Dynamical Gauge Coupling Constants
نویسنده
چکیده
In string theory the coupling parameters are functions of moduli fields. The actual values of the coupling constants are then dynamically determined through the vacuum expextation values of these fields. We review the attempts to connect such theories to low energy effective field theories with realistic gauge coupling constants. This includes a discussion of supersymmetry breakdown, the question of a running dilaton, string threshold calculations and the possibility of string unification. ∗ Lectures given at the 1995 Trieste Summer School in High Energy Physics and Cosmology, Trieste, Italy, June 1995.
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