Obviously, they saved the world in a cheaper way than the UNFCCC and the Kyoto protocol.

As I have said, I developed the pleasure of watching and enjoying movies even if every second of them is completely illogical nonsense, so I liked the film despite – and perhaps partly because – of its immense stupidity and lack of realism. Realistic if not mundane yet fictitious movies and novels is something I can't stand; it's the socialist realism that I am immensely bored by (independently of the politics).

---

Movie: 2012

One day later, on Sunday, I watched another catastrophic movie called 2012 and shot in 2009. Its budget was $200 million, about 30 times more expensive than the Lost City Raiders, but it was more chaotic and even more silly from a scientific viewpoint.



Full movie

The Mayan prophecy about December 21st, 2012 gets realized in a bizarre way. The Earth's core gets quickly hot and the surface is cracking, and so on. The reason behind all these phenomena? The neutrinos from the Sun "mutated" and became equivalent to microwaves. Holy crap. Didn't they also wanted to say that neutrinos started to have sex with bunnies? ;-)

Alternatively, couldn't they have just asked a physics grad student to invent something slightly less dumb if they already pay $200 million for the movie so that all the movie staff wouldn't be identified as a gang of uneducated naive imbeciles on physics blogs?

With this being said, it was clear that the effects were much more professional and expensive than in the Lost City Raiders – and I was crying like a small baby.

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Climate propaganda in Australia

Joanne Nova (see also Anthony Watts) made sure that my pressure didn't stay relatively low for too much time in the morning. Why? I have listened to a 16-minute long show on the ABC, the Australian public radio, called

Attitudes to climate change (audio)

We used to hear some remotely similar propaganda programs until 1989 – although not too many have been this hardcore in the 1980s, I would say (in particular, I don't remember a single radio program against Havel or dissidents etc. that would be this nasty) – but the public radio and TV simply can't produce programs that would be this dishonest, manipulative, hateful, and insulting anymore. It's surely a part of the reasons why I think that my homeland is already well ahead of countries such as Australia when it comes to democracy.




At the beginning, the host Robyn Williams says that the "denial" of climate change is on par with paedophilia, promotion of asbestos, and drug trafficking. Nice. But to be sure that this wasn't a random excess, the following 16 minutes are dedicated to aggressive and virtually unchallenged delusions by a hardcore Marxist called Stephan Lewandowsky who is insulting and trying to bully all people who have at least elementary understanding of the atmospheric physics; and all people who realize that the free market is important for the health of the modern economy.

Right-wing and pro-market people are generally labeled as those who deny the HIV-AIDS link (I surely don't), the smoking-cancer correlation (I surely don't), and so on, and so on, while leftwingers are praised as being generally supportive of science and understanding science (most of them don't have a clue and the most – but not all – anti-scientific, Luddite attitudes come from the Left these days). A few minutes are spent by attacks against the energy industry and other important things that may be found on the black list written by the hardcore postmodern left-wing activists.

In my country, immoral, hateful, low-quality humans similar to Mr Stephan Lewandowsky probably wouldn't be invited to a public radio or TV because they have nothing interesting, useful, or true to say. And they don't have any comparative advantage or rare knowledge to offer. Such people have the freedom to express their "opinions", if the disgusting stream of lies and insults may be called "opinions" at all, but they are doing so in the discussion forums below articles on the Internet (where they're being removed by moderators once they cross various thresholds), not on public radio stations listened to by hundreds of thousands of people.

I encourage all the Australian readers to be deeply ashamed of their inability to fix their national public radio station and to eliminate hardcore totalitarian liars from institutions that are supposed to provide all the taxpayers with impartial information. I don't have the time to go through every statement that these "people" have made and I think it's not right to waste much time with marginal figures such as Mr Stephan Lewandowsky and the host but yes, virtually every sentence said on that program was a malicious lie.

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Clashes over EU budget

Leaders of the EU countries met in Brussels and they are trying to agree about the 2014-2020 EU budget – about a trillion of dollars. And as the Washington Post and almost everyone else notices, it ain't pretty. France clashes with Britain and smaller countries play their own small games, suggesting possible vetoes.



Click for the Guardian infographics on EU finances...

One could say that it's possible to define "overall fair rules" how to redistribute the resources. However, there's still a subtle question: How large is the overall budget? Now, the countries that are net payers obviously want the overall budget to shrink; David Cameron is a clear advocate of that. Countries that have been overall recipients, including Czechia, want to stay recipients and they typically want the budget for solidarity ("cohesion spending") to grow.

(Except for Prague, all regions of Czechia are counted as poorer regions that should be receiving this kind of aid. Czechia is a net recipient but on a per-capita basis, we're the smallest recipients among the post-socialist EU member states. Among the net recipients, we're the per-capita smallest ones after Cyprus, Spain, Ireland, and Belgium.)




It isn't easy to agree about all these numbers if 27 leaders have to do so. In fact, I find it somewhat remarkable that such clashes haven't occurred so far. Decades have been free of this obvious "egotist" behavior of the individual countries. But the idea about people and nations ready to pay anything to their fellowmen is a communist utopia so the clashes sooner or later had to start. They had to start as soon as some politicians devoured the forbidden apple and realized that they have previously acted in a stupid way.

Why don't these clashes occur in large unified countries, e.g. in the U.S.? Well, that's easy. These countries have a federal government that decides about all the member states of the union by majority or similar votes. So if your viewpoint on some part of the federal budget or redistribution seems to be in a minority, the federal elections are pretty much the last moment when you may try to change something about your political weakness.

But the leaders who are deciding about these EU budget rules aren't elected by the Europeans. As a group, they can't boast any political capital they have received from the voters in the whole union. They are only representing the individual nations – at most. So it's obvious that sooner or later, these politicians have to protect the interests of the single nation that elevated them in politics. When the clashes become strong enough, a failed unified country of course converges towards the annihilation of the shared budget. When no country pays anything to the "common cause", it's the ultimate fair arrangement that everyone has to agree with (although the former recipients may be upset, they can't do anything about it).

While leaders such as Merkel, Hollande, Cameron, and Nečas weren't elected by all the EU voters, the EU has some bodies that were elected in "European elections". I am talking about the European Parliament. But it's still true that each nation only elects its own fraction of the Parliament (it's the case in the U.S. Congress as well but when two continents are doing the same thing, it's not the same thing). It doesn't affect the composition of the representatives from the remaining countries. This makes a difference.

Even more seriously, the EU doesn't really have "its own money". It is receiving the money from the individual nations. That's why it's really irrelevant what the EU lawmakers think about the overall size of the EU budget. If they don't get the money from the national governments, they have nothing to redistribute so their opinions are only good enough to be written on urinals in Strasbourg.

This is of course a tough situation that may evolve in both ways. If the desire of the nations to think as a "single nation" prevails, they agree about things and create a framework in which the EU institutions don't have to "beg" for every eurocent all the time. If the EU were really converging towards a federation, and I hope and think it's not the case, the national taxes could even be supplemented or replaced by the EU-wide taxes which would clearly give the central EU bodies much more power. Such a new tax could be administered or modified by the European Parliament. However, the individual nations would first have to allow the EU to collect the money on their territories, according to its own rules, and order its law enforcement forces to enforce the EU-Parliament-sponsored laws, too. Just to be sure, those would be huge changes even if the EU tax rate would start at 1% or 2%. On the other hand, if the nations realize that their main identity is the national identity, and I think it's the case, the shared EU budget will be increasingly viewed as a controversial, artificial, obsolete construct and when these controversies are resolved, the decrease of this budget is the direction we should expect.



In Czechia, Beethoven's EU anthem has been rebranded as a celebratory "Song for Bára" (Špotáková, a top javelin thrower). They sing that their parents are crying when Bára wins and when they grow up, they will be like Bára, terrors of all the measurers. They're just not sure where they will look for their firefighters (Bára's partner is one of them).

It seems to me that it will become increasingly fashionable and natural among the top EU national politicians to protect the narrow national interest of their countries. The EU countries should realize that they're mostly a group of 27 spouses who no longer sleep with each other and they should attempt to go through a velvet divorce. It would be silly to overreact. Just because the prime ministers don't agree about the EU budget – usually for obvious reasons – doesn't mean that they're obliged to wage a war against the remaining EU countries. There are lots of things in the EU that don't cost almost anything, various multinational agreements that are good for everyone. And even when emotions run high and the EU converges towards some kind of a partial dissolution, they shouldn't forget that there are many things – not only the free trade but especially the free trade – that almost no one really wants to abandon simply because it works. It works without any propaganda. Those things that don't work and that are likely to lead to increasingly bitter arguments should be gradually abandoned.

Make no doubts about it: We in Czechia know what we're talking about here. Slovakia used to be a net recipient in the Czechoslovak budget. When this "Czech duty to pay" was supplemented by assorted coherent and incoherent memes about improved Slovak autonomy and independence in various ways, sensible Czech politicians – even though they had promoted federation for years – realized that these arguments became a waste of time and a complete dissolution of dissolution was the zeroth approximation to the most streamlined new arrangement we could think of. The Hyphen War (called "the Dash War" in Czechia: there was a meta-war about how the Dash War should be even called haha) about the presence or absence of a hyphen in Czecho(-)Slovakia became an early sign for many Czechs that we should just stop this hassle.

When I say these comments, it doesn't mean that I don't understand the Czech prime minister who is trying to get as much money as possible. Of course that I understand him. To collect more money from Brussels means that he will be viewed as a more successful Czech politician who has helped his country. At the same moment, I think that countries that want to remain "overall recipients" aren't really those that should have the last word. In the Czech case, we are talking about 2% of our GDP that is being added from the EU every year (or every arbitrary unit of time): our consumption plus investments are artificially increased by the factor of 1.02 by our EU membership. It's not a dramatic transformation of our finances we couldn't live without; at the same moment, it's comparable to our budget deficit so it is not quite a negligible amount of money.

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SUSY exists because the number 3/2 can't be missing

Paul Frampton: Off-topic sad news: he gets 4.67 years in prison for drug smuggling; Google News. He may be moved to the U.S. in 2014 if he applies. They found a note, "1grm/200U$S. 2000grms/400000 U$S", handwritten by Frampton himself on which he calculated the price of the stuff. He admitted he wrote it but only after the stuff was found, weighed, and he was accused. So the curious Paul calculated what he was supposed to earn, too. When cops accuse you of anything in Argentina, shut up and don't calculate anything! Even more seriously, however, Paul's e-mail to (fake) Ms Denisa Krajíčková a day before he was caught allegedly "worried about sniffer dogs looking after the small suitcase".

This blog entry elaborates upon a simple point made by Nima Arkani-Hamed in a recent talk (and by others). First, look at this IQ test. What is missing in the box?\[

\begin{array}{|c|c|c|c|c|c|}
\hline
j& 0 & 1/2 & 1 & ??? & 2\\
\hline
\end{array}

\] Those of you who have figured out that \(???=3/2\) earned a ticket and they may continue to read. ;-)




The numbers in the table are the spins of the known elementary particles. The Higgs boson became the first discovered spinless elementary particle, one with \(j=0\). Leptons and quarks have \(j=1/2\). The photon, gluon, W-boson, Z-boson – gauge bosons – carry \(j=1\). And a \(j=2\) graviton has to exist because we know that there exist gravitational waves (see e.g. 1993 Physics Nobel Prize) and because all energy at the frequency \(\omega\) is inevitably packaged into quanta of energy \(E=\hbar\omega\), because of the most universal laws of quantum mechanics. Why? If all expectation values etc. \[

\bra\psi L \ket\psi

\] are demanded to be periodic with period \(2\pi / \omega\), it follows that \(\ket\psi\) must be periodic with this period, up to an overall phase. But if \(\ket\psi\) is a linear superposition of various energy eigenstate terms whose time dependence is \(\exp(Et/ i\hbar)\), it follows that between \(t=0\) and \(t=2\pi/\omega\), the relative phases must return to the original value which means that \(E_i-E_j=N\hbar\omega\) for any pair of allowed eigenvalues \(E_i,E_j\). If the two states included in the superposition differ by an addition of a particle or particles, the particle(s) must have \(E=N\hbar\omega\) for \(N\in\ZZ\).

Again, if you don't understand the argument above sufficiently clearly so that you have eradicated all doubts about the existence of gravitons, I kindly ask you to stop reading because you're not qualified to study or discuss the allowed spins of elementary particles.

Why gauge symmetries are needed

Now, when we have hopefully gotten rid of 99.9% of would-be readers :-), we may continue with gauge symmetries. This topic has been mentioned many times on this blog but let's make the point once again. If you deal with fields that manifestly obey the Lorentz symmetry and whose spin is \(j\geq 1\), you critically need a gauge symmetry, otherwise the probabilities would have both signs. But you don't want the probability of your winning in a lottery to be negative. It's worse than just to lose the money: you would be a ghost, a bad ghost, if your probabilities were negative. And that's worse than to be a zombie, believe me.

It's not too hard to see why a gauge symmetry is required. Take a creation operator for a particle, \(a^\dagger(k)\), and produce a one-particle state out of the vacuum \(\ket 0\):\[

a^\dagger \ket 0

\] That's nice. We want this state to have a positive (or at least non-negative) squared norm because this squared norm gives you the probability of the projection operator \(1\), the truth, and it should be 100 percent. For one creation operator, the equality between the norms\[

\braket{0}{0} = \bra 0 a(k)\cdot a^\dagger(k) \ket 0

\] is guaranteed by the commutator below and by the annihilation skill of the annihilation operator:\[

[a(k),a^\dagger(k)]=1,\quad a(k)\ket 0 = 0.

\] Of course, the usual normalization of the creation and annihilation operators involves a \(\delta\)-function but I don't want to go into messy details. Now, the description here is OK for scalars but what happens when the creation operator has some extra indices related to the spacetime?

Start with the \(j=1/2\) Dirac spinors. The fields have an extra index \(i=1,2,3,4\) and the relevant commutator – well, we need an anticommutator for fermions but it changes nothing about our discussion – is\[

\{ c_i(k),c^\dagger_j(k) \} = \delta_{ij}

\] The Kronecker delta is actually right but you could make an error – one that would prove that you know something but you don't know it quite well – and write \(\gamma_0\) instead of the identity matrix. It's because \(\psi\) and the Dirac conjugate \(\bar\psi\) rather than the Hermitian conjugate \(\psi^\dagger=\bar\psi\gamma^0\) are naturally conjugate to produce Kronecker deltas. For example, \(\bar\psi\psi\) and not \(\psi^\dagger\psi\) is Lorentz-invariant. However, the equal-time commutator has another time index in the game (the time-like vector enters because it's orthogonal to the slice on which we define the equal-time [anti]commutators), one which translates to \(\gamma^0\), so the two factors of \(\gamma^0\) cancel and you actually do get the Kronecker delta on the right hand side.

Now, notice that we're kind of lucky that the right hand side is a positively definite matrix \(\delta_{ij}\) rather than an indefinite matrix such as \(\gamma^0_{ij}\) we have mentioned. When you create particles with \(c^\dagger_i\), they will still have a positive norm. In fact, even when the role of \(c\) and \(c^\dagger\) is interchanged for one-half of the values of the index \(i\), because you have to fill the Dirac sea and introduce antiparticles as the holes in the Dirac sea, you will still create positive-norm states because the relevant positive definite construct above was the anticommutator which was symmetric. It just didn't care which of the factors was \(c\) and which of them was \(c^\dagger\).

The percentage of readers who have given up has jumped from 99.9% to 99.99%. The remaining reader, if any, knows this stuff anyway and she or more likely he may notice that we have just seen that \(j=1/2\) fermionic operators produce nicely positive definite particle states.

But what about \(j=1\)?

The creation and annihilation operators have to carry an extra vector index \(\mu=0,1,2,3\). The commutators or, equivalently, the normalization of one-particle states is\[

\bra 0 a_{\mu}(k)\cdot a_{\nu}^\dagger(k) \ket 0 = C\cdot g_{\mu\nu}.

\] The right hand side has to be proportional to the metric tensor, otherwise the formula would violate the Lorentz symmetry! But the metric tensor has both positive and negative eigenvalues. So some of the states are positive definite while others are negative definite.

The latter states would be a problem because they would lead to negative probabilities once again. (Well, it's actually the first time in our story when they're a genuine threat.) In fact, it is such a big problem that we don't want too much of this problem. It means that the overall sign must be such that the 3 spatial polarizations are positive definite and only the remaining 1 time-like polarization has a negative squared norm. What do we do with it?

It's simple. We must kill it. But we're physicists, not murderers or terrorists, so we must kill it in an elegant way. An elegant way to kill states (yes, Gazan terrorists, we are able to kill whole states!) is to make them unphysical. A reason allowing us to delegitimize a state and declare this state unphysical is that this state isn't invariant under a gauge symmetry.

For each value of \(k^\alpha\), we need to kill exactly one polarization. So we must have enough generators of symmetries, one per each \(k^\alpha\) or, equivalently, one per \(x^\beta\). Clearly, we need a gauge symmetry. We must have a generator \(j^0(x,y,z)\) for each point in the three-dimensional space and we require all the physical states to obey\[

j^0(x,y,z)\ket\psi = 0.

\] Also, states of the form \(j^0(x,y,z)\ket\lambda\) are "pure gauge" and they have a zero norm which is still harmless because probabilities may be zero. The operators \(j^0\) above have to be symmetry generators (time-like components of a conserved current) and not just some arbitrary operators because we want the labeling "\(\ket\psi\) is unphysical for \(t=0\)" to survive at later times \(t\), too. That's why the charge – integrated current – has to commute with the Hamiltonian. It has to be a symmetry and because it's localized in space and locally conserved, it's a local or gauge symmetry. If it were just some random operator, it wouldn't commute with the Hamiltonian and a ghost-free state at \(t=0\) would typically evolve into a state with ghosts at \(t\gt 0\). But we want to get rid of the zombies permanently!

In this way, not one but two polarizations out of the 4 polarizations of the photon become unphysical and only the transverse two polarizations, \(\ket x\) and \(\ket y\) or, in a different basis, \(\ket R\) and \(\ket L\) remain physical. Yes, the macro \(\backslash{\rm ket}\) is my most useful \(\rm\LaTeX\) macro I have ever created. It produces lots of cheap yet elegant fun.

Just a comment I won't need: the \(j=1\) field may be given an extra internal index \(j\), an adjoint index, e.g. \(j=1,2,\dots 8\) in QCD, and we will need to get rid of a greater number of ghosts (8 times in the case of QCD) so the conserved quantities have to possess this extra index, too: the conserved charges become generators of a non-Abelian group, e.g. \(SU(3)\) in QCD. Also, the gauge bosons may be made massive via the Higgs mechanism. If it is so, they have 3 and not 2 physical polarizations: the meat for the third one is obtained by eating a Goldstone boson.

Because we needed to get rid of one polarization of a photon for each \(k^\alpha\), we needed a current whose total charge is a scalar. What about \(j=2\) fields? If fields have two indices, the inner products roughly look like\[

\bra 0 a_{\kappa\lambda}(k)\cdot a^\dagger_{\mu\nu}(k)\ket 0 \sim g_{\kappa\mu} g_{\lambda\nu}.

\] There could also be permutations of the indices on the right hand side and/or symmetries, antisymmetries, or other constraints on the tensor. At any rate, we have two copies of the metric tensor. The one-particle state created by \(a^\dagger_{\mu\nu}\) will have a negative squared norm if exactly one of the two indices \(\mu,\nu\) is timelike. (We avoid the scary scenario in which all the doubly spatial components have the wrong sign: we couldn't get enough symmetries to kill the beasts.)

Fine, in this case, we need to get rid of the wrong "mixed" components \(a_{i0}\) so roughly speaking (ignoring the single \(a_{00}\) component which actually seems to have the right sign), we need a whole Lorentz vector of conserved charges. We know what such a vector of conserved charges could be: it could be the energy-momentum vector, associated with the spacetime translations via Noether's theorem!

In fact, if your theory is made out of local or nearly point-like particles, the energy-momentum vector is the only conserved vector you may have as long as your theory admits interesting interactions. For extended objects, you could also consider some kind of a stringy "winding number" but that would require a compactification or infinitely long strings so let's ignore this option.

To summarize, if we want to get rid of the negative-norm polarizations of symmetric \(j=2\) fields, such as the metric tensor, we need a gauge symmetry whose integrated charges transform as spacetime vectors. We need a conserved energy-momentum generating spacetime translations and we need to make its components local, i.e. make the generators independent for each point \((x,y,z)\) in the space. In other words, we need the diffeomorphism symmetry!

It's bizarre and cute. Our argument critically depended both on the Lorentz symmetry and quantum mechanics and we derived the existence of the diffeomorphism symmetry in a consistent theory – with non-negative probabilities – that allows you to create spin-two quanta! Isn't it cool? Gravity and principles of general relativity, perhaps broken in surprising ways, are inevitable parts of any consistent theory with fields whose spin is \(j=2\).

Why spins higher than two are not fine for elementary particles

What about \(j=3\) or higher? In that case, we would produce an even larger number of wrong-sign polarizations of the one-particle states created by the creation operators transforming as \(j\geq 3\) tensors. The corresponding conserved charges would have to transform as \(j\geq 2\) tensors. And they have too many components in \(d\geq 4\). In fact, if this high number of tensor components were conserved, one could prove that interactions are so constrained that they de facto vanish. Any momentum exchange between the lowest-mass scalar particles would violate the conservation laws.

This is the essence of the Coleman-Mandula theorem. There can't be conserved charges with spin greater than one. It follows – through our negative-norm-based arguments – that there can't be any fundamental fields with \(j\geq 3\) in your theory.

Well, string theory – and also its currenly fashionable "toy model", the Vasiliev higher-spin theory – circumvents this ban but the ability of these theories to avoid the conclusion critically depends on their having an infinite number of excitations with arbitrarily high spins \(j\) and their subtle interplay.

Let me mention that fields with spin \(j=5/2\) would have to come with conserved charges with spin \(j=3/2\) which is already too high and prohibits interesting interactions. So \(j=2\) is indeed the highest spin of "ordinary" fundamental fields.

Why the gauge symmetry for \(j=3/2\) fields is inevitably local supersymmetry

But as we mentioned at the beginning, there actually exists an integer or half-integer non-negative number – an allowed value of the spin – that is smaller than \(j=2\) and that we have omitted: \(j=3/2\).

Why have we omitted it? Because we were assholes. Some people would like to omit it even when they're reminded about their mistake. Those people are assholes even right now. I won't name all these Shmoits because I would have to throw up.

So how do our arguments work for \(j=3/2\) fields and what do they tell us about the required symmetries? Well, \(j=3/2\) fields look like \(\psi_{\mu k}\). One index is the Lorentz vector index, another index is a spinor index. They may be constrained by some extra conditions but those conditions don't kill too many components. Such fields are sometimes called Rarita-Schwinger fields and the particles they create are gravitinos but this sentence isn't assumed to hold in the following paragraphs.

Combining (and tensoring) our formulae for \(j=1/2\) and \(j=1\), we may determine that the wrong-sign polarizations of the field are created by the components with \(\mu=0\), i.e. \(\psi_{0k}\). Because the spinor index \(k\) may still take on any value, there is roughly one spinor of the required gauge symmetry generators at each point.

The conserved charges must transform as \(j=1/2\) spinors to allow us to kill the negative-norm states in an elegant way.

Are \(j=1/2\) conserved spinors allowed? Well, they have a smaller spin than the \(j=1\) energy-momentum vector so the answer seems to be Yes and indeed, below 12 spacetime dimensions, the answer is Yes. There can be conserved spinors. We call them \(Q_k\) where the index is a spinor index. And yes, let's say the word: they're generators of supersymmetry, the supercharges!

They're constructed out of fields that respect the spin-statistics relationship and because they're \(j=1/2\) spinors, they have to be fermionic, Grassmann-valued operators. We may ask what their anticommutators are. The anticommutator must involve a \(j=1\) conserved object:\[

\{ Q_{m},\bar Q^{n} \} = (\gamma^\mu)_m^n P_\mu+\dots

\] Ignore the bars and the difference between upper and lower indices if you're not experienced in the algebra involving spinors. The anticommutator of two \(j=1/2\) objects may contain a \(j=1\) object which is conserved as well. And I have already mentioned that the only sensible \(j=1\) "set of charges" is the energy-momentum vector.

(If the anticommutator were zero, the theory would be too trivial once again. Let me avoid this discussion.)

Moreover, we need to make the charges and currents local in spacetime, so we have just derived that a consistent theory with \(j=3/2\) fields has to contain both \(j=3/2\) currents for local supersymmetry as well as the \(j=2\) current for local coordinate transformations (diffeomorphisms) i.e. the stress-energy tensor. A consistent theory with \(j=3/2\) fields inevitably contains supergravity – because it contains both Einstein's gravity as well as (local) supersymmetry. Another article (one that has been written on this blog, in fact) may be written to prove that string/M-theory is the only consistent completion of supergravity.

Despite the extra restrictions, symmetries, and limitations, \(\NNN=1\) supersymmetric theories (supergravity coupled to super-Yang-Mills etc.) are compatible with all the known experimental constraints and conditions, assuming a viable choice of parameters. Nature could "discriminate against" the number \(j=3/2\) and omit this number from the list of "low spins" of allowed fundamental fields. But it would be bizarre, wouldn't it?

There is of course a lot of other circumstantial evidence why supersymmetry exists in Nature: dark matter, hierarchy problem, gauge coupling unification, its existence implied by string theory, and so on.

Jesus

Off-topic but funny: The Catholic Church has found a new heretic. Most scholars believe that Jesus was born between 6 years Before Himself and 4 years Before Himself. The new heretic wrote a book in which he claims that He was actually born several years earlier.

The name of the heretic is Ratzinger and he is employed as the Holy Father in a branch of the church somewhere in Rome, Italy.

This heresy is progress but if Jesus is supposed to have any relationship with Creation whatsoever, there are still 13.73 billion years of adjustments waiting in the pipeline.

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Stuart Freedman: RIP

Stuart Jay Freedman, UC Berkeley physicist, died at the age of 68. He joined Princeton in 1972 and Berkeley in 1991. A former particle theorist became an unusually versatile experimenter even though he used to dislike the Berkeley labs as "Big Science" (in a pejorative sense, similar to the "Big Government").



Picture via Rolf Kaltschmidt

A famous paper he wrote with John Clauser in April 1972 experimentally disproved local hidden variable models of quantum mechanics. The PRL document is wonderfully free of nonsense. They measure a correlation of photons' polarizations in calcium, verify quantum mechanics, and with some help from the CHSH inequality, they explain why local hidden variables couldn't agree with their results. Not too much conceptual progress occurred in that activity during the following 10 years when Alain Aspect got pretty famous by doing similar, slightly improved experiments.




A simple Google Scholar search tells you that he has done lots of experiments with neutrinos etc. In fact, he's been the boss of the Japanese neutrino experiment KamLAND.

RIP, Dr Freedman.



A 16-minute November 2011 talk by S.J. Freedman honoring Luis Alvarez (UC Berkeley, Nobel for NMR). Witty.

Something must be wrong at UC Berkeley these days. Five days ago, Robert Lin, experimental space physicist, died of stroke.

Plans of buildings on Google Maps

Off-topic: Google has added about 10,000+ interiors (list) to Google Maps. You just sufficiently zoom in. Check e.g. restaurants at the Logan International Airport in Boston.

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