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How much matter goes into making black holes?

  1. Jan 9, 2015 #1
    I recently viewed a video with Richard Carrier, who apparently was using information he derived from Lee Smolin. He said that 99.9999% of the matter in the universe goes to making black holes. Is this true? What percentage of matter does go to the making of black holes, is it even something we can calculate and know?
     
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  3. Jan 9, 2015 #2

    Doug Huffman

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    At the heart of Smolin's arguments is the issue of Popper falsifiability. The question should not be "Is this true?", but should be can this be falsified, can it be false? Further, he argues that mathematical calculation is not a reliable guide to truth.
     
  4. Jan 9, 2015 #3

    bapowell

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    Theories (general, universal statements of physical law) must be falsified a la Popper, but particular facts like "99.9999% of the matter in the universe goes to making black holes" can certainly be verified for truth.
     
  5. Jan 9, 2015 #4
    Is is true that the percentage of matter in the universe that goes to making black holes is 99.9999% or greater?
     
  6. Jan 9, 2015 #5
    I am only guessing here, but I presume that what the clever sirs are attempting to say is. Yes, but only on the paper, please correct me if I am wrong.
    one of the possible arguments against this statement "black holes amount of matter = 99.999999% of matter in the universe" is that we are capable of observing black holes with telescopes, we observe them through watching the orbits of stars around black holes.

    http://www.ted.com/talks/andrea_ghez_the_hunt_for_a_supermassive_black_hole
    mighty fine explanation of the hunt for black holes, what they are and such.
     
  7. Jan 9, 2015 #6

    mathman

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  8. Jan 9, 2015 #7

    Chronos

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    Stars convert mass into photons over their lifetimes. The hydrogen fusion process converts about 0.7% of the mass involved into photons in a typical [sun-like] star. The amount of mass available for fusion in such a star is about 0.1 solar masses, so we can conclude that about 0.07% of the total mass is converted to photons over the lifetime of a typical sun-like star. This, however, fails to account for mass-energy conversion in the infant universe, which produced the CMB photons. The baryon asymmetry of the infant universe is estimated at about 1 part in 10 billion. Since matter-antimatter energy conversion is virtually 100% efficient, the matter that survived to become stars was only a microscopic fraction of the initial mass budget of the universe. While black holes may recover 99.9999% of all matter that remains after mass-energy conversion processes have ended in the universe, I doubt they will recover 99.9999% of all photons emitted over the history of the universe.
     
  9. Jan 10, 2015 #8
    When you say "recover" are you essentially meaning the matter swallowed by black holes. It also appears you're suggesting that when the universe reaches heat-death the black holes in the universe at that time will have swallowed/recovered 99.9999% of the remaining matter remaining from the mass-energy conversion processes. I am more interested in the universe in its present state. How much matter in the universe up until now has gone into making black holes?
     
  10. Jan 10, 2015 #9

    Chronos

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    The best guess at present is black holes constitute about 0.0011% of the mass of the universe - re: http://www.universetoday.com/112500/how-much-of-the-universe-is-black-holes/. Note that his is just a guess. Putting a number to the collective mass of black holes in the universe is not an easy task. We can somewhat safely say that individual black holes are not wildly abundant because gravitational lensing events are not evident all across the sky.
     
  11. Jan 10, 2015 #10

    Doug Huffman

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    Quite coincidentally I noticed this thread while napping through
    Apparently Juan Maldecena is in the audience.
     
    Last edited: Jan 10, 2015
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