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arXiv · 2512.18875

Genus~0 Gromov-Witten theory of even dimensional complete intersections of two quadrics: the final step

Danil Gubarevich
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Abstract

Even dimensional complete intersections $X$ of two quadrics in projective space are exceptional from the point of view of the Gromov-Witten theory: they are (together with qubic surfaces) the only complete intersections whose Gromov-Witten theory is not invariant under the full orthogonal or symplectic group acting on the primitive cohomology. The genus~0 Gromov-Witten theory of $X$ was studied by Xiaowen Hu. He used geometric arguments and the WDVV equation to compute all genus~0 correlators except one, which cannot be determined by his methods. In this paper we compute the remaining Gromov-Witten invariant of $X$ using Jun Li's degeneration formula.

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Danil Gubarevich. 2025-12-21. Genus~0 Gromov-Witten theory of even dimensional complete intersections of two quadrics: the final step. https://arxiv.org/abs/2512.18875

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