Journal of the London Mathematical Society

Table of Contents - 2006 - Volume 74, Issue 03  


Notes and Papers

SINGULARITIES OF ORBIT CLOSURES IN MODULE VARIETIES AND CONES OVER RATIONAL NORMAL CURVES

GRZEGORZ ZWARA a1 1
a1 Faculty of Mathematics and Computer Science, Nicolaus Copernicus University, Chopina 12/18, 87-100 Torun, Poland gzw74ara@mat.uni.torun.pl

Article author query
zwara g   [Google Scholar] 
 

Abstract

Let $N$ be a point of an orbit closure $\overline{{\mathcal O}}_M$ in a module variety such that its orbit ${\mathcal O}_N$ has codimension 2 in $\overline{{\mathcal O}}_M$. We show that under some additional conditions the pointed variety $(\overline{{\mathcal O}}_M,N)$ is smoothly equivalent to a cone over a rational normal curve.

(Published Online January 4 2007)
(Received July 28 2005)
(Revised February 13 2006)

Maths Classification

14L30 (primary); 14B05; 16G10; 16G20 (secondary).

Footnotes

1 The author gratefully acknowledges support from the Polish Scientific Grant KBN No. 1 P03A 018 27.