# The cohomology ring of the real locus of the moduli space of stable curves of genus 0 with marked points

@article{Etingof2005TheCR, title={The cohomology ring of the real locus of the moduli space of stable curves of genus 0 with marked points}, author={Pavel Etingof and Andr'e G. Henriques and Joel Kamnitzer and Eric M. Rains}, journal={Annals of Mathematics}, year={2005}, volume={171}, pages={731-777} }

We compute the Poincare polynomial and the cohomology algebra with rational coefficients of the manifold M_n of real points of the moduli space of algebraic curves of genus 0 with n labeled points. This cohomology is a quadratic algebra, and we conjecture that it is Koszul. We also compute the 2-local torsion in the cohomology of M_n. As was shown by the fourth author, the cohomology of M_n does not have odd torsion, so that the above determines the additive structure of the integral homology…

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