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Everything posted by Strange
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Quantum theory inlcudes special relativity. It doesn't work without it. I know you think that "mathematics" is a dirty word, but it is an essential part of science and engineering. (Including computer science, so I am surprised you are not more familiar with it.) Sorry, I don't know what that means. I'm not sure why you joined a discussion forum then. But it isn't about "winning". I haven't tried to explain relativity to you as I don't think I could do it any better than the thousands of popular (non-mathematical) books, articles and websites out there. I just want to show that it is an essential part of all of modern physics and much technology. It works. If you don't like it, well that's just too bad, really.
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You are mixing up speculative, almost sci-fi, ideas like time travel and "holes through dimensions" (whatever that means) with an apparently very confiused idea of time dilation and then rejecting the theory because those things don't make sense. So ultimately it comes down to the fact that you think the theory is wrong because you, personally, don't understand it. That isn't how science works.
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Solar sails are not able to accelerate things to speeds where relativistic effects become noticeable so their effectiveness won't be affected by this. One of the places where we are able to accelerate things to a significant fraction of the speed of light is in particle accelerators (like the LHC). In this case, the increasing amount of energy needed to keep accelerating the particles is exactly what is predicted by relativity.
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Designing computers relies on quantum theory (for the design of semiconductor materials and devices such as transistors) which in turn is based on special relativity. The mathematics of special relativity is very simple, so even someone with little maths background should be able to understand it. (But I don't understand how you can be a "computer student" without studying maths.) The maths of general relativity is much, much more complicated -- well over my head. The concepts of special relativity are also fairly simple. But it sounds as if you are rejecting the idea for strong emotional reasons and hence not thinking the explanations through in order to understand them. Maybe you just need to accept that it is never going to make sense to but "it just works" anyway.
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Maybe you need to explain what you think these words mean, because this is obviously not true (given the standard meanings).
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There is no evidence that thiomersal is toxic: http://www.who.int/vaccine_safety/committee/topics/thiomersal/questions/en/
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I have never heard of "rainbow gravity". I am fairly sure there is no evidence for the wavelength-dependent dispersion that it predicts (but I can't find any references for this right now).
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So it sounds like (1) and (2) are just different ways of describing the same effect?
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Could you summarise what you think are the main flaws of GR?
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Did you miss all the other evidence that you have been given for dark matter? Is that why you have refused to provide an explanation? Do you need it listing again? It means matter that is not made of baryons (protons and neutrons, for example). It also cannot be charged leptons. That will be because of the large amount of evidence. And because it solves a number of other problems in physics. Instead of showing yet another made-up graph, why can't you do the quantitative analysis that has been requested? Is it because you are not able to? Or have you done it and found it does not support your theory? No it isn't.
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Yes, you can always model the mass inside the orbit as being at the centre. The thing is that for the solar system, the central mass inside every planet's orbit is the same (the mass of the sun; the mass of the planets is insignificant). In the case of a galaxy with a distribution of dark matter throughout the galaxy, then there is more mass inside the orbit the further out you go. So at each distance that "central mass" increases. So they are not all orbiting the same central mass. And so they don't follow Kepler's laws.
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Kepler's law (only) works for a central point mass. This is an accurate model for the solar system, for example. It is (or was thought to be) a reasonable model for a galaxy once you get far enough outside the central hub that it can be treated as the only significant mass around which the stars orbit. However, if there were a lot more mass distributed throughout the galaxy then, as you move further away from the centre, there is more mass inside the orbit affecting the orbital speed. As you move out, more and more mass is added so you get a non-Keplerian distribution of velocities. The visible matter is not enough to have a significant effect and so you would still get the near-Keplerian fall-off of speed. The observed effects can be explained by the presence of non-visible matter. The required distribution of this matter, matches that obtained by modelling the behaviour of this matter. So it all ties up quite nicely. Lots of people have tried the "new law" approach. So far, none of these have been able to match the evidence. For example, MOND (the best known example) requires a different set of ad-hoc adjustments to work with galaxies than it does with galaxy clusters. And then it doesn't explain gravitational lensing. Or large structure formation. Or ...
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Although X-rays a very useful technology, in medicine and industry, they have not had anywhere like the impact on science that others have. The 2009, 2010 and 2014 Nobel Prizes (among others) are for work that might turn out to have just as great, or greater, practical applications. The Curies' work was more important in understanding the nature of matter; Einstein's Nobel prize was for work that completely changed the nature of physics. And so on.
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And there's the thing. If there were just a central mass (or an approximation to one, in the central bulge) then you would see a fall off in orbital speeds (yes, approximately Keplerian). But that is not what we see. What is observed is behaviour that is consistent with a large amount of mass distributed throughout the entire galaxy. So, in a sense the "obvious" (easy) solution is to say there is that distribution of matter but we just can't see it for some reason. Hence the name "dark matter". Early on it was not clear that "dark matter" was actually matter and many other hypotheses to explain the effect seemed plausible. More evidence has changed that, so it now seems almost certain that the extra mass is some form of matter. And that it is not just hard to see (e.g. minute black holes, cold dark stars, etc) but actually non-interacting. There are a lot of scientists who are unhappy about this. (And some who a really excited.) But that is the way the evidence is currently pointing.
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A nice silk moire or a more chunky Harris tweed?
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OK. Sounds like I was wrong. I am surprised that Kepler's laws can be used as an approximation that close to the centre (although they don't say what "a few kiloparsecs" is). No, I just overestimated / misremembered / misunderstood (*) the significance of the mass in the disk. (*) Take your pick. More than twice. However, Kepler's law does not apply closer to the centre (as that article confirms). But it does in the case of planetary orbits. Beejewel does a curve fit (the red line) between zero (the Sun) and the first planet which has no physical meaning and has no supporting data; it is just there to make it look similar to the rotation curve of galaxies. So if you are going to accuse people of dishonesty, why not start there?
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I'm not sure what other options there are. Surely it is either deterministic or not? So, deterministic then. As long as your "modification function" allows for some element of randomness (i.e. next states can only determined with a certain probability) and for some calculations to be observer dependant, then that seems like a reasonable (if very crude) description of the universe. If the "next state" was not dependent on the previous state. For example, in our world, when I toss a coin the result is either heads or tales, in a completely non-deterministic world, the result of a toss might be that the coin disappears or turns into a blue whale or dragons fly out of my nose or ... So a bit like weather forecasting or the many other sorts of computer modelling we do? Quoting my previous post in response: *possibly as a seperate thread
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I assume we can we take your repeated refusal to produce a quantitative comparison of your predictions, current models and reality to mean that your model doesn't work.
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Only if you ignore all the fundamental flaws. Which you are doing a brilliant job of, by the way. Dirac only guessed that might be the case because there were no other obvious candidates at the time. He knew the different mass was a problem. If the positron had already been discovered, he would have correctly identified that as the anti-electron. It was Oppenheimer who pointed out that hydrogen atoms would instantly annihilate and thereby convinced Dirac that the proton could not be the anti-electron. He therefore predicted the existence of the positron (which was discovered the following year). This has nothing to do with "coming from a respected scientist". If you really believe that you have a very warped idea of how science works.
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Does this hold true for all Prime products? / RSA isn' the encryption...
Strange replied to Trurl's topic in Mathematics
The whole point about a public key is that is public. So if someone steals it from your PC, no problem. If you are really concerned, then keep your private keys on a non-networked computer and use that to do all encryption. Then copy the encrypted message to your networked PC in order to send it. -
Actually, it isn't an "easy" solution. It has taken decades of work to understand its properties, determine the distribution, understand its role in structure formation, etc. And we still don't know what it is (and, of course, alternative explanations are still being explored). So, no. Not easy.