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Question regarding pre-bigbang detection.

  1. Jul 5, 2010 #1

    I'm not a physicist although I've studied it to first year degree level in the UK many many years ago. I was just reading an article today on the BBC about a new image that's been captured of the visible universe.

    The following quote got me thinking and I wondered if your expert knowledge may be able to answer a question for me.

    "The CMB is the "first light". It is the light that was finally allowed to move out across space once a post-Big-Bang Universe had cooled sufficiently to permit the formation of hydrogen atoms.

    Before that time, scientists say, the cosmos would have been so hot that matter and radiation would have been "coupled" - the Universe would have been opaque."


    It begs the question has anyone tried to capture some sort of image of this coupling? I know it sounds like a crazy suggestion. Can a sort of matter image can be constructed in some way, might any such theoretical particles be detectable? I mean matter is energy (De Broglie particle waves etc). The Universe may be opaque but only to light. Apologies as my knowledge of physics is absolutely terrible at the moment. It's been about 20 years since I studied anything and I didn't go beyond special relativity and newtonian mechanics.
    Last edited: Jul 5, 2010
  2. jcsd
  3. Jul 5, 2010 #2


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    Photons could not escape from the early universe because it was too dense. It took about 400,000 years for it to dilute sufficiently to become transparent to photons. This, of course, was not an issue for neutrinos.They were able to penetrate the fog shortly after the big bang. Constructing a neutrino telescope is, however, a formidable challenge. Gravity was also able to penetrate the primordial soup. Efforts to detect primordial gravity waves is an active [and more feasible] area of interest in modern astrophysics.
  4. Jul 5, 2010 #3
    If gravity and neutrinos are able to penetrate the early universe, surely this implies that the current universe is a lot bigger than that which is visible? A lot bigger. And this perhaps could be estimated by the rate of propogation of gravity waves as compared to light multiplied by the number of years.
  5. Jul 6, 2010 #4


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    Yes, our universe is a lot bigger than just the visible part. If we ever get to the point where we can directly detect primordial gravitational waves, for instance, we will have a window into a vastly larger region of the universe.
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