The real Mordell-Weil group of rational elliptic surfaces and real lines on del Pezzo surfaces of degree $K^2=1$

2024-09-01
Finashin, Sergey
Kharlamov, Viatcheslav
We undertake a study of topological properties of the real Mordell-Weil group $\operatorname{MW}_{\mathbb R}$ of real rational elliptic surfaces $X$ which we accompany by a related study of real lines on $X$ and on the "subordinate" del Pezzo surfaces $Y$ of degree 1. We give an explicit description of isotopy types of real lines on $Y_{\mathbb R}$ and an explicit presentation of $\operatorname{MW}_{\mathbb R}$ in the mapping class group $\operatorname{Mod}(X_{\mathbb R})$. Combining these results we establish an explicit formula for the action of $\operatorname{MW}_{\mathbb R}$ in $H_1(X_{\mathbb R})$.
arXiv
Citation Formats
S. Finashin and V. Kharlamov, “The real Mordell-Weil group of rational elliptic surfaces and real lines on del Pezzo surfaces of degree $K^2=1$,” arXiv, no. 2409.01202, pp. 1–50, 2024, Accessed: 00, 2025. [Online]. Available: http://arxiv.org/pdf/2409.01202v1.