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joigus

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Everything posted by joigus

  1. How can an event be free-falling? You do not Lorentz transform an event, but its coordinates. And you do not Lorentz transform them "towards" anything. You use the language in a way that makes it very difficult to understand what you mean. It is totally wrong though, to assume that Lorentz transformations give rise to vacuum fluctuations, as Lorentz transformations simply represent changes in the point of view. There are subtle questions related to whether the physical vacuum --which has to do with quantum fluctuations-- is invariant under Lorentz transformations, but that's a completely different matter, and doesn't sound it's what you have in mind.
  2. Genady is right. It's not a transcendental equation. I made a mistake. Sorry. Somehow I thought I saw an "a" in the first term, which wasn't there.
  3. This is a transcendental equation. You cannot solve but by means of approximate methods, like iterations that are known to converge to a solution, etc.
  4. It wasn't much of a problem for Hermann Weyl: Raum, Zeit, Materie Space, time, matter I'm starting to suspect the problematic word to many people is not "what", nor is it "physics" It's probably "is." What is "is"?
  5. The gift that keeps on giving.
  6. HUP is part of the foundations of QM, and a very important one. But you cannot get all the richness of results of QM from HUP alone. It's like saying that all of Euclidean geometry can be obtained from the pythagorean theorem, or all of art from mastering perspective.
  7. It doesn't. Laser is based on photons being bosons rather than fermions, transistors have to do with non-linear response (non-Ohmic circuit behaviour), internet and computers could have been developed if the world were classical, AFAIK. It plays a part in Zenner diodes and the like --tunnel effect-- AFAIR, but not singlehandedly, let's say. HUP does not "explain" these things AFAIK. Who told you that?
  8. Make Homo sapiens great again?
  9. https://www.genecards.org/ https://www.ncbi.nlm.nih.gov/genome/guide/human/ ...
  10. Huh... I wasn't making a point. It was a simple question. What is a waveform? Is it a wave function? Is it the equivalence class of all gauge-equivalent wave functions? Is it the modulus square? I'm not familiar with the concept.
  11. It's been a long time since I first understood the difference between being able to explain something, and being able to give a name to something. Eg, is what you're saying now subject to dialetheism? That is, can I believe, or trust, or take for granted what you're saying now, and not believe, not trust, not take for granted anything you're saying now, both at the same time? Is dialetheism itself true and not true? Can it be applied to itself? In the words of Sir Humphrey Appleby, I foresee all kinds of unforeseen problems...
  12. Real excludes "non-real". Therefore it excludes "real and non-real". Unless you're speaking from a different kind of logic. Fuzzy logic, etc. 1) Identity (A is A) 2) Non-contradiction (A is not the neg. of A) 3) Excluded middle (B always is either A, else neg. of A) As to entanglement, etc, I concur with @MigL and @Genady. It certainly doesn't multiply information. If anything, it "compresses" it, whatever that would mean. What it does, perhaps, is bring a brand new kind of entropy to the game: Entanglement entropy => more ways in which we can be ignorant.
  13. Doesn't the question, "Why are there so many insect/small arthropod species?" have a heavy bearing on the OP question? In different patches of ground in Hawaii there are different species of Drosophila alone. 416 only i Hawaii, and only in this genus. For an insect --or any other small arthropod-- a patch of forest, or a particular layer of habitability could be in the range of meters/centimeters, etc. Bacteria --prokaryotes in general-- are pre-sex, so... What is a species, YKWIM? Eg, are two bacteria with different plasmids the same species, and therefore expected to be subject to comparable mathematical constrictions?
  14. Stenography
  15. I don't know. In QED there is no curvature, and no gravity. Kaluza-Klein did propose a generalisation of GR meant to package EM and gravity together. Einstein liked it at first but for some reason found problems with it. Every now and then people revive the idea for model-building purposes... Yang-Mills is a generalisation of electromagnetism, rather than gravity. It's what gives rise to weak and strong interactions. In all these YM theories we have a group of symmetry that defines the particles, their properties, how many there are... Everything. In the case of EM it does remind one of Kaluza-Klein's idea in the form of an internal dimension, because the group is U(1), which is the group of symmetries of a circle. But the group for electroweak is U(1)xSU(2)L (L for "left") is bizarre in terms of a Kaluza-Klein kind of thinking. Today, these extra parameters are sometimes referred to as "internal", but I don't think anybody thinks about it in terms of dimensions. They're rather quantum numbers. Further physical variables and conserved quantities.
  16. Nah. It's not physics that's stagnated. It's string theory. Physics is not just superstring theory. Physics is not just unification or superunification or cosmology either. Physics is not just theoretical physics. Has the pace of theoretical physics slowed down considerably in comparison to other branches of physics? Arguably, yes. I think humanity periodically loses vivid memory of the 'intelectual turmoil' of past times. It's normal. Before the next revolution there's a time when this intelectual territory is up for grabs, and people start staking their claims. Superstring theory has not lived up to the expectations. So what? The most dangerous man in the world? Witten is a mathematical physicist that's turned out to be more useful to mathematicians than to physicists so far. He didn't win a Nobel Prize, but he did win a Fields Medal. Michio Kaku is out of control? Is he publishing dangerously? 🤣 Gimme a break! The way I see it, this is like the centuries between Galileo-Newton and Faraday-Maxwell, when nothing new in physics seemed to appear, but robust and powerful progress in the formalism was accruing. People, be patient. It's not gonna be you, it's not gonna be in your lifetime, it's not gonna be your pet theory that gets chosen. What's going on is not making the headlines, it's not on the podcasts, it's not on TV, that's all.
  17. I do too! If I like the wine, and I like the fish, why would one ruin the other for me? I do feel that certain wines seem to go particularly well with certain foods. A young red wine and sufficiently ripened cheese are a great combination. And and red wine aged in oak and red meat too. But there's no reason not to break the 'rules' if you happen to enjoy it.
  18. The grape, the brand and the vintage give you an approximate idea of what to expect in terms of price range. But I agree with @MigL: "Drink what you like" By that I mean: It's often the case that the wine I like the most is not necessarily the most expensive one, once grape, vintage and the particular vineyard have been factored out of the equation. You never know what goes in the price tag. There are, I suppose, as many factors as a particular producer can meet in trying to make each bottle profitable. If you can produce wine of a certain quality standard, but you only have one hectare with the right slope, sun exposure, blah, blah, maybe your pricetag will skyrocket for no apparent reason on the consumer's end.
  19. This is unknown, and it quite depends on what is the level at which you want to answer the question (biological?, social?, etc). A good starting point for you to start getting some ideas is, as always: https://en.wikipedia.org/wiki/Origin_of_language If I had to pick a guess, I'd say it starts by correlation between gestures and other sensorial pieces of input and vocalisations (as @Sensei suggested), and the connection being "confirmed" by developing the neural connection during the growth of an individual. Many animal species have alert calls that are specific to the kind of threat. So there's this, and then there's also parental reinforcement, etc, which isn't essentially different IMO. A Google search "how did language start?" produces: From there, it could be argued that any cognitive refinement that helps remove ambiguity by using sound codes (or, in fact visual codes, like in sign languages) would be highly favoured from an evolutionary POV. For that to happen, the brain has to be wired properly. So: From a biological perspective, it seems to be related with lateralisation of the brain: https://en.wikipedia.org/wiki/Lateralization_of_brain_function And then, for higher language function we have the highly specialised FOX-P2 gene. Relatively recently, it was discovered that mute children who live in some kind of (restricted, mute) society, spontaneously develop a sign language: https://en.wikipedia.org/wiki/Nicaraguan_Sign_Language Think about it --and this goes in the direction of @exchemist and @Genady--: If you grow up in France, what are the chances that you will end up saying fenêtre instead of "window"?
  20. Curvature is frame-independent. If there is curvature in one frame, there is curvature in every frame. By going to a reference frame that compensates for that acceleration, you would go back to an inertial frame.
  21. They would be there, but be too minuscule to measure. That's one of the reasons why LIGO was such a challenge.
  22. No. Gravitational waves any sizeable would only be produced by extremely violent astrophysical processes, like BH collisions or the Big Bang. There is something called gravitomagnetism in which gravitational waves are included, but also includes other gravitomagnetic phenomena, like frame dragging. Maybe that's what you have in mind.
  23. Yes. When physicists talk about simplicity, what they mean is most phenomena --perhaps all-- can be understood in terms of very simple principles. It's the constant overarching theme of a swathe of apparently different phenomena boiling down to very simple principles. The devil, of course, is in the details. And the very sophisticated formalism one has to learn first --and here's where the steep learning curve comes in--, in order to see how beautifully simple and economic the abstract formulation is. Thus, one could say chemistry is basically about exchange of electrons (red-ox) and protons (acid-base); physics is about minimising the action. We all know it's "just" about this. And as to geology and biology... Bad example. Biology and geology are genuinely complex. Complex in every sense.
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