Monday, October 19th, 2026
Math Event: Symplectic Geometry, Gauge Theory, and Low-Dimensional Topology Seminar: Adi Dickstein - Symplectophagy
Time: 12:30 PM - 1:55 PM
Location: Math P-131
Speaker: Adi Dickstein
Abstract: A symplectophagy is a symplectic isotopy satisfying certain constraints reminiscent of the symplectic camel problem. In this talk, I will introduce this notion and basic examples, and present a new phenomenon of symplectic rigidity in the form of obstructions to the existence of symplectophagies in certain situations. To establish these obstructions, we adapt structural arguments from algebraic topology using relative symplectic cohomology, introduced by Varolgunes, and its extension to pairs (joint with Ganor, Polterovich, and Zapolsky), leveraging recent computations of this cohomology with Ganor. By extracting capacity-like information from the torsion, we utilize this algebraic framework to derive the obstructions. This talk is based on work in progress with Ganor and Zapolsky.
Speaker: Adi Dickstein
Abstract: A symplectophagy is a symplectic isotopy satisfying certain constraints reminiscent of the symplectic camel problem. In this talk, I will introduce this notion and basic examples, and present a new phenomenon of symplectic rigidity in the form of obstructions to the existence of symplectophagies in certain situations. To establish these obstructions, we adapt structural arguments from algebraic topology using relative symplectic cohomology, introduced by Varolgunes, and its extension to pairs (joint with Ganor, Polterovich, and Zapolsky), leveraging recent computations of this cohomology with Ganor. By extracting capacity-like information from the torsion, we utilize this algebraic framework to derive the obstructions. This talk is based on work in progress with Ganor and Zapolsky.
Wednesday, October 21st, 2026
Math Event: Algebraic Geometry Seminar: Shengjing Xu - Moduli Space of Residue Parameters and Lagrangian Correspondence for \(\lambda\)-Connections
Time: 4:00 PM - 5:00 PM
Location:
Speaker: Shengjing Xu
Abstract: \(\lambda\)-connections interpolate between Higgs bundles and holomorphic connections on a smooth projective curve. In this talk, I will introduce residue parameters associated with a \(\lambda\)-connection together with a suitable choice of a line subbundle. These residue parameters measure the difference between the \(\lambda\)-connection triple and the oper triple. I will describe their moduli space and explain its relationship with Calogero–Moser spaces. In the end, I will discuss the construction of families of holomorphic Lagrangians in moduli spaces of \(\lambda\)-connections, as well as Lagrangian correspondences between moduli of \(\lambda\)-connections and the moduli of residue parameters. This is joint work with Daebeom Choi.
Speaker: Shengjing Xu
Abstract: \(\lambda\)-connections interpolate between Higgs bundles and holomorphic connections on a smooth projective curve. In this talk, I will introduce residue parameters associated with a \(\lambda\)-connection together with a suitable choice of a line subbundle. These residue parameters measure the difference between the \(\lambda\)-connection triple and the oper triple. I will describe their moduli space and explain its relationship with Calogero–Moser spaces. In the end, I will discuss the construction of families of holomorphic Lagrangians in moduli spaces of \(\lambda\)-connections, as well as Lagrangian correspondences between moduli of \(\lambda\)-connections and the moduli of residue parameters. This is joint work with Daebeom Choi.