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Revamping general concept and cosmological principle

  1. May 25, 2012 #1

    Why would we assume matter is spread homogeneously throughout the universe if its only 4.6% of universe :confused:

    The universe is believed to be mostly composed of dark energy and dark matter, both of which are poorly understood at present.

    BBT explains about CMBR, redshift, expansion and farther galaxies appear as they are in their infancy... it all goes well with predictions ,but these are only related to 4.6%

    what about the history of dark energy ?it only comes in to question at this time period of bigbang ,inflationary theory was introduced to bolster the original BBT which failed to explain immense distance between galaxies on opposite directions,what do physicist do now to account for dark energy

    I think physicist for instant gratification and mentors here in this forum for the sake of adhering to mainstream ideology give too much conclusiveness for BBT disregarding the fact that it's only tentative

    i think the beginning of universe is best understood by quantum mechanics rather than formulating theory based on redshift ,metric expansion, study of behavior of large scale structures
  2. jcsd
  3. May 30, 2012 #2
    BTW, I hate that chart.

    Because we look at the universe, and the stuff looks homogenous. You point your telescope at one part of the sky, count galaxies and look at spectra. You point your telescope at some other part of the sky, count galaxies and look at spectra. They look the same.

    Except that you run into the problem that quantum effects are at scales much smaller than galaxies.
  4. May 30, 2012 #3
    The human brain is poorly understood as well, but that doesn't mean human brains don't exist.

    What are you saying? The standard cosmology can explain (more or less) every observation made so far. What else can you possibly want?

    People think all kinds of things; a considerable fraction of these things are not true. Show your work or don't bother talking about it at all.
  5. May 30, 2012 #4


    have you heard the story of frog that lives in a well.matter is only small percentage of universe and we inhibit inside that wedge of 4% ,it does not define universe as a whole.we see galaxies count same everywhere we look around us because we are inside somewhere of the clutter of matter.

    we don't get to know the working of clock by studying the movement of clock hands..what powers is the electrons in the battery
  6. May 31, 2012 #5
    i hadn't said universe does not exist

    i want a sensible explanation for the origin of space energy & life based on scientific studies in layman terms without resorting to singularities and unquestionable constants

    answer to a fallacious argument is a better argument not suppression of ideas
    - carl sagan
    Last edited: May 31, 2012
  7. May 31, 2012 #6


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    So what?
    Again, so what? What else would you look at?
    Observational evidence and Einsteins field equations.
    If you believe scientists and PF mentors are blathering idiots who never considered the issues you raise, your grasp of cosmology and the scientific method may be incomplete.
    Current models work just fine in their own regimes, neither QM or GR work at all scales.
  8. May 31, 2012 #7
    i don't think one will see same density of galaxies where ever he go in universe .matter is just clumped in a tiny region of space gradually dispersing into vacuum and somewhere in it is our place, so we see matter all around homogeneously .it is like an atom describing universe from its perspective.

    if physicist are soooo sure that matter is homogeneously distributed on universe they shouldn't have any hesitation admitting universe is closed but they don't...
  9. May 31, 2012 #8
    I was thinking more in the line of dark matter and dark energy are poorly understood, therefore...

    You have to understand, scientists are really doing their best to understand the world. It's not like we're not trying to think of better ways of understanding it, it's that there seem to be none. If you have a better _quantitative_ idea (none of that pseudo-newage mumbo jumbo), then go ahead and make it known.

    An argument would be of the form "I think X, because...". Your statement is not an argument: you just say "I think X". Can you see how this is not helpful at all?
  10. May 31, 2012 #9
    no, it's like an astronomer describing the universe as he sees it

    the way we see it is that, on large scales, the observable universe is isotropic

    that's just how it is. It's what is *seen*, not what we *think is true*, but what actually *is true*
  11. May 31, 2012 #10
    i think matter is not homogeneously distributed ,because

    there's far more SPACE than stars in the night sky.and also inflationary theory says space expanded exponentially ..for homogeneity matter has to be at least in some respectable proportion with amount of space AND matter is just condensed energy or slow vibration HOW could you define THIS GRAND UNIVERSE with this puny stuff called matter , How could you define a human with his mucus.
  12. May 31, 2012 #11
    we the HU-MANS are undermining the vastness of universe ,universe is not built to our imaginary scales.if we could communicate the idea of 1 Lightyear to a bacteria do you think it would have gotten it correctly like us?? it's vastness probably ends with 100 kms (grossly exaggerated)
    we are no different
    a galaxy is a BIG thing for us,but if galaxy has life universe will be congested for it... UNIVERSE GOES beyond anything ever could conceive

    moreover matter is an anomaly created from a singularity , empty space between our fingers and stars is what DEFINES UNIVERSE we have to study that space.a theory based on movement of galaxies and CMB only explains the activity not the origin .and people discourage taking about "what was the state before bigbang??( which i dont believe) saying whatever happened then have no consequence after BB.. it pisses me off
    Last edited: May 31, 2012
  13. May 31, 2012 #12
    currently, the observable universe is the only part of the universe known to exist. It is unknown whether the universe is finite or infinite. From what we can observe, what I said is exactly true. It has been measured, and has a radius of about 45.7 billion light years.

    From what we can observe, we can say nothing of the rest of a hypothetically infinite universe, or the rest of a hypothetically finite universe.
  14. May 31, 2012 #13
    Could you please tell me why physicist refuse to admit universe as a closed sphere?if matter is isotropic we can conclude it with ease universe is a closed sphere .

    we have 3 hypothesis that means no one is sure about what isotropic -ism. on LARGE SCALE
  15. May 31, 2012 #14
    there is no way to prove if the entire universe is a closed sphere or not. The only things we can say are things about stuff we observe.
  16. May 31, 2012 #15
    And I know matter is not homogeneously distributed because I'm here and not there. I don't think there's anyone who thinks matter is homogeneously distributed in the universe. At the very least you'd have quantum fluctuations, even if you choose your initial state to be exactly homogeneous.

    You are missing the relevant question here, which is whether the inhomogeneities are important for the evolution of large scale structure.

  17. May 31, 2012 #16


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    I see your point.
  18. May 31, 2012 #17
    So you know matter is not homogeneously distributed :eek:

    OK NOw im getting The Idea ! The BigBang Theory Is DeliBerately PerPetuated In a Deceptive Way In oRder To Be QuestioneD And Provoke Interest Among Public

    1.Cosmological principle applies ONLY to our horizon 45.7 bly perimeter

    2.Bigbang is only an event happened in the history of universe NOT the Beginning of universe

    3.BangBang does not describe region of space beyond our horizon - space-time could well be quite different out there

    I'm satisfied
  19. May 31, 2012 #18


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    What you want is not possible. First of all we don't know what the ultimate origin of anything is. Our theories describe the way the universe works in terms of models that are heavily involved with mathematics. Without knowing the math behind the theory it is not possible to completely understand what a theory describes. Without knowing the math any explanation is a watered down shadow prone to oversimplification, misinterpretation, and simply not being believed.

    It's obvious that your knowledge of even basic physics, let alone cosmology, is extremely lacking and you are in dire need of a better education if you want to seriously argue anything having to do with physics. Put simply, if you don't believe us, learn the theory. And if you won't do that, go somewhere else because you are wasting everyone's time here, including your own.
  20. May 31, 2012 #19


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    Not on local scales. On the largest scales, as in the scale where galaxy clusters become tiny dots on the map, matter is homogeneously distributed.

    This is probably because your knowledge on the BBT is completely wrong.
    It is believed that it applies everywhere. We can only verify it within our observable universe.
    Neither you nor anyone else knows whether this is true or false.
    This doesn't even make any sense with regards to actual science.
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