Chow Quotients of Grassmannians Ii

نویسنده

  • Sean Keel
چکیده

1.0 Properties of M0,n ⊂ M0,n. (1) M0,n has a natural moduli interpretation, namely it is the moduli space of stable n-pointed rational curves. (2) Given power series f1(z), . . . , fn(z) which we think of as a one parameter family in M0,n one can ask: What is the limiting stable n-pointed rational curve in M0,n as z → 0 ? There is a beautiful answer, due to Kapranov [Kapranov93a], in terms of the Tits tree for PGL2. (3) M0,n ⊂ M0,n has a natural Mori theoretic meaning, namely it is the log canonical model, [KM]. In particular the pair (M0,n, ∂M0,n) has log canonical singularities (a natural generalisation of toroidal).

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تاریخ انتشار 2004