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Gravity Waves and Graceful Exit

  1. Aug 28, 2014 #1
    Recently reading the Scientific American article The Black Hole at the Beginning of Time, which at first glance made me wonder if they were bowing to pressure to increase circulation, did however get me to thinking about Inflation and Graceful Exit, a rather major problem.

    I understand that Stephen Hawking and Werner Israel postulate that the limits on our ability to measure wavelengths is roughly from 10^-7 to 10^11 Hz. I'm pretty sure I can see why those are presently limitations on our ability to measure, but is there any known reason that much larger wavelengths can not exist? say, 10^-18?

    Further then, is it impossible, that oscillating epochs might exist based on extremely long (to us) wave periods?
  2. jcsd
  3. Aug 28, 2014 #2


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    Staff: Mentor

    What is an "oscillating epoch"?
  4. Aug 29, 2014 #3
    1 oscillation per year is 3x10-8 Hz

    1 oscillation per 13.8B years is 2.3x10-18Hz!

    I wonder what the period is for a cyclic universe?
    Last edited: Aug 29, 2014
  5. Aug 29, 2014 #4
    Perhaps a bad choice of words to describe cyclic events like seasons on Earth, but I had hoped to keep it separate. at least in my own mind, from cycles driven by roughly circular motion as in the Earth around the Sun and our solar system around the galactic center. However thinking about a Galactic Year for Sol System only reinforces my curiosity about cyclical events on VERY large time scales.

    It seemed to me the first step is to determine any limits on wavelength. For one thing it might possibly explain or at least open avenues of inquiry on Gravity and/or Dark Energy.
  6. Aug 29, 2014 #5
    Thanks. Although those numbers are easily calculated it does help to just see some examples of the frames about which we are speaking. However I am not chasing ideas about the Bang/Rip question.

    My wandering/wondering has more to do with what we can possibly measure given that the entirety of human existence from just about any point in Evolution you would choose to call even remotely human, isn't even a sizable fraction of a Galactic Year.

    Some of what has fueled this line of thinking is noting that while we can't measure less than a Planck unit, apparently we can deduce beyond Planck if I understand the ESA's data showing that the Universe is not grainy to orders of magnitude beyond Planck.

    The SA article states that if Big Bang is on some larger scale, a 3 Dimensional manifestation of a 4 Dimensional event, we may be able to gather some data about the Parent. Even though we can't employ light for obvious reasons, it may be possible to employ Gravity.

    Obviously all of this as we get closer to The Singularity is highly speculative at this point. I'd just like to establish some reasonable boundaries on my imagination and see where that leads.
  7. Aug 29, 2014 #6
    While, as mentioned in my first post in this thread, Hawking and Israel have postulated the window of limitation on what we can measure at 10^-7 to 10^11, what is the window of what we have actually measured so far?
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