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Is the String Coupling Constant invariant under T-duality?

Enrique Alvarez·Yuri Kubyshin
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Abstract

It is well known that under T-duality the sigma model dilaton (which is normally thought to be related to the string coupling constant through the simple formula $κ= exp <ϕ>$), undergoes an additive shift. On the other hand, Kugo and Zwiebach, using a simplified form of string field theory, claim that the string coupling constant does not change under the T-duality. Obviously, what seems to happen is that two different coupling constants, associated to different dilatons, are used. In this contribution we shall try to clarify this, and related issues.

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Enrique Alvarez, Yuri Kubyshin. 1996-10-07. Is the String Coupling Constant invariant under T-duality?. https://doi.org/10.1016/s0920-5632(97)00352-6

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