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Thoughts on Tachyon Cosmology

G. W. Gibbons
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Abstract

After a pedagogical review of elementary cosmology, I go on to discuss some obstacles to obtaining inflationary or accelerating universes in M/String Theory. In particular, I give an account of an old No-Go Theorem to this effect. I then describe some recent ideas about the possible rôle of the tachyon in cosmology. I stress that there are many objections to a naive inflationary model based on the tachyon, but there remains the possiblity that the tachyon was important in a possible pre-inflationary Open-String Era preceding our present Closed String Era.

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G. W. Gibbons. 2003-01-16. Thoughts on Tachyon Cosmology. https://doi.org/10.1088/0264-9381%2F20%2F12%2F301

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