The dilaton as a candidate for dark matter
نویسنده
چکیده
We examine consequences of the stabilization of the dilaton through the axion. An estimate of the resulting dilaton potential yields a relation between the axion parameter mafPQ and the average instanton radius, and predicts the ratio between the dilaton mass mφ and the axion mass ma. If we identify the string axion with a Peccei–Quinn axion, thenmφmP l ∼ mafPQ, and the dilaton should be strongly aligned √ 〈φ2〉 ≤ 10−4mP l at the QCD scale, in order not to overclose the universe. Contribution to the Workshop on Aspects of Dark Matter in Astro– and Particle Physics, Heidelberg (Germany) 16–20 September 1996. email: [email protected]–muenchen.de.
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