English

The Upsilon function of L-space knots is a Legendre transform

Geometric Topology 2015-06-25 v2

Abstract

Given an L-space knot we show that its Upsilon function is the Legendre transform of a counting function equivalent to the d-invariants of its large surgeries. The unknotting obstruction obtained for the Upsilon function is, in the case of L-space knots, contained in the d-invariants of large surgeries. Generalizations apply for connected sums of L-space knots, which imply that the slice obstruction provided by Upsilon on the subgroup of concordance generated by L-space knots is no finer than that provided by the d-invariants.

Keywords

Cite

@article{arxiv.1505.06672,
  title  = {The Upsilon function of L-space knots is a Legendre transform},
  author = {Maciej Borodzik and Matthew Hedden},
  journal= {arXiv preprint arXiv:1505.06672},
  year   = {2015}
}

Comments

version 2: 13 pages. Question 1.5 asked in the first version is answered negatively

R2 v1 2026-06-22T09:40:55.237Z