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The Missing Baryon Problem & Baryonic Tuller-Fisher

  1. Jun 25, 2010 #1
    I believe people when they read the title of this thread will not understand the nuances of the problem. The fact that 99% of the baryons are missing from satellite dwarf galaxies while most of the baryons are found in clusters may seem insignificant. When you read about this anomaly I would assume you are thinking where did the baryons go and where are they hiding. The point is the baryons should have been part of the initial universe based on the Standard model and should therefore be found in galaxies, dwarf galaxies, and clusters based on formation models for those astronomical objects.

    The mystery deepens as the amount of missing matter changes as if it is control by an unknown parameter in spiral galaxies. I will start a separate thread to discuss Disney et al's paper on spiral galaxies.

    As the properties of a spiral galaxy should be controlled by multiple independent parameters (Initial gas cloud mass and velocity, relative torque of adjacent gas clouds, dark matter cloud concentration, initial spin, merger history and so on.) based on the hierarchical dark matter model, one would not expect the spiral and disk galaxy parameters to be tightly controlled and linked to one another.

    The observational point is the missing baryonic matter is not random but is again tightly controlled. Why?

    In clusters there is more baryonic mass about the galaxies. What is the source of that matter? Why does it not form galaxies? (A basic calculation that is included in my copy of Introduction to Intergalactic Astronomy and Cosmology by Peter Schneider shows that cluster gas should have collapsed to form stars. There are for the cluster gas three puzzles. Why some much more gas, why is the gas so hot, and what keeps the gas from collapsing to form stars.)


    This is a talk by Bergman where he states the puzzle as to why the amount of missing galaxy mass is tightly controlled.

    http://www.sron.nl/files/HEA/XRAY2010/talks/9/bregman.pdf [Broken]

    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jun 26, 2010 #2
    I am not sure people will understand why this observation is interesting.

    The ratio of the BH hole's mass to the ratio of BH hole's Host galaxy get less with redshift by a factor of 7 from z=0 to z=3. Gets less by a factor of 7. Gets less by a factor of 7.

    Either the BH has lost mass which is assumed to be impossible or the galaxies have gained mass or BH mass formation was more efficient at Z=3 than Z=0 in a manner that changes with in a straight line with redshift.

    I am placing this observation in this thread because it concerns an anomaly concerning mass. Specific astronomical objects have more or less gas. Gas is mass.

    This is a public link to the same paper.


    The quasar MBH–Mhost relation through Cosmic Time
    II – Evidence for evolution from z = 3 to the present age

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