Abstract
A complex algebraic variety X defined over the real numbers is called an M-variety if the sum of its Betti numbers (for homology with closed supports and coefficients in \(\mathbb{Z} /2\)) coincides with the corresponding sum for the real part of X. It has been known for a long time that any nonsingular complete toric variety is an M-variety. In this paper we consider whether this remains true for toric varieties that are singular or not complete, and we give a positive answer when the dimension of X is less than or equal to 3 or when X is complete with isolated singularities.
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An erratum to this article can be found at http://dx.doi.org/10.1007/s00229-006-0019-5
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Bihan, F., Franz, M., McCrory, C. et al. Is Every Toric Variety an M-Variety?. manuscripta math. 120, 217–232 (2006). https://doi.org/10.1007/s00229-006-0004-z
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DOI: https://doi.org/10.1007/s00229-006-0004-z