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arXiv · hep-th/9308042

On field redefinitions and exact solutions in string theory

A. A. Tseytlin
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Abstract

String backgrounds associated with gauged $G/H$ WZNW models in general depend non-trivially on $α'$. We note, however, that there exists a local covariant $\a'$-dependent field redefinition that relates the exact metric-dilaton background corresponding to the $SL(2,R)/U(1)$ model to its leading-order form ($D=2$ black hole). As a consequence, there exists a `scheme' in which the string effective equations have the latter as an exact solution. However, the corresponding equation for the tachyon (which, like other Weyl anomaly coefficients, has scheme-dependent form) still contains corrections of all orders in $α'$. As a result, the `probes' (the tachyons) still feel the $α'$-corrected background. The field redefinitions we discuss contain the dilaton terms in the metric transformation law. We comment on exact forms of the duality transformation in different `schemes'.

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A. A. Tseytlin. 1993-09-15. On field redefinitions and exact solutions in string theory. https://doi.org/10.1016/0370-2693(93)91372-t

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