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Big bang and singularity

  1. Jul 20, 2004 #1
    Newton's law of gravity Force = Gm1 m2 / r^2, can be used to calculate the force that the universe as a whole exerts on a particle at its surface, provided a particle on the surface of a sphere containing the entire mass of the universe has a radius greater than 10^ 25 metres (it is currently 10^26 metres).Otherwise general relativity has to be used to calculate " force."
    If the universe continues to expand, Newton's law will remain valid for such a calculation of the force of gravity in our universe.Are there any laws which lose their validity completely as time passes in the universe?
    Last edited: Jul 20, 2004
  2. jcsd
  3. Jul 20, 2004 #2
    That's bull honkie. The Universe is NOT expanding.
  4. Jul 20, 2004 #3
    Maybe when time "passes", since QM is a measurable phenomena where position and momentum are its complementary properties, we can conclude that time itself is under the laws of Heisenberg uncertainty principle, which is deeply connected to h plank constant.

    Maybe Heisenberg uncertainty principle becomes the main law which breaks down all other laws, and in this state, new universes can be created, with different initial conditions, which implies new laws.
    Last edited: Jul 20, 2004
  5. Jul 21, 2004 #4


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    What is your reasoning behind this statement?
    Do you have an alternative interpretation of redshift?
  6. Jul 21, 2004 #5
    WTF?! not only has it been found that the universe is expanding, but it is accelerating OUTWARD! Proove an explanation for that and a nobel prize is yours.

    anyway...back to the thread. I have no idea about what the expanding univers would have on newtonian physics.
  7. Jul 21, 2004 #6
    Actually I do. Gravitational redshift could make things look redder that they really are and therefore make them look like they are moving away. Just speculation though.
  8. Jul 21, 2004 #7
    i dont want to debunk your explanation before you give one....how could gravity cause a change in the frequency of light coming from all directions of the universe.
  9. Jul 21, 2004 #8
    umm....i dont think so...the universe is accelerating, which has been proven by using type 1 supernovas i believe. The point is...Urtalkinstupid, u are in no possition to say the universe isnt expanding. Especially after your theory of gravity (no offense), i really dont think you should ever talk again.
  10. Jul 22, 2004 #9
    Nothing is "proven" in physics. Physics is all theorized. OMG, Entropy I can actually relate to what you said. A bond seems to have formed. Gravity (whether it be my theory or pull) can cause redshift on light. It slows the light down but to compensate for the loss in speed, the light has to change its frequency. ArmoSkater87, my theory is perfectly valid. When people tell me neutrinos have no rest mass, that tells me that you have no reason to say that my theory is disproven.

    So, anyways, the universe is not expanding. What is seen as redshift is just an affect that is slowing down light making it change frequencies. So, is the nobel prize mine yet? We live in a static universe.
  11. Jul 22, 2004 #10
    Hi urtalkinstupid,

    What is the reason that light is slowing down around us almost simultaneously in all directions?

    You have to understand that the chance to find such synchronization among astronomical distances, is millions times less then the Doppler Effect explanation of the expanding universe.
    Last edited: Jul 22, 2004
  12. Jul 22, 2004 #11


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    Besides that, you also have to find the mass thats causing all of this gravitational redshift - that's an enormous amount of mass.

    Also, you have to show how a universe that isn't precisely homogenous could be static. The slightest purturbation would cause local collapses and expansions. Our local group of galaxies, for example, should be rapidly collapsing, but it isn't.
    Last edited: Jul 22, 2004
  13. Jul 22, 2004 #12


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    Pretty easy to test this idea - just look at objects with known masses and see whether there is a relationship between their mass and any observed redshift. GR predicts there is just such a relationship, and observations match the GR predictions.

    At a cosmological scale, there is the (integrated) Sachs-Wolfe effect, some evidence of which should be seen once the full set of WMAP data is analysed (and if not, then I guess we'll have to wait for Planck data). Being generous then, urtalkinstupid 0, GR cosmology 1.5
  14. Jul 22, 2004 #13
    I think, we are back to the omega problem. Omega equals to 1? Greater than 1? Less than 1? Whoever convincingly finds the true value of omega will definitely be awarded the Nobel Prize.
    Last edited: Jul 22, 2004
  15. Jul 22, 2004 #14
    Expanding Universe

    When you say the universe is expanding, be sure to recognize that the universe refers to what we are able to "see" and/or "measure" (whatever the method).
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