ALUFFI TORSION-FREE IDEALS

A class of algebras which are intermediate between the symmetric and the Rees algebras of an ideal was introduced to define characteristic cycle of a hypersurface parallel to conormal cycle in intersection theory. These algebras are named Aluffi algebras. For a pair of ideals J µ I of a commutative ring R, the Aluffi algebra of I=J is called Aluffi torsion-free if it is isomorphic to the Rees algebra of I=J. In this talk, ideals generated by 2-minors of a 2£n matrix of linear forms and also edge ideals of graphs are considered and some conditions are presented which are equivalent to Aluffi torsion-free property of them.