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arXiv · 2403.17681

A Wall Crossing Formula for Motivic Enumerative Invariants

Andrés Jaramillo Puentes
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Abstract

We prove an analog of the wall crossing formula for Welschinger invariants relating the difference of signed curve counting of real curves passing through configurations that differ by a pair of complex conjugated points, and a correspondence Welschinger invariant of the blow up. We prove this analogue for the motivic count of rational curves of fixed degree passing through a generic configuration of points, counted with a motivic multiplicity in the Grothendieck-Witt ring of a base field, extending the notions in the correspondence theorem between motivic invariants for $k$-rational point conditions and tropical curves. We use this formula to compute the degree 4 motivic enumerative invariants of the projective plane counting curves passing through configurations of points defined over quadratic extensions of a base field.

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Andrés Jaramillo Puentes. 2024-03-26. A Wall Crossing Formula for Motivic Enumerative Invariants. https://arxiv.org/abs/2403.17681

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