Seidel's long exact sequence conjecture for composed Dehn twists

Let (M,ω)(M,\omega) be a symplectic manifold of dimension 2d2d with 2c1(M,ω)=02c_1(M,\omega)=0, and let L1,,LnL_1,\dots,L_n be graded Lagrangian spheres. Let A\mathcal{A} be the directed Fukaya category with morphism complexes

homA(Lj,Lk)={CF(Lj,Lk)j<k,Kejj=k,0j>k.\operatorname{hom}_{\mathcal{A}}(L_j,L_k)=\begin{cases}CF(L_j,L_k)&j<k,\\ \mathbb{K}e_j&j=k,\\ 0&j>k.\end{cases}

Set τ=τ1τn\tau=\tau_1\circ\cdots\circ\tau_n. Seidel's conjecture. There is a long exact sequence

H(D)HF(id)HF(τ),\cdots\rightarrow H^*(D)\rightarrow HF^*(\operatorname{id})\rightarrow HF^*(\tau)\rightarrow\cdots,

where DD is the cochain complex

1kn1i1<<iknCF(Lik,Li1)CF(Lik1,Lik)CF(Li1,Li2)[d+n]\bigoplus_{1\leq k\leq n}\bigoplus_{1\leq i_1<\cdots<i_k\leq n}CF(L_{i_k},L_{i_1})\otimes CF(L_{i_{k-1}},L_{i_k})\cdots\otimes CF(L_{i_1},L_{i_2})[d+n]

with a differential analogous to the Hochschild differential. This conjecture seeks to compute the fixed-point Floer homology of the composed Dehn twists from the topology of MM and the directed Fukaya-category morphism complexes. The paper proves an exact sequence of this form, so the conjecture is resolved.

Sources & referencesView supporting material

Primary source

Shuo Zhang, “A long exact sequence on the composition of Dehn twists”, arXiv:2311.14192 (2023).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.