The fourth tautological group of M g , n and relations with the cohomology
نویسنده
چکیده
We give a complete description of the fourth tautological group of the moduli space of pointed stable curves, Mg,n, and prove that for g ≥ 8 it coincides with the cohomology group with rational coefficients. We further give a conjectural upper bound depending on the genus for the degree of new tautological relations.
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تاریخ انتشار 2000