THE ACTION OF Sn ON THE COHOMOLOGY OF M0,n(R)
نویسنده
چکیده
In recent work by Etingof, Henriques, Kamnitzer, and the author, a presentation and explicit basis was given for the rational co-homology of the real locus M0,n(R) of the moduli space of stable genus 0 curves with n marked points. We determine the graded character of the action of Sn on this space (induced by permutations of the marked points), both in the form of a plethystic formula for the cycle index, and as an explicit product formula for the value of the character on a given cycle type.
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