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arXiv · 2610.02445

On wall-crossing invariant combinations of Welschinger numbers for rational surfaces with a conic bundle

Sergey Finashin·Viatcheslav Kharlamov
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Abstract

We refine the real enumerative invariants insensitive to changes in the real structure introduced in our previous paper on del Pezzo surfaces, and extend these refined invariants to arbitrary rational surfaces. The construction involves a choice of an auxiliary conic bundle together with a Pin-structure. We prove that the resulting invariants are independent of these auxiliary choices and establish recursive relations for their computation.

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Sergey Finashin, Viatcheslav Kharlamov. 2026-10-01. On wall-crossing invariant combinations of Welschinger numbers for rational surfaces with a conic bundle. https://arxiv.org/abs/2610.02445

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