Abstract
The dual F-signature is a numerical invariant defined via the Frobenius morphism in positive characteristic. It is known that the dual F-signature characterizes some singularities. However, the value of the dual F-signature is not known except in only a few cases. In this paper, we determine the dual F-signature of Cohen-Macaulay modules over two-dimensional rational double points. The method for determining the dual F-signature is also valid for determining the Hilbert-Kunz multiplicity. We discuss it in Appendix.
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Presented by Claus Michael Ringel.
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Nakajima, Y. Dual F-Signature of Cohen-Macaulay Modules Over Rational Double Points. Algebr Represent Theor 18, 1211–1245 (2015). https://doi.org/10.1007/s10468-015-9538-7
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DOI: https://doi.org/10.1007/s10468-015-9538-7
Keywords
- F-signature
- Dual F-signature
- Generalized F-signature
- Hilbert-Kunz multiplicity
- Quotient surface singularities
- Auslander-Reiten quiver