Genus 5+ supermoduli space is not split

In multiloop diagrams, superstring theory is more than bosonic string theory with a cherry on a pieThree weeks ago, I discussed the possible shapes of the two-dimensional torus. They were parameterized by the parameter \(\tau\in\CC\) with an extra symmetry, "modular invariance" \(SL(2,\ZZ)\), identifying countable sets of values of \(\tau\).The torus may be considered as a genus-one Riemann surface (a sphere with \(h=1\) added handle to it) and it...

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Herschel retires

...and other events and anniversaries...The Herschel Space Observatory lost its ability to see after four years: Science World Report, Google News, Herschel on TRF. The life expectancy, 4 years, is pretty short, isn't it? What was the reason why Herschel had to end its mission? Well, it ran out of the liquid helium coolant. Such things are finite. Incidentally, I think that the general claims that we're running out of helium on Earth are heavily...

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PhysX PBF: breakthrough in simulation of water

A decade ago, the state-of-the-art computer simulation of moving water looked like the 0:20-0:40 segment of the Mafia I trailer. In the following years, the progress was relatively modest up to very recently.PC games have become nearly photorealistic but flowing and splashing liquids are still hard. In some sense, one needs to simulate individual (enlarged) molecules and/or the Navier-Stokes equations – both tasks are difficult when it comes to the required computer power etc.See also a lighthouse etc. and one more bunny bath.The video above shows...

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Democritus on the QM operating system

Comments on some extra chapters were added at the endThis reading report will be much more favorable than the previous one, one on minds and machines.Chapters 5, 6, 7 etc. are dedicated to the classes of problems that may be solved in a reasonable time. They are full of arguments showing that if one type of a problem may be solved [at all AND/OR with some limitations on time AND/OR with some limitations on memory AND/OR with some probability of success AND/OR with some secret hints etc.], then another type of a problem may be solved at all.This...

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Gordon Kane: Supersymmetry and Beyond

You may pre-order Gordon Kane's book, Supersymmetry and Beyond, that will be released on May 14th. It has about 200 pages, a foreword by Edward Witten, a glossary, and recommendations from Brian Greene and David Gross.An appendix discusses the prediction of the Higgs mass from compactified string theory.Chapters of the book introduce you to the contemporary physics, the Standard Model, its known elementary particles and their hypothetical superpartners.But you also learn why physics is the easiest science – and, which is related, what is the effective...

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New Czech president attacks EU regulation

A way to summarize why I have been decided for quite some time to vote for Miloš Zeman as Václav Klaus' successor is to say that among the candidates who had a significant chance, he was the most right-wing one. He was the clearest for of the green politicians and NGOs; he was the most candid one when it came to jokes vs political correctness; he is a much stronger hawk when it comes to foreign policy (especially the threats posed by the Muslim world)...

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New accurate gravitational wave data

A new pulsar and his white dwarf pal confirm Einstein's GR againThe 1993 Nobel prize in physics was given for the discovery of a binary pulsar, i.e. a rotating neutron star, whose orbiting frequency was changing exactly as predicted by the general theory of relativity which says that accelerating masses emit gravitational waves, lose energy, speed up the orbiting rate, and gradually collapse onto their companion.Now, 20 years later, astronomers found a new strange couple called PSR J0348+0432 that allows us to run these tests more accurately than...

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Hyundai ix35 unfit for suicide by CO2

All the media have informed about the following Hyundai ad that was quickly suspended:The man tries to commit suicide by inhaling the gases from the exhaust pipe. But Hyundai ix35 only has "water emissions", whatever it exactly means, so he fails.Understandably, some people – including surviving dependants of people who did commit suicide in a car – were upset. Well, suicides are present on the maternal side of my DNA chain but I wasn't offended....

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An apologia for firewalls

Anniversaries: there are lots and lots of birthdays and deathdays of mathematicians who influenced physics today, including Felix Klein, Siméon Denis Poisson, Andrey Kolmogorov, and Felix Berezin.A decade ago, I would enthusiastically read many or most papers authored or co-authored by Joe Polchinski who would be a fountain of crisp, creative, and perfectionist physics. I may have voted for him as the world's #1 most clearly thinking physicist.Sadly...

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Lee Smolin: Time Reborn

An incredible pile of unscientific gibberishThere's one aspect in which Lee Smolin's newest book is less irritating than his previous book, The Trouble With Physics: the main purpose of the new book isn't to mindless attack and lie about the best results of the contemporary theoretical physics research. Instead, if we ignore the mega-arrogant and super-dishonest subtitle "From the Crisis of Physics to the Future of the Universe", "Time Reborn" tries to attack physics from the times of Newton and "constructively" present Smolin's own ideas about...

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Minds and machines

Let me say a few words on the fourth chapter of Scott Aaronson's book, Minds and Machines.It's about complexity of problems as well as the differences (or equivalence) between human brains and artificial thinking machines.When one reads this fun stuff, he may see how these complexity folks are thinking and – even if he knows the principles – he realizes which of them are considered important (and, in many cases, more important than they deserve) by the complexity theorists. I would say that not even Aaronson would claim that this chapter has anything...

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