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A Principle to Determine the Number (3 + 1) of Large Spacetime Dimensions

S. Kalyana Rama
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Abstract

We assume that our universe originated from highly excited and interacting strings with coupling constant g_s = {\cal O} (1). Fluctuations of spacetime geometry are large in such strings and the physics dictating the emergence of a final spacetime configuration is not known. We propose that, nevertheless, it is determined by an entropic principle that the final spacetime configuration must have maximum entropy for a given amount of energy. This principle implies, under some assumptions, that the spacetime configuration that emerges finally is a (3 + 1) -- dimensional FRW universe filled with w = 1 perfect fluid and with 6 -- dimensional compact space of size l_s; in particular, the number of large spacetime dimensions is d = 3 + 1. Such an universe may evolve subsequently into our universe, perhaps as in Banks -- Fischler scenario.

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BibTeXRIS

S. Kalyana Rama. 2006-10-18. A Principle to Determine the Number (3 + 1) of Large Spacetime Dimensions. https://doi.org/10.1016/j.physletb.2006.11.077

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