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Probing the equation of state of the early universe with a space laser interferometer

Naoki Seto·Jun'Ichi Yokoyama
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Abstract

We propose a method to probe the equation of state of the early universe and its evolution, using the stochastic gravitational wave background from inflation. A small deviation from purely radiation dominated universe ($w= 1/3$) would be clearly imprinted on the gravitational wave spectrum $Ω_{GW}(f)$ due to the nearly scale invariant nature of inflationary generated waves.

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Naoki Seto, Jun'Ichi Yokoyama. 2003-05-26. Probing the equation of state of the early universe with a space laser interferometer. https://doi.org/10.1143/jpsj.72.3082

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