Lagrangian Surplusection Phenomena

Suppose you have a family of Lagrangian submanifolds ₜ and an auxiliary Lagrangian . Suppose that intersects some of the ₜ more than the minimal number of times. Can you eliminate surplus intersection (surplusection) with all fibres by performing a Hamiltonian isotopy of ? Or will any Lagrangian is...

Full description

Saved in:
Bibliographic Details
Published in:Symmetry, Integrability and Geometry: Methods and Applications
Date:2024
Main Authors: Dimitroglou Rizell, Georgios, Evans, Jonathan David
Format: Article
Language:English
Published: Інститут математики НАН України 2024
Online Access:https://nasplib.isofts.kiev.ua/handle/123456789/212783
Tags: Add Tag
No Tags, Be the first to tag this record!
Journal Title:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Cite this:Lagrangian Surplusection Phenomena. Georgios Dimitroglou Rizell and Jonathan David Evans. SIGMA 20 (2024), 109, 13 pages

Institution

Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1862692699515125760
author Dimitroglou Rizell, Georgios
Evans, Jonathan David
author_facet Dimitroglou Rizell, Georgios
Evans, Jonathan David
citation_txt Lagrangian Surplusection Phenomena. Georgios Dimitroglou Rizell and Jonathan David Evans. SIGMA 20 (2024), 109, 13 pages
collection DSpace DC
container_title Symmetry, Integrability and Geometry: Methods and Applications
description Suppose you have a family of Lagrangian submanifolds ₜ and an auxiliary Lagrangian . Suppose that intersects some of the ₜ more than the minimal number of times. Can you eliminate surplus intersection (surplusection) with all fibres by performing a Hamiltonian isotopy of ? Or will any Lagrangian isotopic to surplusect some of the fibres? We argue that in several important situations, surplusection cannot be eliminated, and that a better understanding of surplusection phenomena (better bounds and a clearer understanding of how the surplusection is distributed in the family) would help to tackle some outstanding problems in different areas, including Oh's conjecture on the volume-minimising property of the Clifford torus and the concurrent normals conjecture in convex geometry. We pose many open questions.
first_indexed 2026-03-17T23:35:33Z
format Article
fulltext
id nasplib_isofts_kiev_ua-123456789-212783
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 1815-0659
language English
last_indexed 2026-03-17T23:35:33Z
publishDate 2024
publisher Інститут математики НАН України
record_format dspace
spelling Dimitroglou Rizell, Georgios
Evans, Jonathan David
2026-02-11T10:37:52Z
2024
Lagrangian Surplusection Phenomena. Georgios Dimitroglou Rizell and Jonathan David Evans. SIGMA 20 (2024), 109, 13 pages
1815-0659
2020 Mathematics Subject Classification: 53D12; 53D40
arXiv:2408.14883
https://nasplib.isofts.kiev.ua/handle/123456789/212783
https://doi.org/10.3842/SIGMA.2024.109
Suppose you have a family of Lagrangian submanifolds ₜ and an auxiliary Lagrangian . Suppose that intersects some of the ₜ more than the minimal number of times. Can you eliminate surplus intersection (surplusection) with all fibres by performing a Hamiltonian isotopy of ? Or will any Lagrangian isotopic to surplusect some of the fibres? We argue that in several important situations, surplusection cannot be eliminated, and that a better understanding of surplusection phenomena (better bounds and a clearer understanding of how the surplusection is distributed in the family) would help to tackle some outstanding problems in different areas, including Oh's conjecture on the volume-minimising property of the Clifford torus and the concurrent normals conjecture in convex geometry. We pose many open questions.
This note grew out of many conversations with many people, including Chris Evans, Ivan Smith, John Pardon, Umut Varolgunes, Leonid Polterovich, Kai Hugtenburg, Joé Brendel, Felix Schlenk, Elliot Gathercole, Nikolas Adaloglou, and Matt Buck. We are particularly grateful to Egor Shelukhin for pointing out the work of Viterbo [28], which led us to the short paper [12] of Goldstein, both of which give even more evidence for the ubiquity of surplusection (whilst also rendering our original volume bound obsolete). We also thank the referees for their prompt and insightful comments. The EPSRC Grant EP/W015749/1 supports J.E. G.D.R., which is supported by the Knut and Alice Wallenberg Foundation under grants KAW 2021.0191 and KAW 2021.0300, and by the Swedish Research Council under grant 2020-04426.
en
Інститут математики НАН України
Symmetry, Integrability and Geometry: Methods and Applications
Lagrangian Surplusection Phenomena
Article
published earlier
spellingShingle Lagrangian Surplusection Phenomena
Dimitroglou Rizell, Georgios
Evans, Jonathan David
title Lagrangian Surplusection Phenomena
title_full Lagrangian Surplusection Phenomena
title_fullStr Lagrangian Surplusection Phenomena
title_full_unstemmed Lagrangian Surplusection Phenomena
title_short Lagrangian Surplusection Phenomena
title_sort lagrangian surplusection phenomena
url https://nasplib.isofts.kiev.ua/handle/123456789/212783
work_keys_str_mv AT dimitroglourizellgeorgios lagrangiansurplusectionphenomena
AT evansjonathandavid lagrangiansurplusectionphenomena