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What is Hot and Cold?

  1. May 12, 2004 #1
    If scientists understand hot and cold completely then high temperature superconductivity will become a reality and cold fusion is just child play.

    Until then, we can do all the theorizing we want but to really understand the universe we must understand what is hotness and what is coldness.

    The interiors of the stars is extremely hot. The vacuum is extremely cold. And yet they coexist in such discrete boundary. While human beings can be kept alive at merely 98.6 degrees. A few degrees (+/-) deviation will cause almost instant death.
  2. jcsd
  3. May 12, 2004 #2
    Pure coldness is 100% potential energy. Pure hotness is 100% kinetic energy. Most things are just in between.

    If temperatures are used to represent hot and cold. Can the temperatures of two objects be added? Be subtracted? The truth is temperatures of two systems cannot be added but can be subtracted only when the system is combined into a new system.
    Last edited: May 12, 2004
  4. May 12, 2004 #3
    Pure hotness can represents one kind of mass called kinetic mass. Pure coldness is another kind of mass called potential mass. So it can be said that the big bang singularity was made of pure kinetic mass because its temperature is infinite. But the singularity has no motion hence is also made of pure potential mass (temperature is zero from the kinetic theory of heat). It is this contradiction that makes the singularity undefinable.
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