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arXiv · 1401.2631

Monomial transformations of the projective space

Olivier Debarre·Bodo Lass
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Abstract

We prove that, over any field, the dimension of the indeterminacy locus of a rational transformation $f$ of $P^n$ which is defined by monomials of the same degree $d$ with no common factors is at least $(n-2)/2$, provided that the degree of $f$ as a map is not divisible by $d$. This implies upper bounds on the multidegree of $f$.

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Olivier Debarre, Bodo Lass. 2014-01-12. Monomial transformations of the projective space. https://arxiv.org/abs/1401.2631

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