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arXiv · 2302.04937

Forms of del Pezzo surfaces of degree 5 and 6

Alexandr Zaitsev
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Abstract

In this paper we obtain necessary and sufficient condition for existence of del Pezzo surfaces of degree $5$ and $6$ over a field $K$ with a prescribed action of absolute Galois group $\text{Gal} ( K^{\text{sep}}/K)$ on the graph of $(-1)$-curves. Also we compute automorphism groups of del Pezzo surfaces of degree $5$ over arbitrary fields.

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Alexandr Zaitsev. 2023-02-09. Forms of del Pezzo surfaces of degree 5 and 6. https://arxiv.org/abs/2302.04937

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