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The most significant, immediate relic of primordial quantum mechanics?

  1. Jul 28, 2004 #1
    Having arisen from quantum disturbances in the early universe, what phenomenon here and now manifests most prominently in macroscopic physics?
  2. jcsd
  3. Jul 29, 2004 #2
    Gravity, if you consider it a force phenomenon. Did you have something more in mind? Space and matter if you consider them physcial phenomenon. Is there a thee most promenate?
    Last edited: Jul 29, 2004
  4. Jul 29, 2004 #3

    Consider this evidence to be expanded from aboriginal quantal interactions, now observable through a human perspective. Gravity, for instance, does not readily demonstrate its quantum character to our unaided senses.
  5. Jul 29, 2004 #4
    Foton interaction, existed in aboriginal quantal interactions, without them ours senses would sense nothing.
  6. Jul 29, 2004 #5


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    Greene, in his new book Fabric of the Universe says that the cosmic clumpiness of matter is quantum irregularity writ large by inflation, and the density variation of the cosmic backgroung, as measured by WMAP, are exactly matched by predictions of what quantum jitteriness (his word) would look like if expanded by inflation.
  7. Jul 29, 2004 #6
    Rader, Thanks for your patience in helping me define the situation in question. I was thinking of a macroscopic structure or coherent energy, initially a quantum fluctuation that is today directly sensible through process of inflation and/or Hubble expansion.

    My SWAG? The Milky Way. Photon interactions in the early universe were indeed at its genesis more fundamentally than any other visual object I can perceive forthwith.
  8. Jul 29, 2004 #7


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    I'm riding on the WMAP bandwagon along with SelfAdjoint.
  9. Jul 29, 2004 #8


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    Depends how many levels of 'indirect' you are comfortable with. For example, the Milky Way is certainly a result of quantum fluctuations (assuming the concordance model of cosmology continues its run of consistency with the data), but smeared through many collisions, mergers, and baryonic matter collapses.

    For a more direct - local - object, why not pick one of the more stable dwarf galaxies, say Fornax, or Draco? They're likely to still have their dark matter wells essentially intact, and much of the original baryonic matter too (with a small smattering of 'metals', from processed H and He).
  10. Jul 29, 2004 #9
    I agree that the cosmic clumpiness is best appreciated through telescope as WMAP. Nereid comes up with some cool, almost naked eye candidates in our neighborhood, though. I never considered the integrity of dark matter wells to indicate large scale evolution of discreteness!
  11. Jul 30, 2004 #10


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    Good point. Nereid always seems to come up with good ideas. Globular clusters are interesting. By all accounts, they are nearly as old as the universe and often largely undisturbed. The added benefit is they are near enough to observe in a fair amount of detail.
  12. Jul 30, 2004 #11
    I guess taht galaxies originate as fluctuations of the differents fields, not only the electromagnetic, but also can exist galaxies originated by fluctuations of the quark field, others originated by fluctuations of the gluon field, etc. Is there any way to predict what fluctuating particle originated the Milky Way?
    Perhaps the question can be: It's possible to associate the morphology of a galaxy to the particle that originated it?
    I want to put this question in the framework of Loop Quantum Cosmology, where there's no inflaton that can decay into the known particles (though there's still inflation, caused by a different mechanism)
  13. Jul 30, 2004 #12
    Bravo! Much like what I am seeking.
  14. Jul 31, 2004 #13


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    As I understand it, a hot or cold region in the CMBR is some kind of shadow (or the inverse) of some quantum fluctuation much earlier; more specifically, an overdense or underdense region - in terms of mass - of the universe at the time of matter-radiation decoupling. However this fluctuation morphed - grew, changed shape, deepened, whatever – but there is still, in some sense, a one-to-one correspondence between the initial quantum fluctuation and the hot or cold region (this is probably model-dependent though).

    When it comes to ‘now’, the relationship between the cold region at the time of decoupling and a (local) galaxy is weaker – mergers, collisions, and so on may have happened many times; even the supermassive black hole at the centre of a galaxy may be a merged object.

    Morphology of nearby galaxies seems to be determined by their last ~1-5 billion years’ history; the morphology of early galaxies is an interesting subject – IMHO we have only a limited idea of these morphologies. One big question for the next decade or two – certainly to the first five years of the JWST – is the nature of early galaxies: their mass function, M/L ratio, metallicity, nuclei, … and morphology. And how well the many theories of galaxy formation and cosmology are consistent with this massive amount of new data.
  15. Jul 31, 2004 #14


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    JWST is an exciting project - scientific goals and required capabilities are laid out in detail here:

    http://ngst.gsfc.nasa.gov/science/ScienceGoals.htm [Broken]

    Long before that project comes on line, though (2011), we should have some VERY interesting data from the Large Binocular Telescope - link here:


    It seems that the deeper we look into space, the more galaxies we find, and many of those old galaxies are large and very luminous. There may come a transition point at z>? where we find this not to be true, but we have not found that transition "boundary" yet. As matters stand today (if we assume that redshift=cosmological distance) astronomers are currently finding objects that are problematic for the assumed 13.7Gy age of the BB universe, because our heirarchical galaxy formation model does not predict that objects with their masses and luminosities could have formed so early in the life of the universe. I predict that when the LBT comes online (with 10 times the resolution of HST) observers will find even more highly redshifted objects with apparently high mass and luminosities, and cosmologists will have to re-examine the BB theory and/or re-examine what we "know" about redshift.
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