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About decraig

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  1. Just 2 days ago, Jan 8, 2016, the long awaited follow up paper arrived. http://arxiv.org/abs/1601.00921 Hawking, et al, describe a different sort of animal, not a black hole at all, in the sense that a black hole is defined as a region of space from which nothing can escape, not even light. I suggest naming this new object a "Foo' Hole." In case it has escaped notice, Foo' Holes and Black Holes are mutually exclusive theoretical objects. Should Hawking argue his theory on this site will he also be suspended, as I, by a moderator operating far outside his pay grade? Later.
  2. You certainly do have a lot of questions. Can you explain your obsession with taking votes?
  3. I believe you refer to the radial coordinate. But now I don't know what kind of solution to the field equations you might be talking about. Assuming spherical symmetry you want something like this: [math]c^2d \tau ^2 = f(r,t)c^2dt^2 - g(r,t)dx^2 - d \Omega ^2 [/math] What does that look like? It seems to violate Birkhoff's theorem... http://en.wikipedia.org/wiki/Birkhoff's_theorem_(relativity)
  4. If the metric changes with time, it is not the Schwarzschild metric. It would be a different metric. This is the Schwarzschild metric: Notice there are no terms containing 't' in the metric coefficients. A metric coefficient is the stuff in each term standing in front of ct^2, dr^2, dtheta^2 and dphi^2. You seem to have misunderstood. However, it is true that asymmetrical, irrotational matter will approach spherical symmetry under mutual gravitational attraction. This is due to gravitational time dilation where ingoing velocities of particles slow according to an exter
  5. I already explained what's wrong with your referencing. You're doing the same thing as the other guy. You're referenced an article. You did not cite any of its content. Did you get beyond the title? Should you have bothered to read it, you would know that the article addresses experimental evidence that would distinguish between dark clusters and black holes, but not highly condensed matter and black holes. Strange has something better to offer. Of course; there is a distinction. Consider you already have a spherical black hole of mass M, and we throw a small mass, m at it.
  6. I have, many times already. And I just keep on getting false information, red herrings consisting of either irrelevant information of references that even contradict the claim made of them. Look for yourself. As to your second remark that I have put in bold, this is far from correct. Please show me an example where I have done this. Produce this information that is "actually out there". This was the intent of this thread, and no one have yet manged to produced it, yet insist that it is there. If unsupported claims are the stock in trade in this forum, why call it a science forum.
  7. Without the moon, life on earth would be no more complex than bacterium applying accepted theory; the moon reduces the excursion of obliquity (axial tilt). Without the moon the axial tilt could vary as much as 80 degrees. With the moon the obliquity varies from about 22 to 24 degrees over a period of 40K years. However, there is some disagreement. http://io9.com/5829438/earth-doesnt-need-the-moon
  8. Based upon these confused remarks, I don't think physics is your calling. You are not positively contributing to this thread but just trying to win an argument without supplying merit. This repeated invokation of Eddington-Finkelstein coordinates is immaterial. Per canon, mapping to EF coordinates does not affect physical results. The coordinate map between the Schwarzschild and EF charts is invertible over the coordinates range involved. Look it up. EF yields the same time for black hole formation as S. This is introductory level general relativity. If you are versed in elementary general
  9. "My science teacher vaguely defined [energy] as the ability to do work." I don't think this is a very good definition, and says "energy is the ability to do energy". Formally, work has units of energy. In terms of forces, W = Fd. Work is force applied over a distance. It would be better so say that energy has at least two forms, kinetic and potential, and that one form can be become another. --------------------------------------------------- On energy conservation: 1) The energy of a system is not conserved. Energy can enter or escape the system. Rather, we might formu
  10. Doh! Yes, replacing c with bc is the obvious part I missed, such that, if b canels on both sides of a set of equations, then those equations are invariant under rescaling of c.
  11. Thanks, for that. Add electric charge and you get the Reissner-Nordstrom metric, http://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric, with two critical radii. Reissner–Nordström
  12. The title should have been: "Is physics invariant under global regauging of c?" The geometrical constant relating dimensions of time and distance is c=~300,000 km/sec. Are the laws of physics invariant under regauging of c; that is [math]c \leftarrow c' = b c[/math] where b is real scalar? I'm sure there's something obvious I'm missing.
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