An arithmetic Abramovich--Bertram formula
        
    
    演讲者
            
                                Kirsten Wickelgren
                            
        时间
            
            2024年05月30日 22:00 至 23:00
            
        地点
            
                Online
            
        线上
            
                Zoom 638 227 8222
                (BIMSA)
            
        摘要
            
                Gromov--Witten invariants and Welschinger invariants count curves over the complex and real numbers. In joint work with J. Kass, M. Levine, and J. Solomon, we gave arithmetically meaningful counts of rational curves on smooth del Pezzo surfaces over general fields. This talk concerns how these invariants change under an algebraic analogue of surgery along a Lagrangian sphere. We allow certain del Pezzo surfaces to acquire a -2 curve and study deformations of curves to give an arithmetic enrichment of a formula due to D. Abramovich and A. Bertram over C and due to E. Brugallé and N. Puignau over R. This is joint work with Erwan Brugallé.
            
         
                 
                                         
                                         
                                        