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Self oscillation

  1. Jun 9, 2005 #1


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    One has to provide an input to start an oscillation, but that input can be
    removed and the oscillation will continue.
    So when we talk about space time, if the original, "input", is no longer
    present we are looking at an effect and have to guess the cause.
    So could we work backwards, looking at all the various oscillations in the
    universe, and by elimination find the prime oscillation?
  2. jcsd
  3. Jun 9, 2005 #2


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    Personally I can't say to this more than you already must have thought about.
    the shaking in the spacetime geometry (called gravity waves) has not been felt yet, presumably it is there but the intruments so far are not sensitive enough.

    the shaking in the electromagnetic field represented by the microwave background (which is also very ancient and can be studied to learn about the beginning) is a good comparison to make, by way of analogy:

    people had radio receivers for some 50 years before they detected the CMB
    now they have been detecting the CMB for another 50 years and are still learning from it.

    whatever other kinds of vibration, or particles flying around, they all contain "echos of the big bang", but mostly instruments cannot yet pick it up-----for instance the neutrino detectors can detect neutrinos from the sun and from supernovas but they are not yet sensitive enough to detect the neutrinos made in the first second of time after expansion began.

    maybe, rather than hear or feel gravity waves, we have to "see" the ancient ripples in how matter is clumped and clustered. perhaps things have expanded so much that the wavelengths of important oscillations are so long that we have to look for their imprint in the distribution of galaxies----or in the hot/cold spots of the CMB

    the idea of being in a room and studying the echos, and reconstructing from the echos what made the first noise----that is a good idea. it could be an emblem for all cosmology observations (whether based on old light or old particles or whatever kind of old vibrations people can eventually pick up)

    but you know the current boundaries of research, from your reading, and know how hard it is to detect and decode those old signals
  4. Jun 9, 2005 #3


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    Thanks Marcus, you have given me some new ideas.
  5. Jun 9, 2005 #4


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    the first signal must have been gravity, and that must be a very long wavelengh
    thousands of LYs, so how is it related to the microscopic?
  6. Jun 10, 2005 #5
    Hi Wolram

    If time is like space, as in "spacetime", what is motion? Our notion of change is based upon the perception of time apart from space. Objects in space change position as you follow them through time. What happened to the space they were in a moment ago? Where, right now, is the space they will occupy a moment hence?

    I ask these questions to try to highlight a property of spacetime. It does not change. All spacetime events in this sense are coexistant, eternal. Where does spacetime begin? Where does it end? If you give up your notions of objects traversing space through time and enter into the notion of spacetime as a single universal object, the questions become meaningless.

    Be well,

  7. Jun 10, 2005 #6


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    Hi Nightcleaner.
    I have always though "spacetime", a rather ambiguous term, i think of space
    as an entity, and time as a measure.
    I also think of space as eternal, and matter as a transient, "something that
    pops into existence when the cosmic forces contrive to not equal 0",
    It is said that a perfect vacuum is an impossibility, but i think that "space"
    can achieve this, by absorbing the negative and positive thus returning to
    0. once it has done this the energy, matter will re emerge in a recreation.
    So space is two and the same 1 and-1, but known laws will not allow it
    to keep it neutrality everywhere all the time.
  8. Jun 10, 2005 #7


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    there is just so much conjecture about our beginings, so how can one sift the
    wheat from the chaff, well if you want to believe in the BB fair enough, but
    this pardigram throws up more questions than answers, if you ask a basic
    question, you get a ansewer like nightcleaners, i hate to say this but questions
    like this are beyond present day science, and are an oppinion nothing more.
    The only evidence we have about cosmology comes from EM radiation, as we
    are part of that, we may as well be a fish in in ocean trying to explain its
    enviroment through the vibrations it feels, but are we so senseless? i think
    not, it is human curriosity that will solve this enigma, if not we will perish
    through our ignorance.
  9. Jun 10, 2005 #8
    first oscillation? that's the origin of motion- of change- of time-like dimensions in the phase-space- might as well ask 'why does Existence exist?'- always a rhetorical question-

    'Things can be-
    and their Being is grounded
    in Nothing's ability to noth'

    -kenneth burke

    id est: inability-
  10. Jun 11, 2005 #9


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    May be, but i think string theorist have come up with a before the BB theory.
    And may be the homogonies and isotropic, bounded but infinite, dark energy,
    graviton, higgs boson, axion, people will move in another direction one day.
    i think that day is not far away, when no gravitational radiation or frame
    dragging can be found? or dark matter is falsified? there are so many tests
    that can, will send us back to the drawing board.
    i hope it will not just be a redrafting, but whole new design.
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