On the $\overline {\mu }$--invariant of rational surface singularities

نویسندگان

چکیده

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Kawachi’s Invariant for Normal Surface Singularities

We study a useful numerical invariant of normal surface singularities, introduced recently by T. Kawachi. Using this invariant, we give a quick proof of the (well-known) fact that all log-canonical surface singularities are either elliptic Gorenstein or rational (without assuming a priori that they are Q -Gorenstein). In §2 we prove effective results (stated in terms of Kawachi’s invariant) reg...

متن کامل

The mu-basis and implicitization of a rational parametric surface

The concept of a μ-basis was introduced in the case of parametrized curves in 1998 and generalized to the case of rational ruled surfaces in 2001. The μ-basis can be used to recover the parametric equation as well as to derive the implicit equation of a rational curve or surface. Furthermore, it can be used for surface reparametrization and computation of singular points. In this paper, we gene...

متن کامل

The mu-basis of a rational ruled surface

The mu-basis of a planar rational curve is a polynomial ideal basis comprised of two polynomials that greatly facilitates computing the implicit equation of the curve. This paper defines a mu-basis for a rational ruled surface, and presents a simple algorithm for computing the mu-basis. The mu-basis consists of two polynomials p(x, y, z, s) and q(x, y, z, s) that are linear in x, y, z and degre...

متن کامل

Revisiting the [mu]-basis of a rational ruled surface

The μ-basis of a rational ruled surface P(s, t) = P0(s)+tP1(s) is defined in Chen et al. (Comput. Aided Geom. Design 18 (2001) 61) to consist of two polynomials p(x, y, z, s) and q(x, y, z, s) that are linear in x, y, z. It is shown there that the resultant of p and q with respect to s gives the implicit equation of the rational ruled surface; however, the parametric equation P(s, t) of the rat...

متن کامل

The Poincaré Duality of a Surface with Rational Singularities

In this article, we proof the Poincaré duality with coefficient Ql on a surface with isolated rational singularities. INTRODUCTION The Poincaré duality theorem in the étale cohomology was established in [1, XVIII, 3.2] on the smooth varieties. But in many times, the duality on singular varieties has to be considered. In this paper, we study the surfaces with at most isolated rational singularit...

متن کامل

ذخیره 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: Proceedings of the American Mathematical Society

سال: 2008

ISSN: 0002-9939

DOI: 10.1090/s0002-9939-08-09439-2