New Instanton Effects in String Theory
نویسنده
چکیده
An important non-perturbative feature of string theory or M -theory compactifications which preserve only N = 1 supersymmetry in four dimensions is that fundamental string worldsheet or brane instantons can sometimes generate an effective superpotential for the light chiral superfields that describe the classical moduli of the background. Such a superpotential drastically alters the low-energy behavior of the theory, since some or all of the branches of the classical moduli space can be lifted.
منابع مشابه
DEVELOPMENT IN STRING THEORY
The string theory is a fast moving subject, both physics wise and in the respect of mathematics. In order to keep up with the discipline it is important to move with new ideas which are being stressed. Here I wish to give extracts from new papers of ideas which I have recently found interesting. There are six papers which are involved: I ."Strings formulated directly in 4 dimensions " A. N...
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