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Comments on D-Instantons in c<1 Strings

Masafumi Fukuma·Shigeaki Yahikozawa
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Abstract

We suggest that the boundary cosmological constant ζin c<1 unitary string theory be regarded as the one-dimensional complex coordinate of the target space on which the boundaries of world-sheets can live. From this viewpoint we explicitly construct analogues of D-instantons which satisfy Polchinski's ``combinatorics of boundaries.'' We further show that our operator formalism developed in the preceding articles is powerful in evaluating D-instanton effects, and also demonstrate for simple cases that these effects exactly coincide with the stringy nonperturbative effects found in the exact solutions of string equations.

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Masafumi Fukuma, Shigeaki Yahikozawa. 1999-06-18. Comments on D-Instantons in c<1 Strings. https://doi.org/10.1016/s0370-2693(99)00744-3

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