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• Post #3124447

  The Austromarxism was a current of democratic socialism from the 1920s and the beginning of the 1930s. In 1919 the Socialdemocrat Party (SDAP) won the elections in Vienna, beginning the period of the "Red Vienna". Vienna was a Land, with great autonomy. It approved the 8 working hours, subsidies to unemployment, public housing (64 000 !), rent controls, public health care and education, new libraries and parks, more taxes to the rich (including a tax for having servants), etc....

• Post #3124445

  Interesting bit in Sean Carroll's last AMA episode. The Dirac equation is *not* a replacement of the Schrödinger equation, something many times implied or explicitly alluded. The Dirac equation is a classical equation for particles of spin 1/2 with electric charge, like the Klein-Gordon equation is a classical equation for scalars. The Dirac equation is more like Maxwell's equations with spin 1/2. When quantized, the Dirac equation gives you quantum field theory, and that&#3...

• Post #3124444

  So the question is, after finishing "Ring", continue with the Xeelee saga with Destiny's Children or jump to another Baxter's saga like "Manifold" (Time, Space and Origin).

• Post #3124443

  I'm going to move tomorrow to a new flat, after 15 years. Same city, but still... this puts me into a(n) (even more) philosophical mood. I'm slightly worried by the process. I don't have much: one table and one chair and the typical stuff for living (dishes, clothes, clutery, cleaning items...). What I have most are books, nearly 200. But even with that, I expect my moving to be easy for the company, compared with many others.

• Post #3124442

  Vacuum cleaners: automatic like a Roomba or manual:

• Post #3124441

  Something I learnt recently in the online course on quantum foundations I'm following is that, in the double slit experiment, you can put in one slit a vertical polarizer, in the other an horizontal. You'll get two bands, as expected, since you're measuring. But you can introduce, after the two slits with polarizers, diagonal polarizers, and you'll get the interference pattern! With the diagonal polarizers you don't know where the photons come from, you...

• Post #3124440

  My final grades after my third year learning German are 7.7/10. Certainly not bad, but they have been in descent during the course. I recognise that I don't study too much, but not due to laziness, but because I'm into many stuff. I like reading, learning more things about Physics (following a course on the Foundations of QM right now), there's work, socialising, dancing, exercise... I want to continue learning German, but I should probably think about it a bit more.

• Post #3124430

  TIL: there's a whale "speaking" in the 52 hertz frequency, where no other whale speaks or can hear. It has been called the "world's loneliest whale". It's argued that it can be a malformed animal or a hybrid, but it has been recorded since the late 1980s and it has been detected along many different places of the Pacific ocean, a sign of a healthy specimen. In 2010 another simultaneous recording of the 52 hertz song was detected elsew...

• Post #2314493

  TIL: the number of atoms outside galaxies is roughly the same of atoms inside galaxies. This is because of the long filaments or tendrils that emanate from galaxies and connect with another galaxies. These filaments are supposed to be like the tracers of dark matter, where the gas (normal atoms) coalesce. (From Daniel and Kelly's Extraordinary Universe podcast, episode: "Do we live in a super bubble?")

• Post #1698140

  The Foucault pendulum rotates due to the Coriolis force, that's something known from classical mechanics. But Padmanabhan (Sleeping Beauties in Theoretical Physics) suggests an intriguing analogy: you can also see it as a result of the parallel transport of the vector of the plane of the pendulum; if the pendulum would be in the Equator, it wouldn't rotate, there the Coriolis force is 0, but also it is a geodesic and the parallel transport doesn't change the vector. I love this kin...

• Post #1099010

  A historical TV series about how the solution of the cubic equation was found could work commercially. You would have mystery, love, treason, intrigue, and all of that in the historical and convoluted Italian Renaissance. (The solution of the cubic was perhaps the greatest new advancement in math in more than 1000 years, something that the classics never found).

• Post #856546

  I've watched "The Watchers", by Ishana Night Shyamalan, the daughter of M., who is one of the producers of the film. It's an horror movie, with some resemblance to The Village. It contains lots of frights and shocks that make your heart skip a beat, so don't watch it if this is uncomfortable for you. As with many of these kind of films, a considerable suspension of disbelief is demanded from the viewer. But it's a good movie, I think, and in th...

• Post #856545

  I think it was Penrose who suggested a version of quantum mechanics that was non linear due to the interaction with the gravitational field. But let's be honest, a fundamental theory worth its salt should be linear.

• Post #856544

  In his last AMA, Sean Carroll is asked if, as David Deutsch has claimed, the many worlds interpretation of QM is as sure as Darwinian evolution. Carroll says that no, that although his credence on the MWI is 90 - 95 %, his credence on evolution is much higher. He mentions two (for him) slightly weak points. On the one side, the problem of probability. I think he perhaps means how to derive the Born rule. He says he considers this solved but he's not 100% sure. And on the other side, the...

• Post #856543

  TIL: "vendeko" is a still not accepted prefix meaning 10^{-33}, near the Planck scale if we talk about meters. There are others, like vendeka for a positive exponent. And there're also xenno and xenna, 10^{-30} and 10^{30}. Also not accepted. I learnt this in Greg Egan's "Schild's Ladder". A quote by Douglas Hofstadter, from one his columns in Scientific American (On Number Numbness): "[...]If [the] numbers [have] millions or...

• Post #856542

  Beginning the third and last season of Dark. The series certainly maintains the high level.

• Post #856541

  Sean Carroll says in his last AMA that he has applied probably more than 50 times to different positions, and what he has received has been mostly rejections. In a society that only tells stories of successes, it's refreshing to hear from relevant figures (in this case in physics) about failure, a very natural state of we humans.

• Post #856540

  More interesting parts from Carroll's last AMA: the famous "it from bit" by John Wheeler is not that information is behind nature as a more fundamental layer of reality, as many who probably haven't read the original paper by Wheeler have said. Wheeler meant that the "it" came from collapses of wave functions (those were the bits). I guess this would eventually lead him to his participatory universe interpretation of quantum mechanics.

• Post #856538

  I think I've read so many sketches of proofs of Gödel's theorem that somehow they should amount to the full rigorous proof.

• Post #856537

  David Wallace is the half physicist, half philosopher that wrote that book about the many worlds interpretation of QM that had parts that were over me. Now he has a "new" title on the philosophy of physics that basically deals with: "the nature of space and time; the origin of irreversibility and probability in the physics of large systems; how we can make sense of quantum mechanics." Philosophy of Physics: A Very Short Introduction | Oxford Academic https:/...