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The cosmic microwave background and the hadron era of the early universe: A possible connection
Authors:M Dersarkissian
Institution:Department of Physics, Temple University, Philadelphia, Pa. 19122, USA
Abstract:A cosmological model is constructed which is a Friedman model, but with a finite ultimate temperature (TF). A plausible argument is presented which suggests that the existence of TF and the cosmic microwave background restricts the form of the hadronic level density:
/></figure>, where <em>A</em>, <em>B</em> = constants. In our model, <math><mtext>B = </mtext><mtext>7</mtext><mtext>2</mtext><mtext>?</mtext><mtext>3</mtext><mtext>s</mtext><mtext>, </mtext><mtext>where</mtext><mtext> s = </mtext><mtext>positive</mtext></math> integer. The case <math><mtext>s = 3 (B = </mtext><mtext>5</mtext><mtext>2</mtext><mtext>)</mtext></math> is the well-known Hagedorn model; the Frautschi model corresponds to <em>s</em> = 6 (<em>B</em> = 3); the cases <math><mtext>s = 1 (B = </mtext><mtext>1</mtext><mtext>2</mtext><mtext>)</mtext></math> and <em>s</em> = 2 (<em>B</em> = 2) have not been considered before now. For each value of <math><mtext>B < </mtext><mtext>7</mtext><mtext>2</mtext></math>, the model gives the temperature (<em>T</em><sub><em>γ</em>0</sub>) of the microwave background as a function of <em>A</em>, <em>T</em><sub><em>F</em></sub> and <em>?</em><sub>0</sub> (the present energy density of the universe). Two fascinating results then emerge: first, all estimates of <em>T</em><sub><em>γ</em>0</sub> favor a low density Friedman universe (<em>?</em>0 = 10<sup>?31</sup><em>g</em>/<em>cm</em><sup>3</sup>), which rules out a universe with positive curvature; second, for <em>?</em><sub>0</sub> = 10<sup>?31</sup><em>gr</em>/<em>cm</em><sup>3</sup> the best estimate of <em>T</em><sub><em>γ</em>0</sub> (?3K) occurs for the Hagedorn model.</td>
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