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Dynamic Space Flow

  1. Dec 25, 2015 #1
    I thought I was following and understanding a lot of ideas about Black Holes until I revisited the concept of Spacetime 'flowing' within the Event Horizon and, assuming a singularity, disappearing.

    Now, The Hawking Radiation can be encoded with the information patterns for MATTER (which is almost undoubtedly evaporated to energy on its way) according to the external observations of the "surface" effected by the Horizon itself - therefore, this information, momentum, mass/energy, and somehow, presumably, angular momentum all of which must be preserved can be.
    HOWEVER,
    What about the on-zero vacuum energies, Dark Energy and Higgs Fields etc. permeating spacetime? Surely these, as energy, must be preserved; but the rate at which spacetime is apparently "flowing" into the singularity exceeds celerity and so HUGE volumes of energetic potential* are ... what?

    Also, where is the spacetime coming from? How can it flow (I appreciate the mathematics involved show this,but cannot reconcile this concept) again, with huge volumes apparently disappearing 'down the plughole' without there being a noticeable "reduction in spacetime" (Yes, I can see this sis something not easily measurable, but I hope you can see my point)
    Certainly DE can be propagating spacetime but, not enough?
     
  2. jcsd
  3. Dec 25, 2015 #2

    Nugatory

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    Staff: Mentor

    The "space flow" is just a metaphor that some people find helpful in visualizing the behavior of a test particle in the neighborhood of a black hole. If it isn't helping you visualize what's going on.... Don't use it.

    The math is the final authority, and it does not say huge volumes of spacetime are being created somewhere and then disappearing down the drain.
     
  4. Dec 27, 2015 #3
    "The math is the final authority, and it does not say huge volumes of spacetime are being created somewhere and then disappearing down the drain."
    Exactly - this is why I have difficulty with the definition given:
    "I prefer a different definition. A black hole is a place where space is falling faster than light."

    I can only assume that the terminology is poor, referring to mass/energy contributions to the field net energies as 'space', rather than space(time) itself when they state "space", such as:

    "The picture of spacing falling into a black hole has a sound mathematical basis" which, interestingly is with reference to Gullstrand-Painlev€ which seems only to, as you mentioned, describe a conversion between interpretations of one distant observer and a local one in vicinity of a BH's Event Horizon.

    http://jila.colorado.edu/~ajsh/insidebh/waterfall.html
     
  5. Dec 27, 2015 #4

    Nugatory

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    Staff: Mentor

    That site is interestingly different from (and in some ways better than) many of the other math-free popular explanations around. There's nothing wrong with good popularizations as long as you're aware of their limitations.

    Here the limitation is that the flow model, with spacetime as a fluid and matter as fish being swept along by the water doesn't work AT ALL as a starting point for thinking about vacuum energy, Hawking radiation, the Higgs field, dark energy and the other stuff you mention in the first post. It is a good way of thinking about the behavior of small masses moving in the vicinity of the black hole; if we limit ourselves to that problem the claim of being supported by G-P coordinates is reasonable.
     
  6. Dec 28, 2015 #5
    Thank you!
     
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