Holomorphic Triangles in the Heegaard Floer Pillowcase
Abstract
The Heegaard Floer pillowcase is a recurring local model for rational tangle replacement and exact-triangle constructions. We compute the triangle product for its standard rational-slope triples of curves and encode all contributing classes in a finite generating polynomial. One slope ordering gives a vanishing map. For the other, a closed form for the generating function is computed. One may assume that the slopes are 1/0,p/q and p'/q'. When an integer lies between the two finite slopes, the closed form has a particularly simple description and there are exactly 2(pq'−p'q)+2qq' contributing classes. We also compute the absolute Maslov bi-gradings of the intersection generators in the employed model, relating the planar labels to the graded Floer groups of two-bridge knots and links.
Related
- Surgery Exact Triangles in Involutive Heegaard Floer Homology
- New Heegaard Floer slice genus and clasp number bounds
- U torsion structure in Heegaard Floer homology
- Grid triples, link cobordisms in CPbar and the computation of Heegaard-Floer TQFT
- Instanton and pillowcase homology of the (−2,3,q) pretzel knots
BibTeX
@misc{eftekhary2026holomorphic,
title = {{Holomorphic Triangles in the Heegaard Floer Pillowcase}},
author = {Eaman Eftekhary and Marzieh Souri},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.21153},
eprint = {2610.21153},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.21153},
}
RIS
TY - UNPB
TI - Holomorphic Triangles in the Heegaard Floer Pillowcase
AU - Eaman Eftekhary
AU - Marzieh Souri
PY - 2026
DA - 2026/10/15
PB - arXiv
DO - 10.48550/arxiv.2610.21153
UR - https://arxiv.org/abs/2610.21153
AB - The Heegaard Floer pillowcase is a recurring local model for rational tangle replacement and exact-triangle constructions. We compute the triangle product for its standard rational-slope triples of curves and encode all contributing classes in a finite generating polynomial. One slope ordering gives a vanishing map. For the other, a closed form for the generating function is computed. One may assume that the slopes are 1/0,p/q and p'/q'. When an integer lies between the two finite slopes, the closed form has a particularly simple description and there are exactly 2(pq'−p'q)+2qq' contributing classes. We also compute the absolute Maslov bi-gradings of the intersection generators in the employed model, relating the planar labels to the graded Floer groups of two-bridge knots and links.
ER -