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The inconsistent current picture of the universe?

  1. Sep 17, 2008 #1
    I can't help noticing some inconsistencies in either the accepted large-scale model of the universe or my understanding of it, so any explanations on the points provided are welcome.

    Point A:
    What are the evidence of the evidence that the universe is expanding?

    The red shifts of distant objects seem to indicate that they are moving away, but is this the only explanation?
    What i come across are several ways to explain universe's expansion - (a) space expands, matter stays same, (b) space expands, matter expands, (c) space expands, matter sticks together staying same with distances expanding.

    What seems inconsistent here:
    (a) Dark matter and dark energy. Stuff that is supposed to pull galaxies together, accounting for many supposed mass deficit anomalies, making up 97% of the mass of the universe. A universe made of intangible undetectable something does not sound consistent.

    (b) Why the light red shifts then? If it expands too, nothing should change, if it does not, it should blue shift.

    (c) Why does all atoms are of the same size then?

    (d) Any (d,...,+inf) points i missed?

    Are there other explanations for red shifts, and how plausible are they?
    (A1) What if the universe is contracting, and the free light does not, producing apparent red shift?
    (A2) What if the universe is contracting, and the light stretches on the in-fall on the higher dimension across which it contracts?
    (A3) What if the universe is a fixed hypersphere, and the red shift is due to the curvature, like horizon on Earth?
    (A4) What if the universe is whatever it is, and the red shift is due to a property of light to red shift due to some kind of "friction" against the "meta medium" of space?

    Point B:
    The origin.
    (B1)Why should there be an origin? (Ok, rhetorical question).
    (B2)Why should the start be at the small beginning, why not at a vast beginning? Taking one of the contraction theories from A, the universe can start as an awfully huge cloud of dust, condensing in whatever stuff we see around now, just like the dust after big bang would have condensed. Any objections to that scheme under given assumptions?
    (B3)It takes a tiny mass of a big star to make a black hole, and it is assumed that nothing can escape black hole's event horizon, then why big bang matter did? All the matter of the universe concentrated at one point sounds like a huge and hot black hole. What is violated up there?

    Point C:
    (C1)What implies that the universe must be symmetric in most if not all terms?
    (C2)Why antimatter is supposed to be in symmetric quantities to matter? Can it not be some kind of anomaly, or a different phenomena entirely?
    (C3)The T-symmetry violation due to entropy. For all i heared about entropy the main, core part of it is that it is statistical, and like any statistical thing, it is not bound to any laws, only patterns, right? Then why the argument about entropy being increasing/decreasing in time reversal thought experiment is used as evidence?
    (C4)Information cannot escape black hole, CPT symmetry violation evidence. I heared, that an event horizon of a black hole extends towards the object about to cross it, is that a real fact/theory prediction/bogosity of the internet? If true, does it mean that information do escape from under event horizon?

    To keep this thread sounding sane, i'll cut the list here.
    As was said above, explanations are welcome...
  2. jcsd
  3. Sep 17, 2008 #2


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    "A universe made of intangible undetectable something does not sound consistent."

    Dark matter interacts with gravity, it just doesn't interact with EM radiation. Other particles exhibit simliar properties, such as neutrinos, but they have been rules out as the culprit.

    Dark energy is really just a name we apply to 'whatever it is that is causing the universe to expand'.

    "Why the light red shifts then? If it expands too, nothing should change...
    Why does all atoms are of the same size then?"

    You seem to be under the impression that 'the universe expanding' means 'everything in it is expanding'. It isn't. It is merely a very, very weak force of some sort that expands space. Anything smaller than a galaxy has enough proximity (and thus, gravitational force) to completely overwhelm this tiny force (which is why atoms, or even planets don't expand). But the gravity between galaxies is so weak, that this force can draw them apart.

    Think of this very loose analogy: gentle ripples on a pond can push two floating leaves apart, causing the cluster of leaves to "expand", but those same gentle ripples don't have any hope whatsoever of tearing the leaves apart. The leaves themelves are simply immune that the vanishly small force acting on them.
  4. Sep 18, 2008 #3
    Invisible and effectively undetectable something, that makes up most of the universe, yet was never directly observed, right?

    So, is there a (1)dimensional expansion, or just matter flying apart under a weak (2)force of dark energy?

    (1) If space itself is expanding, why not the atoms? The light do, the atoms don't, yet they are made of the same thing if quantum physics is right and i got the particle-wave dualism correctly.
    (2) Raises a question, where red shift comes from, as neither of the "dark" substances interacts electromagnetically and so are not supposed to affect light directly, neither their gravity can, as they are assumed evenly spread. And dark energy, that is responsible for actual expansion is said not to be interacting with any fundamental forces, raising a question, how could it stretch light?

    That will be (2), as the waves will appear the same to the leaves, since the relative sizes are the same and motion is statistically constant. The red shift seems lacking in this analogy.
  5. Sep 18, 2008 #4


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    Your knowledge of the subject is a little thin for such speculation. It is important to point out that red shift is not the only reason for thinking that space is expanding. There are other measuring sticks and other theories that point to it. Google "pillars big bang". Or start by reading the Wiki on the subject.
  6. Sep 18, 2008 #5


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    It is quite detectable, just not with EM. Read up on the Bullet Cluster and others.

    Again, the pond analogy: if there is a natural spring in the pond, it will well up and push floating leaves apart. But it sure wouldn't make the leaves exapnd, now would it?

    This spatial expansion is not some wierd super force that creeps into the very interiors of atoms and overrides the giant forces therein, it is simply an expansion of the space between matter. On large scales, the matter is moved apart, on small scales it is too weak.

    You don't have a problem with this concept in the familiar world of matters and gravity: if you did you would be asking: if gravity affects every bit of matter in the universe, then why aren't the-very-atoms-that-my-body-is-made-of squeezed down to nothingness by gravity? Answer: because gravity is easily overcome by electron replusion in molecules.

    Hang on. Who said dark matter was spread evenly? It's not.
  7. Sep 19, 2008 #6
    Atomic matter doesn't expand because its distance scale is determined by the electromagnetic force, e.g.: the ground state orbital of a hydrogen electron is dependent on the electric potential.

    Sean Carroll calls the idea that galaxies (on average) are moving away from each other a 'grammatical error'. This doesn't mean that the univserse isn't expanding. So the red shift is not a result of the relativistic doppler effect, but due to changes in the metric between galaxies.

    DaveC. I'm not sure what you mean by a weak force causing things to expand. Maybe you were trying to put this stuff in simple language.

    I would say that the universe is expanding because that's the way it's shaped. The shape of a spacelike hypersurface will dictate how geodesics evolve over time.
    Last edited: Sep 19, 2008
  8. Sep 20, 2008 #7


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    Here is a reference that expands on Phrak's comment:

    Expanding Space: the Root of all Evil?
    Authors: Matthew J. Francis, Luke A. Barnes, J. Berian James, Geraint F. Lewis
  9. Sep 20, 2008 #8
    Wow. Thanks, atyy. I'll have to read it when I'm awake. I've only had the one source.
  10. Sep 20, 2008 #9
    G'day from the land of ozzzzzz

    What is expanding?

    What observations indicate to us that the universe is expanding?

    They say that the space-time is expanding but ! the actual objects do not show expansion.

    This theory of expansion is provided by the redshift data.

    The more understanding we have of Supernovas the more intinsic qualities of redshift. This has put redshift into question.


    I would rather study the formation of stars and galaxies in their actual images than work on emaginary data.

    Reminds me of the King and the invisible royal dress.
  11. Sep 20, 2008 #10
    The universe is a "4-dimensional pseudo-Riemannian manifold with party supplies."

    -Matthew J. Francis, Luke A. Barnes, J. Berian James, Geraint F. Lewis
  12. Sep 20, 2008 #11
    G'day from the land of ozzzzz

    What party?

    Why wasn't I invited?
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