4 papers · 1 filter
Some non-principal rigid ideals in Gorenstein domains of dimension one
Lars Winther Christensen, Alex Gerko, Srikanth B. Iyengar
We discuss an example of a rigid non-principal ideal in a one dimensional (commutative) Gorenstein domain, which contradicts a conjecture of C. Huneke and R. Wiegand. The construct…
Non-existence of Ulrich modules over Cohen-Macaulay local rings
Srikanth B. Iyengar, Linquan Ma, Mark E. Walker +1
Over a Cohen-Macaulay local ring, the minimal number of generators of a maximal Cohen-Macaulay module is bounded above by its multiplicity. In 1984 Ulrich asked whether there alway…
A freeness criterion for complexes with derived actions
Sylvain Brochard, Srikanth B. Iyengar, Chandrashekhar B. Khare
Inspired by the patching method of Calegari and Geraghty, and a conjecture of de Smit that has been proved by the first author, we present a conjectural freeness criterion without…
Lim Ulrich sequences and Boij-Söderberg cones
Srikanth B. Iyengar, Linquan Ma, Mark E. Walker
This paper extends the results of Boij, Eisenbud, Erman, Schreyer, and Söderberg on the structure of Betti cones of finitely generated graded modules and finite free complexes ove…