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arXiv · 2207.11150

Movable cones of complete intersections of multidegree one on products of projective spaces

Michael Hoff·Isabel Stenger·José Ignacio Yáñez
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Abstract

We study Calabi-Yau manifolds which are complete intersections of hypersurfaces of multidegree $1$ in an $m$-fold product of $n$-dimensional projective spaces. Using the theory of Coxeter groups, we show that the birational automorphism group of such a Calabi-Yau manifold $X$ is infinite and a free product of copies of $\mathbb{Z}$ . Moreover, we give an explicit description of the boundary of the movable cone $\overline{\operatorname{Mov}}(X)$. In the end, we consider examples for the general and non-general case and picture the movable cone and the fundamental domain for the action of $\operatorname{Bir}(X)$.

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Michael Hoff, Isabel Stenger, José Ignacio Yáñez. 2022-07-22. Movable cones of complete intersections of multidegree one on products of projective spaces. https://arxiv.org/abs/2207.11150

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