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Euler characteristic of primitive T-hypersurfaces and maximal surfaces

Published online by Cambridge University Press:  23 July 2009

Benoit Bertrand
Affiliation:
Institut de Mathématiques de Toulouse, IUT de Tarbes, 1 rue Lautréamont, BP 1624, 65016 Tarbes cedex, France (benoit.bertrand@iut-tarbes.fr)

Abstract

Viro method plays an important role in the study of topology of real algebraic hypersurfaces. The T-primitive hypersurfaces we study here appear as the result of Viro's combinatorial patchworking when one starts with a primitive triangulation. We show that the Euler characteristic of the real part of such a hypersurface of even dimension is equal to the signature of its complex part. We explain how this can be understood in tropical geometry. We use this result to prove the existence of maximal surfaces in some three-dimensional toric varieties, namely those corresponding to Nakajima polytopes.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2010

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