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Big Bang theory 3

  1. Mar 16, 2004 #1
    3) Why did it become unfashionable to mention the centre of the universe after the 16th century, when Copernicus placed the sun near there?
    Every body has a centre of gravity, whether it is a galaxy, a person, or a pebble. The universe had one when it first appeared: What happened to it? What would happen if universal expansion stopped and, subsequently, bodies of mass no longer orbited greater bodies of mass? Would gravity cease to be a force, or would a sequence of universal attraction reunite matter? Where would it reunite? Is the universal centre of mass of no more significance than a theoretical point in space?
    The centre of the universe has four-dimensional coordinates of 0(x),0(y),0(z), and 0(t). This is its point of origin – although the time zero can be misleading, since everything outside it is of today’s age, in one form or another. The fact that we do not have a direct line of sight to the point of origin that is within three hundred thousand years of it, does not negate the fact of its existence. So why do we ignore it? Is it a case of out of sight, out of mind?
    4) Why are we looking for a particle of gravity?
    This is really a continuation of the first question, but it is impossible (so far) to accept that physical law, even that applied through quantum mechanics, treats the force of gravity and the other three forces, equally. Natural law dictated that the force of gravity should break symmetry first.
    At the instant of big bang detonation, there were no photons and no particles of matter: Just energy. Gravity existed at that moment, before particle development. It is easy to understand why particle exchange occurs in electromagnetic and nuclear forces, but not so gravity. Why cannot gravity be a field that causes interaction of matter (and anti-matter), without being of particle composition itself? It should be able to operate through the vacuum of space inflating from its centre.
    Geophysics capitalises on the elastic properties of energy through rocks. Velocities can increase, decrease, and increase again, from a single induction of energy, depending on the composition of the rocks through which the energy travels. Hence we can locate oil – and other substances – far beneath Earth’s surface. The rate of inflation of space could vary as a result of the same phenomenon, for all anybody knows. It is yet to be established that there are no variations in the characteristics of space. Because it appears to have a fairly uniform ‘temperature’ does not mean that all its other characteristics are the same. The big bang featured an induction of energy. It may be premature to decide that space will inflate for ever, just because happens to be doing so at the moment. Eternal inflation is an ugly idea – except to Zeno and other aficionados of physical infinity. Energy passing through all matter – including space – could be of variable velocity. Yet discussion on it is not in evidence.
    5) Why doesn’t cosmological theory follow the sequence of nett gravitational attraction to its logical culmination?
    A pebble is attracted towards the Earth’s centre of mass, and so is the moon. Earth would ‘like’ to nestle at the Sun’s centre of mass. So would the other planets in the solar system. The sun would like to go to the centre of the Milky Way, and would do so were it not in sufficiently high-velocity orbiting motion around it. The Milky Way may head for Andromeda. But to where is all this leading?
    Universal objects are attracted to each other in orderly sequence, according to their mass, and that sequence is indicating a central, universal destination containing the greatest density of mass of all. This trail of attraction is not followed in standard theory. Why not?
    6) Is the centre of the universe at rest?
    This is of course a question from a fool, since it flies in the face of relativity theory. But to ask questions is the point of this essay.
    The centre of a sphere is at rest in relation to any motion of that sphere. The sphere, however, is in motion relative to the motion of all other bodies of mass, and its centre is therefore also in motion relative to other bodies of mass. But only if the universe’s motion were relative to another universe’s motion could its central point be in motion. Our universe is not moving relative to anything external (there is talk of a multi-universe system, but our physical law is not affected by that contradiction in terms). With respect to space and matter in this single universe, therefore, its quantum central point must be at rest. This point should be the universe’s point of origin, and its centre of mass, and its centre of gravity. It will not be in motion.
    This is at odds with the fundamental hypothesis on which Einstein’s theory of Special and General Relativity are based: Namely that no particular object in the universe is at rest with respect to space. It depends what is meant by 'object', but to exclude a point as an object on account of its invisibility to the human eye, would be extremely short-sighted (if the inappropriate pun can be pardoned). Is this point orbiting anything? Is it going anywhere, and in relation to what is it in motion? It can hardly be orbiting - or moving away from - itself, and there is no obvious need for it even to be rotating. Neither is it being swung around by cumulative effects of other centres of gravitation, because it is central to all of them. If it did move, it would no longer be the centre. There seem grounds for suggesting that all universal matter is orbiting, ultimately, the universal centre of gravity: The ultimate black hole.
    The centre of Earth’s mass is in motion relative to the rest of the solar system and the universe, but it is at rest in relation to Earth itself. The centre of the universe’s mass is not in motion relative to anything. It is at absolute rest, while everything else is moving around it. If absolute rest cannot be denied, neither can absolute motion.
    Is not all motion relative to all other motion, but absolute against the absolute rest of the universe’s centre? If this were judged to be so, it would not call for relativity theory to be dismantled. It would only need to be modified, and the result would make the force of gravitation so much easier to understand. Einstein perhaps made the mistake of dismissing the problem of absolute motion by denying its existence.
  2. jcsd
  3. Mar 16, 2004 #2


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    Staff: Mentor

    I'm not sure its necessarily "unfashionable," its just (at best) unnecessary.

    The cosmological microwave background radiation we see provides us with our best picture of the very large scale structure of the universe. And it is very homogenius. It suggests a universe with no edges and therefore no center.
    No, if the universe started with a singularity, it started as a point - a point has no center. And every point in the universe started from the same point.

    So naturally, the next question is: if it has no center and no edge, how can it be expanding (or, what is it expanding into?)? Well, there is an analogy: A polka-dotted balloon. The surface of a polka-dotted balloon is a 2d analogy to 3d space. It has finite surface area just as the universe may have finite space. And as the balloon expands, all the dots get further and further from each other in their 2d universe, yet there is no 2d center to the expansion and no edge.
    I'm not sure what you mean: the two are not directly related to each other (ie, gravity does not require expanson and vice versa).
    The point you reference there is the Big Bang singularity. It is not the center of the universe. I covered it above. And as the Hubble Deep Field photos show, if you look in any direction, you get a view closer to the big bang. How can you look in any direction and see the center? Answer: there is no center.
    Gravitons and photons are not classical particles. Saying "energy" existed just after the BB means photons existed. Gravitons are highly theoretical carriers of gravitational attraction. There is much debate as to their existence, so the best way to prove (or disprove) them is to look for them.
    It very well could be. That question is still quite open.
    That is also an open question, but an answerable one: it depends on the matter/energy density of the universe. Right now, the known density is too low for the universe to stop expanding. There may be matter we can't see ("dark matter") or there may not be.
    Could you be more specific? Give an example of something in cosmological theory that doesn't fit your analogies. Or is this about a center of the universe again?
    Interesting question. You are right of course: given that modern physics rejects the idea of a center, the answer can be pretty much whatever you want it to be. I think you'd find it more helpful to let go of such questions though, as they are immaterial to a discussion of existing physical theories. You have demonstrated a more important understanding: you understand why the question is irrelevant.
    You already acknowledged the flaw in the question itself: so no doubt you already see this conclusion is utterly meaningless.
    Last edited: Mar 16, 2004
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