A characterization of the Zn ⊕Z(δ) lattice and definite nonunimodular intersection forms
Autor: | Saso Strle, Brendan Owens |
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Rok vydání: | 2012 |
Předmět: | |
Zdroj: | American Journal of Mathematics. 134:891-913 |
ISSN: | 1080-6377 |
Popis: | We prove a generalization of Elkies' characterization of the ${\Bbb{Z}}^n$ lattice to nonunimodular definite forms (and lattices). Combined with inequalities of Fr{\o}yshov and of Ozsv\'{a}th and Szab\'{o}, this gives a simple test of whether a rational homology three-sphere may bound a definite four-manifold. As an example we show that small positive surgeries on torus knots do not bound negative-definite four-manifolds. |
Databáze: | OpenAIRE |
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