Anonymous asked in Science & MathematicsPhysics · 1 decade ago

Do we really live in an expanding universe?

Since there appears to be evidence of multiple "black holes, isn't it possible that we live in a dynamic universe with both expansion and contraction. Perhaps more than one 'bang.' After all, might something like a black hole be necessary to create that ultracompact unity that then expanded into our "universe?"

10 Answers

  • 1 decade ago
    Favorite Answer

    Per the "current" Big Bang Theory, the universe is not an explosion of matter moving outward to fill an empty universe; what is expanding is space itself. It is this expansion that causes the physical distance between two co-moving points to increase. Objects that are bound together (such as atoms, people, stars, the solar system, galaxies or your dog) do not expand with spacetime's expansion because the forces that bind them together are strong compared with the Hubble law of expansion that is pulling them apart. Hubble's law is an explanation that states the universe is uniformly expanding everywhere as a unique property of spacetime. This type of universal expansion was developed mathematically in the context of general relativity by Edwin Hubble and Milton Humason in 1929.

  • 1 decade ago

    On a large scale, the universe is expanding. This is well established and measured. On a local scale there is contraction, mainly by the death of stars forming neutron stars and black holes.

    We can only speak for the 'visible universe', which is all points in space-time close enough for their light to reach us. We just assume whatever is beyond that is the same in nature as what is within.

    When the train reaches the station, its dense mass of bodies experiences a 'big bang' when the doors open, and the mass expands over the neighborhood. Some of the mass immediately contracts again at the Starbucks across the street.

    I know of no evidence that black holes will ever 'bang'. The also differ in character from what is considered to be the initial mass concentration of the big bang.

  • 1 decade ago

    Currently we are fairly certain that the universe is expanding. We are not sure really how big the universe actually is, as we can only see about 12-15 billion lightyears in any direction, or if it will contract. There are a number of ideas about the future of the universe (expansion to infinity, expansion than contraction back to nothing, oscillating universe) but I don't think there is any real scientific consensus yet.

  • 1 decade ago

    Please read Stephen Hawkings book "A Brief History of Time", it explains all about our expanding universe, and black holes. The universe is expanding, and black holes are caused by certain types of collapsing stars. So, yes, there is expansion and contraction going on.

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  • 4 years ago

    A singularity... i'm confident you're familar with the freidman equations? -3D^2a/dt^2 = 4*pi*G (p + 3P/c^2)a three(da)^2/dt = 8*pi*Gpa^2 - 3kc^2 See the way it factors to a singularity? If the p is constructive (because it observably is), the finished accurate component to the first equation is. accurate? And length has a accurate away adverse correlation with acceleration... so the bigger the universe receives, the slower the acceleration... which inversly means that on the start the accleration has to were huge (vast bang) and on the grounds that the a (length of the universe) techniques 0, the p (density of remember) will attain infinity. accurate? (0 length= countless density) = singularity And even as it begins increasing it begins of quickly, and slows down because it progresses. *shrug* Or were you searching for some thing more advantageous precise? i'm not somewhat confident what you're asking right here, the phraseology is slightly ambigious. ought to you somewhat i bypass into m concept? i ought to ought to search for the notes, the basics replaced into the in elementary words element I had reachable :)

  • 1 decade ago

    I guess we are living in an expanding universe, with the "Big Bang Theory" confirmed. (This year's Nobel for physics). Try the site below for some fascinating info on this.

  • Anonymous
    1 decade ago

    If the universe is expanding, then everything in it would also be expanding. The problem is showing that this expansion takes place when the 'ruler' expands with it...

  • 1 decade ago

    Universe is expanding and contracting on an alternate basis.

  • 1 decade ago

    It must be expanding... to keep up with my waistline... I still got it.... Sorry... I don't have a clue....

  • 1 decade ago

    to late to think about such things

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