Non-rational centers of log canonical singularities
نویسندگان
چکیده
منابع مشابه
0 Log - Canonical Forms and Log Canonical Singularities
For a normal subvariety V of C with a good C∗-action we give a simple characterization for when it has only log canonical, log terminal or rational singularities. Moreover we are able to give formulas for the plurigenera of isolated singular points of such varieties and of the logarithmic Kodaira dimension of V \{0}. For this purpose we introduce sheaves of m-canonical and L2,m-canonical forms ...
متن کاملThe Indices of Log Canonical Singularities
Let (P 2 X; ) be a three dimensional log canonical pair such that has only standard coe cients and P is a center of log canonical singularities for (X; ). Then we get an e ective bound of the indices of these pairs and actually determine all the possible indices. Furthermore, under certain assumptions including the log Minimal Model Program, an e ective bound is also obtained in dimension n 4.
متن کاملRational , Log Canonical , Du Bois Singularities : On the Conjectures of Kollár and Steenbrink ?
Let X be a proper complex variety with Du Bois singularities. Then Hi(X,C) → H(X,OX) is surjective for all i. This property makes this class of singularities behave well with regard to Kodaira type vanishing theorems. Steenbrink conjectured that rational singularities are Du Bois and Kollár conjectured that log canonical singularities are Du Bois. Kollár also conjectured that under some reasona...
متن کاملLog Canonical Singularities and Complete Moduli of Stable Pairs
0.1. This paper consists of two parts. In the first part, assuming the log Minimal Model Program (which is currently only known to be true in dim ≤ 3), we construct the complete moduli of “stable pairs” (X,B) of projective schemes with divisors that generalize the moduli space of n-pointed stable curves Mg,n to arbitrary dimension. The construction itself is a direct generalization of that of [...
متن کاملCanonical Big Cohen-macaulay Algebras and Rational Singularities
We give a canonical construction of a balanced big Cohen-Macaulay algebra for a domain of finite type over C by taking ultraproducts of absolute integral closures in positive characteristic. This yields a new tight closure characterization of rational singularities in characteristic zero.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2012
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2012.06.015