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Everything posted by Strange
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Fresnel's Transmission and Reflection equations.
Strange replied to reerer's topic in Classical Physics
where did you copy it from? -
There is no "fig 7" What is AMI? What is CP? What is dz? What is nn'? What is KCL? Where did you copy that text from? What is the point of this thread? Carl? Is that you?
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It can't be baryonic because if it were, it would interact with electromagnetic radiation.
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Light can be closed in a mirror's box?
Strange replied to Darko Dark Shadow's topic in Classical Physics
It will be absorbed by the mirrors because they are not perfect reflectors. If you could create a perfect reflector then, yes, the light would stay in there forever bouncing around. But that is not possible. -
Well, I hope no one makes the mistake of buying your book thinking they will learn any science.
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No. Because not all interactions are scattering. Scattering is one specific type of interaction. (Or class, as there are several types of scattering. But none of them are refraction.)
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These ideas can be easily distinguished. There is evidence that gravity is due to the presence of matter (or, strictly speaking, mass). There is zero evidence that matter can be created by gravity. So we do not agree. Gravitational waves (not gravity waves, which are something different) are created by the interactions of masses. Gravity from the gravitational field requires some mass to create the gravitational field in the first place. So these are not independent of matter. That seems rather contorted logic. And there is no evidence to support your conclusion. Not sure what that means. What is a "continuum between matter and energy"? They are completely distinct things. Where do you get that from?
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Another article on why modified gravity theories don't work: https://www.forbes.com/sites/startswithabang/2017/10/25/merging-neutron-stars-deliver-deathblow-to-dark-matter-and-dark-energy-alternatives/#6d9542453b8c Supported by the recent neutron star merger.
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There are non-mechanical ways of storing potential energy. For example, you could charge a capacitor. And then use the current through a child to impart kinetic energy to a magnet. I don't know if that is any closer.
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If your suggestion is that the self-gravitation of the gravitational field is the explanation for dark matter, then that is a testable hypothesis. I would suggest your first step (as you are not able to calculate the size of this effect - and neither am I) would be to look for any published work on this. I suspect there isn't any because (and this is just a guess) it is such an obvious idea that I would imagine almost every cosmology or astrophysics graduate would have thought of it. They would do a quick back-of-the-envelope calculation and find it is eleventy-squillion times too small. But who knows. There are lots of scientists who do public outreach on blogs and twitter. You could try asking one of them - if they think it is interesting (or enough people have asked) they might even write about it. But you need to do this as a "is it possible that" question rather than "my theory is". Otherwise your question will be deleted without consideration. (See Katie Mack's FAQ for a good explanation of why.)
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I don't think so. They are less likely to hit each other! And less likely to be attracted to one another. If they were small enough, maybe the Hawking radiation might have a significant effect - pushing them apart?
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I think they should be the same (and I assume one could show this from the equation for gravitational time dilation). I haven't tried it but I think if you apply the Lorentz transform to the equation for escape velocity (which is the same as the speed when falling from infinity, which is your 11.186km/s) then you should end up with the equation for gravitational time dilation. Because equivalence. There is a big difference between not being refuted on an Internet forum and being mainstream science! Turns out to be pretty straightforward: Escape velocity: [latex]v_e = \sqrt{\frac{2GM}{r}}[/latex] Lorentz transform: [latex]\frac{1}{ \sqrt{1 - \frac{v^2}{c^2}}}[/latex] Substitute for v: [latex]\frac{1}{ \sqrt{1 - \frac{\sqrt{\frac{2GM}{r}}^2}{c^2}}}[/latex] Simplify: [latex]\frac{1}{ \sqrt{1 - \frac{2GM}{rc^2}}}[/latex] Which is the equation for gravitational time dilation.
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Don't be silly. Then you need to provide some evidence for you claims: such as "curvature of space-time increases the density of space, and therefore may create mass which gives rise to matter". Or that your idea can explain dark matter or dark energy. For example, you need to show how your idea can reproduce the observed rotation curves in galaxies. Or that it can produce the observed acceleration of expansion.
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Actually, black holes "normally" produce Hawking radiation. And the black hole resulting from such a collision would emit less (because it is inversely proportional to mass). The collision would produce gravitational waves, at least in the "ring down" phase after the collision (this is where the merged black hole settles down into a sphere again). As far as I know, there is no mechanism for black holes to get smaller. For example, if your black holes did not collide head on but skimmed past each other, then they would either merge or they would emerge unchanged (apart from their directions being changed by the gravity of the other). It couldn't "tear off" a mini black hole from one of them.
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Well a hydroelectric generator system converts potential energy to kinetic energy and then to electricity. And the process can be reversed to store energy. Aren't springs man made? If they don't count, I'm not sure what does.
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The word asymmetry is being applied to two different things here, which is potentially confusing. The thread title is referring to the asymmetry in the amount of matter and antimatter (which obviously does exist). The article you link to highlights that, as expected, anti-protons are identical to protons; i.e. there is no asymmetry in their properties. That is whey we expect there to be symmetry in the amount of matter and antimatter: in other words to be equal amounts of both (i.e. none).
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That doesn't mean I agree with what you claim the source of gravity is (whatever that is, it isn't very clear). I hope you are not deliberately putting words in my mouth. When did I say that gravity is not linked to mass? Your seem to be twisting what I said to fit.
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There is a slightly clearer example here: https://phys.org/news/2017-10-physicists-quantum-gravity-current-technology.html But not much ...
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Although some people may claim that, it isn't the general opinion of "psychiatry" (if a branch of medicine can have an opinion). https://en.wikipedia.org/wiki/Joan_of_Arc#Visions
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That single point (singularity) is what happens if you trace back the expansion using only general relativity. No one expects that the universe actually started as a single point. And such a point could consist of matter (because matter cannot be compressed to a point). The problem is with the initial creation of matter (or, strictly speaking, baryons and leptons). If you assume matter already exists, then you are starting from a time after the problem existed. https://en.wikipedia.org/wiki/Chronology_of_the_universe#Electroweak_epoch When matter is produced from high energy photons, for example, it is always produced as equal amounts of matter and anti-matter - because of various conservation laws to do with charge and all the other properties that particles have.
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You could start here: http://math.ucr.edu/home/baez/einstein/ That gives a reasonable comprehensible explanation of the math and what it means. No. Mass is not the only thing that gives rise to gravity. This is described by the elements of the stress-energy tensor: Mass is included (mainly) as the energy density. It doesn't. They are inextricably linked.
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And, again, this is the problem with trying to understand the geometry of pseudo-Reimannian manifolds by looking at pictures in popular science articles. https://en.wikipedia.org/wiki/Tests_of_general_relativity http://www.thephysicsmill.com/2015/11/28/classical-tests-general-relativity/ http://www.astro.sunysb.edu/rosalba/astro2030/GeneralRelativity_tests.pdf Yes. You may have noticed that apples fall from trees. But he had a very, very deep understanding of the maths behind the theory (he came up with it, after all) and so his intuition was useful. No. Gravitational waves are transient and very, very small (on cosmological scales).
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Except have good evidence that that is the case. I am not sure that those illustrations tell you anything useful about the way GR behaves. I doubt you can extrapolate from those to come up with an explanation of anything. For example, gravity is mainly due to the curvature of the time dimension, not the spatial ones. But you can't see (or even represent) that in those diagrams. If that were the case, there would be no gravity outside of the body. But there is, so your expectation is faulty. (Which is the problem when trying to use your intuition to understand what you think GR should do.) No, but they do carry energy away. So the mass of the resulting neutron star is less than the sum of the two original ones.
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I have never heard it described in those terms before. And I don't see how it could create mass. But you might need someone with a more detailed knowledge of GR than I have. (You need someone like Mordred to join the thread ...)