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``N=4: A Unifying Framework for 2d Topological Gravity, $c_M\leq 1$ String Theory and Constrained Topological Sigma Model''

Pablo M. Llatas·Shibaji Roy·Jose M. Sanchez de Santos
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Abstract

It is shown that two dimensional (2d) topological gravity in the conformal gauge has a larger symmetry than has been hitherto recognized; in the formulation of Labastida, Pernici and Witten it contains a twisted ``small'' N=4 superconformal symmetry. There are in fact two distinct twisted N=2 structures within this N=4, one of which is shown to be isomorphic to the algebra discussed by the Verlindes and the other corresponds, through bosonization, to $c_M\leq 1$ string theory discussed by Bershadsky et.al. As a byproduct, we find a twisted N=4 structure in $c_M\leq 1$ string theory. We also study the ``mirror'' of this twisted N=4 algebra and find that it corresponds, through another bosonization, to a constrained topological sigma model in complex dimension one.

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Pablo M. Llatas, Shibaji Roy, Jose M. Sanchez de Santos. 1995-02-15. ``N=4: A Unifying Framework for 2d Topological Gravity, $c_M\leq 1$ String Theory and Constrained Topological Sigma Model''. https://doi.org/10.1016/0370-2693(95)00483-2

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