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  1. L

    Higgs mechanism and vacuum instability

    Does the shape of the Higgs potential change if the energy of the vacuum changes? According to Wikipedia, If a more stable vacuum state were able to arise, then existing particles and forces would no longer arise as they presently do. Different particles or forces would arise from (and be...
  2. L

    Tunneling to a lower energy vacuum state

    Would the Higgs potential change shape if the vacuum changed to a lower energy state? It's apparently because of the unusual shape of the Higgs potential, where the highest-symmetry spot is not the lowest energy, that the Higgs boson can generate mass. So if the vacuum were in a lower...
  3. L

    Tunneling to a lower energy vacuum state

    Not knowing is totally different from knowing not. IF the vacuum tunnelled to a lower energy state, could this result in the disappearance of rest mass?
  4. L

    Tunneling to a lower energy vacuum state

    That's not what they're saying more recently. Apparently with a more exact idea of the Higgs mass, the vacuum is metastable (could tunnel to a lower energy state). Again, I'm not asking whether this is likely to happen anytime soon. Even if it takes a googol of years to happen, I'm still...
  5. L

    Tunneling to a lower energy vacuum state

    I'm not worried about it, I hope that rest mass could go away, if the vacuum tunneled to a lower energy state. The link you gave doesn't say what might happen to physics.
  6. L

    Tunneling to a lower energy vacuum state

    I read that the mass of the Higgs boson is such that we may be living in an unstable vacuum state, and if a region of the universe tunnels to a lower energy vacuum state, and eventually the whole universe would be in that lower energy state (ending life on earth). Do physicists have guesses...
  7. L

    Change in fine structure constant

    Here are a couple of references about effects on chemistry of changing the fine structure constant: http://pra.aps.org/abstract/PRA/v81/i4/e042523 http://ned.ipac.caltech.edu/level5/Hogan/Hogan3_1.html at least so far it seems like consequences for everyday chemistry aren't huge unless...
  8. L

    Change in fine structure constant

    Looking at the Schroedinger equation you can see that if \alpha is multiplied by F, then the potential V is multiplied by F^2; so if \Psi is a solution before changing the fine structure constant, then if you divide the length scale of \Psi by F, and divide the time scale of \Psi by F^2, you...
  9. L

    Change in fine structure constant

    Good point that it would change nuclear physics, because the ratio of electromagnetic force to strong force would change. Why would the periodic table change? Looking at the wavefunction for the 1s orbital of atomic hydrogen, it looks like if the fine structure constant is multiplied by a...
  10. L

    Change in fine structure constant

    What would be the consequences of slightly changing the fine structure constant, i.e. changing the strength of the electromagnetic interaction - but not changing gravitation or the strong force? In the everyday world? You might imagine that the strength of chemical forces etc. would change...
  11. L

    Medical Best advise: Don't google .

    I had a mysterious illness that I ended up self-diagnosing. See http://camoo.freeshell.org/allergies.html By googling and looking on Medline, I found there's a lot of evidence for local allergies, i.e. you can have an allergy to something even though allergy tests are negative. This could...
  12. L

    Accurate voltage control for motor

    This motor is a universal motor, does a universal motor have inductance? I asked Sola about voltage regulators and they said with an inductive load, there are short-term current spikes that might overload the voltage regulator, causing it to go to 0 V. So they say, for a motor the voltage...
  13. L

    Accurate voltage control for motor

    The line voltage is 120 V +/- about 5%, so it's already pretty good. Could I get somewhere a voltage regulator that takes 120 V +/- 5% and outputs a voltage accurate to +/- 1%, either as 120 VAC or some amount that you specify? Would the bench supply unit do that? Laura
  14. L

    Accurate voltage control for motor

    I get sick for several days when the turbine fails (allergies). But it's not life-threatening. Is there a good speed sensor for a universal motor? The utility voltage is pretty good - the engineer I talked to said it's usually between 120 and 124 V. Perhaps since the input voltage is...
  15. L

    Accurate voltage control for motor

    Again, I'd probably do fine with a sensor for the line voltage, then something like a rheostat that would be adjusted based on the line voltage. That's what I'm doing right now by hand. I have a voltmeter, and for a given line voltage, I know how the rheostat should be adjusted. It seems...
  16. L

    Accurate voltage control for motor

    It's an airline respirator, it pumps clean air to a facemask that I wear. If the air speed is too slow, the mask leaks. If the air speed is too fast, the turbine gets very loud. It's an industrial safety device that I'm using for a different purpose. Usually people when they use it, would...
  17. L

    Accurate voltage control for motor

    It would work well enough if I could tightly control the input voltage. However I don't know if there are voltage regulators that output voltage within +/- 1% that are reasonably priced. I asked about one, it costs ~$2700, which is too much. It likely has a lot of features I don't need...
  18. L

    Accurate voltage control for motor

    Is it easier to tightly control DC voltage? It's a universal motor, it likely can run on DC just as well ... The motor has a rheostat, so slow changes in the airflow/voltage ratio are OK. The variation I notice is from voltage changes. It would be accurate enough to measure the airflow...
  19. L

    Accurate voltage control for motor

    I have an air turbine, and it's critical that the motor speed be precisely regulated. It's very voltage-sensitive, so the fluctuations in the line voltage between 120-126 A make the motor speed too variable. How can it be regulated? A UPS might work. But it would have to output voltage...
  20. L

    Medical Why is Schizophrenia considered a disease?

    I wasn't claiming that it did, rather the opposite. I half-agree with the original point of view. Yes, I can see this view; but also, we live in a SEA of irrationality, and I prize real, honest, rational thought. Weird conspiracy theories, alien abductions, bizarre "medical" interventions are...
  21. L

    Medical Why is Schizophrenia considered a disease?

    There are lots of people around who are somewhat schizophrenic but not in hospitals and functioning in the world more or less. Like having delusions about the CIA having broken into your apartment; airplanes are watching you; hallucinations, scrambled thinking and talk. Like someone I knew a...
  22. L

    Exponential expansion and Higgs mechanism

    I saw papers online about the conjectured decay of the cosmological constant, i.e. tending to zero. If it can decay, it could grow also, I guess. Sure, the Big Rip would involve new physics. But so do other theories, including inflation. Laura
  23. L

    Review of Cycles of Time

    I put the following review of Penrose's new book Cycles of Time on Amazon as "Light Pebble". Penrose puts forth an old idea, that the end of our universe is the start of a new one, in a beautiful new way. That is, eventually the universe will lose track of the scale of space and time. Then...
  24. L

    Exponential expansion and Higgs mechanism

    The dark energy could be the cosmological constant, which isn't matter. That could decay or grow.
  25. L

    Exponential expansion and Higgs mechanism

    Why would it require negative-mass matter? It's just the idea that dark energy, whatever that is, is getting stronger.
  26. L

    Exponential expansion and Higgs mechanism

    It has? On a quick web-search, I found something http://www.universetoday.com/36929/big-rip/" the likelihood of the Big Rip ever taking place is substantially diminished because evidence indicates dark energy isn't growing in strength. This doesn't sound very definitive though, and I didn't...
  27. L

    Exponential expansion and Higgs mechanism

    If the cosmological constant were increasing in time, there could be a "Big Rip" where eventually all matter is torn apart, and perhaps the Higgs mechanism that creates rest mass would be destroyed. I guess that wouldn't de Sitter space, it would have some other geometry. Laura
  28. L

    Casimir operators and rest mass

    Penrose says in “Cycles of Time” that rest mass isn't exactly a Casimir operator of the de Sitter group, so a very slow decay of rest mass isn't out of the question in our universe. If rest mass is strictly conserved, should it be a Casimir operator of the de Sitter group? Decay of rest...
  29. L

    Exponential expansion and Higgs mechanism

    I see. I thought the horizon would shrink since the expansion is exponential, but I guess not. Laura
  30. L

    Exponential expansion and Higgs mechanism

    Our universe apparently has a positive cosmological constant so it will look more and more like de Sitter spacetime, expanding at at exponentially increasing rate. So eventually it seems that subatomic spacetime would be affected by this. Eventually even something a Planck distance away would...
  31. L

    Eventual disappearance of rest mass

    If the universe were expanding very, very rapidly, would rest mass disappear? I've been reading "Cycles of Time" by Roger Penrose, which is about his "conformal cyclic cosmology" theory. The gist of it is that in the VERY VERY distant future, like a googol of years from now, when all the...
  32. L

    Medical My mental illness symptoms as a child

    I used to know somebody who told me he had schizophrenia as a child. I don't remember what his symptoms were. I asked him what his parents were like, and he said dismissively that they were "nonentities". I was abused horribly as a child, and I thought that was strange and alienating that...
  33. L

    Japanese Earthquake - was it really that devastating?

    I think leaving a large ship there as a memorial, with a museum built into it and all sorts of pictures of the disaster and tsunami devastation, would be rather beautiful. Like this one: http://i.telegraph.co.uk/multimedia/archive/01852/ships-620_1852083i.jpg It needs to be fixed up a...
  34. L

    Japanese Earthquake - was it really that devastating?

    I mean, ships are built near the water. It would be rather hard to tow such a thing around.
  35. L

    Japanese Earthquake - was it really that devastating?

    Geologists actually didn't expect that fault to have such a big earthquake. http://sciencenews.org/view/generic/id/71281/title/Japan_quake_location_a_surprise People were not prepared at all for the giant tsunami that resulted. A similarly huge tsunami happened in 869 and in 2001 researchers...
  36. L

    Japanese Earthquake - was it really that devastating?

    The Japanese earthquake wasn't just "rather strong", it was gigantic! Magnitude 9. For comparison the "Big One" that's expected to strike Los Angeles soon would be about a magnitude 8. That's 1/32 as much energy as this earthquake! The San Andreas fault near Los Angeles is capable of about...
  37. L

    Sun - Increasing in Luminosity

    The book by Jeffrey Kargel "Mars A warmer wetter planet" has a long description of what's expected for Earth in the future, climate and evolution of life. And for Mars. I doubt the part about what will happen to life in the future is very accurate because it's based on the past adaptations to...
  38. L

    Vagina dentata question

    Here's a http://onlinelibrary.wiley.com/doi/10.1111/j.1471-0528.1987.tb03132.x/abstract" [Broken] If somebody can access the online content and tell us more about what's in the case report, please do. And one unfortunate woman had teeth coming out of...
  39. L

    Maximising the area of a triangle of known perimeter

    You can do it by finding the minimum perimeter of a triangle given a fixed area.
  40. L

    Anti de Sitter space and black hole information

    So a string theory with gravity in anti de Sitter space apparently resolves the black hole information paradox via the adS/CFT correspondence. I'm wondering: is the anti de Sitter space somehow necessary to string theory with gravity? Or is it just because there's this adS/CFT correspondence...
  41. L

    Beautiful geometry proof

    I apparently can't edit that posting any more. But the link to the pdf with the other person's proof has changed, to http://www.artofproblemsolving.com/Forum/download/file.php?id=27177" [Broken] Laura
  42. L

    Beautiful geometry proof

    Assign to each side b of a convex polygon P the maximum area of a triangle that has b as a side and is contained in P. Show that the sum of the areas assigned to the sides of P is at least twice the area of P. This was a 2006 Math olympiad question. A beautiful proof is at...
  43. L

    Special relativity or QM video games?

    Huh. I mentioned this idea in a job interview with Mattel or someplace like that, in the 80's. The interviewer just grimaced - apparently thought it was a nerdy idea. :frown: I got no job offer. Shows that local stupidity doesn't imply global dryness :tongue: I think it would be a great...
  44. L

    Quasicrystal growth

    There are "quasicrystals" with fivefold symmetry in the crystal diffraction pattern. They're aperiodic in a systematic way, similar to Penrose tiles, which tile the plane in a five-ish way. The pattern doesn't have translational symmetry, but you can get the pattern to correspond as closely as...
  45. L

    Elegant complex analysis

    I don't think that's true. Q_p[i] is a quadratic extension of the p-adics, and it has Cauchy-Riemann equations, but it doesn't have the nice theorems like Cauchy integral theorem, residue theorem, maximum modulus. But \Omega_p, which is algebraically closed and contains the p-adics Q_p, does...
  46. L

    P-adic analysis question

    I looked into it some more - Derivatives are used in the p-adics, although "strictly differentiable" is a more useful concept than "differentiable". Strictly differentiable at a point p means that as x and y approach p, then f(x)-f(y)/(x-y) approaches f'(p), the derivative of f at p. If...
  47. L

    P-adic analysis question

    The p-adic numbers Qp don't have a square root of -1, if p=3 mod 4. So would differentiable functions from Qp[i] -> Qp[i] satisfy the Cauchy-Riemann equations? I don't know why not. To what extent would analysis in Qp[i] have the familiar complex analysis theorems? You couldn't prove that...
  48. L

    Elegant complex analysis

    The Cauchy-Riemann equations are a consequence of the particular polynomial x^2+1=0 that i satisfies over R. If you were extending analysis in a field F to some other field G of finite index over F, where G=F[a] and a satisfies some other polynomial over F, then you'd have a different set of...
  49. L

    Elegant complex analysis

    being real analytic does not give the strong results that being complex analytic does. So I'm wondering if that's related to the algebraic completeness of complex no's.
  50. L

    Elegant complex analysis

    Complex analysis has a lot of nice theorems that real analysis doesn't have: if you can take the complex derivative once, you can take it \infty many times. Maximum modulus theorem; inside the radius of convergence the Taylor series of a function converges to the function. So what I wonder is...
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