Can Moduli Fields Parametrize the Cosmological Constant?
Abstract
We study the cosmological evolution of string/M moduli fields T. We use Tduality to fix the potential and show that the superpotential W is a function of the duality invariant function j(T) only. If W is given as a finite polynomial of j then the moduli fields do not give an accelerating universe, i.e. they cannot be used as quintessence. Furthermore, at T >> 1 the potential is given by a double exponential potential V ~= e^{ae√2 T} leading to a fast decaying behavior at large times. For moduli potentials with a finite v.e.v. of T the energy density redshift is model dependent but if T has a finite mass, m < ∞, then the moduli energy density redshifts faster or equal to matter. Only if the moduli mass is infinite can the moduli energy density dominate the universe independently of the initial conditions.
 Publication:

International Journal of Modern Physics D
 Pub Date:
 2002
 DOI:
 10.1142/S0218271802001974
 arXiv:
 arXiv:hepph/9910330
 Bibcode:
 2002IJMPD..11..653D
 Keywords:

 Astrophysics;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 13 pages, LaTeX, 3 postscript figures