---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '20456'
abstract:
- lang: eng
  text: Given a locally finite set A⊆Rd and a coloring χ:A→{0,1,…,s}, we introduce
    the chromatic Delaunay mosaic of χ, which is a Delaunay mosaic in Rs+d that represents
    how points of different colors mingle. Our main results are bounds on the size
    of the chromatic Delaunay mosaic, in which we assume that d and s are constants.
    For example, if A is finite with n=#A, and the coloring is random, then the chromatic
    Delaunay mosaic has O(n⌈d/2⌉) cells in expectation. In contrast, for Delone sets
    and Poisson point processes in Rd, the expected number of cells within a closed
    ball is only a constant times the number of points in this ball. Furthermore,
    in R2 all colorings of a dense set of n points have chromatic Delaunay mosaics
    of size O(n). This encourages the use of chromatic Delaunay mosaics in applications.
acknowledgement: The fourth author thanks Boris Aronov for insightful discussions
  on the size of the overlay of Voronoi tessellations. Open access funding provided
  by Institute of Science and Technology (IST Austria). This project has received
  funding from the European Research Council (ERC) under the European Union’s Horizon
  2020 research and innovation programme, grant no. 788183, from the Wittgenstein
  Prize, Austrian Science Fund (FWF), grant no. Z 342-N31, and from the DFG Collaborative
  Research Center TRR 109, ‘Discretization in Geometry and Dynamics’, Austrian Science
  Fund (FWF), grant no. I 02979-N35.
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Ranita
  full_name: Biswas, Ranita
  id: 3C2B033E-F248-11E8-B48F-1D18A9856A87
  last_name: Biswas
  orcid: 0000-0002-5372-7890
- first_name: Sebastiano
  full_name: Cultrera di Montesano, Sebastiano
  id: 34D2A09C-F248-11E8-B48F-1D18A9856A87
  last_name: Cultrera di Montesano
  orcid: 0000-0001-6249-0832
- first_name: Ondrej
  full_name: Draganov, Ondrej
  id: 2B23F01E-F248-11E8-B48F-1D18A9856A87
  last_name: Draganov
  orcid: 0000-0003-0464-3823
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: Biswas R, Cultrera di Montesano S, Draganov O, Edelsbrunner H, Saghafian M.
    On the size of chromatic Delaunay mosaics. <i>Discrete and Computational Geometry</i>.
    2026;75:24-47. doi:<a href="https://doi.org/10.1007/s00454-025-00778-7">10.1007/s00454-025-00778-7</a>
  apa: Biswas, R., Cultrera di Montesano, S., Draganov, O., Edelsbrunner, H., &#38;
    Saghafian, M. (2026). On the size of chromatic Delaunay mosaics. <i>Discrete and
    Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-025-00778-7">https://doi.org/10.1007/s00454-025-00778-7</a>
  chicago: Biswas, Ranita, Sebastiano Cultrera di Montesano, Ondrej Draganov, Herbert
    Edelsbrunner, and Morteza Saghafian. “On the Size of Chromatic Delaunay Mosaics.”
    <i>Discrete and Computational Geometry</i>. Springer Nature, 2026. <a href="https://doi.org/10.1007/s00454-025-00778-7">https://doi.org/10.1007/s00454-025-00778-7</a>.
  ieee: R. Biswas, S. Cultrera di Montesano, O. Draganov, H. Edelsbrunner, and M.
    Saghafian, “On the size of chromatic Delaunay mosaics,” <i>Discrete and Computational
    Geometry</i>, vol. 75. Springer Nature, pp. 24–47, 2026.
  ista: Biswas R, Cultrera di Montesano S, Draganov O, Edelsbrunner H, Saghafian M.
    2026. On the size of chromatic Delaunay mosaics. Discrete and Computational Geometry.
    75, 24–47.
  mla: Biswas, Ranita, et al. “On the Size of Chromatic Delaunay Mosaics.” <i>Discrete
    and Computational Geometry</i>, vol. 75, Springer Nature, 2026, pp. 24–47, doi:<a
    href="https://doi.org/10.1007/s00454-025-00778-7">10.1007/s00454-025-00778-7</a>.
  short: R. Biswas, S. Cultrera di Montesano, O. Draganov, H. Edelsbrunner, M. Saghafian,
    Discrete and Computational Geometry 75 (2026) 24–47.
corr_author: '1'
date_created: 2025-10-12T22:01:26Z
date_published: 2026-01-01T00:00:00Z
date_updated: 2026-01-05T13:21:56Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-025-00778-7
ec_funded: 1
external_id:
  arxiv:
  - '2212.03121'
  isi:
  - '001584166900001'
file:
- access_level: open_access
  checksum: 0addb5c1b78142f9fb453bfa04695400
  content_type: application/pdf
  creator: dernst
  date_created: 2026-01-05T13:21:20Z
  date_updated: 2026-01-05T13:21:20Z
  file_id: '20952'
  file_name: 2026_DiscreteCompGeom_Biswas.pdf
  file_size: 570922
  relation: main_file
  success: 1
file_date_updated: 2026-01-05T13:21:20Z
has_accepted_license: '1'
intvolume: '        75'
isi: 1
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: 24-47
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  record:
  - id: '15090'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: On the size of chromatic Delaunay mosaics
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 75
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '20980'
abstract:
- lang: eng
  text: 'Morse decompositions partition the flows in a vector field into equivalent
    structures. Given such a decomposition, one can define a further summary of its
    flow structure by what is called a connection matrix. These matrices, a generalization
    of Morse boundary operators from classical Morse theory, capture the connections
    made by the flows among the critical structures—such as attractors, repellers,
    and orbits—in a vector field. Recently, in the context of combinatorial dynamics,
    an efficient persistence-like algorithm to compute connection matrices has been
    proposed in Dey, Lipiński, Mrozek, and Slechta [SIAM J. Appl. Dyn. Syst., 23 (2024),
    pp. 81–97]. We show that, actually, the classical persistence algorithm with exhaustive
    reduction retrieves connection matrices, both simplifying the algorithm of Dey
    et al. and bringing the theory of persistence closer to combinatorial dynamical
    systems. We supplement this main result with an observation: the concept of persistence
    as defined for scalar fields naturally adapts to Morse decompositions whose Morse
    sets are filtered with a Lyapunov function. We conclude by presenting preliminary
    experimental results.'
acknowledgement: "This research was supported by NSF grants DMS-2301360 and CCF-2437030
  as well as from the European Union's Horizon 2020 research and innovation programme
  under Marie Sk\\lodowska-Curie grant 101034413.\r\n"
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Tamal K.
  full_name: Dey, Tamal K.
  last_name: Dey
- first_name: Andrew
  full_name: Haas, Andrew
  last_name: Haas
- first_name: Michał
  full_name: Lipiński, Michał
  id: dfffb474-4317-11ee-8f5c-fe3fc95a425e
  last_name: Lipiński
  orcid: 0000-0001-9789-9750
citation:
  ama: Dey TK, Haas A, Lipiński M. Computing a connection matrix and persistence efficiently
    from a morse decomposition. <i>SIAM Journal on Applied Dynamical Systems</i>.
    2026;25(1):108-130. doi:<a href="https://doi.org/10.1137/25m1739406">10.1137/25m1739406</a>
  apa: Dey, T. K., Haas, A., &#38; Lipiński, M. (2026). Computing a connection matrix
    and persistence efficiently from a morse decomposition. <i>SIAM Journal on Applied
    Dynamical Systems</i>. Society for Industrial &#38; Applied Mathematics. <a href="https://doi.org/10.1137/25m1739406">https://doi.org/10.1137/25m1739406</a>
  chicago: Dey, Tamal K., Andrew Haas, and Michał Lipiński. “Computing a Connection
    Matrix and Persistence Efficiently from a Morse Decomposition.” <i>SIAM Journal
    on Applied Dynamical Systems</i>. Society for Industrial &#38; Applied Mathematics,
    2026. <a href="https://doi.org/10.1137/25m1739406">https://doi.org/10.1137/25m1739406</a>.
  ieee: T. K. Dey, A. Haas, and M. Lipiński, “Computing a connection matrix and persistence
    efficiently from a morse decomposition,” <i>SIAM Journal on Applied Dynamical
    Systems</i>, vol. 25, no. 1. Society for Industrial &#38; Applied Mathematics,
    pp. 108–130, 2026.
  ista: Dey TK, Haas A, Lipiński M. 2026. Computing a connection matrix and persistence
    efficiently from a morse decomposition. SIAM Journal on Applied Dynamical Systems.
    25(1), 108–130.
  mla: Dey, Tamal K., et al. “Computing a Connection Matrix and Persistence Efficiently
    from a Morse Decomposition.” <i>SIAM Journal on Applied Dynamical Systems</i>,
    vol. 25, no. 1, Society for Industrial &#38; Applied Mathematics, 2026, pp. 108–30,
    doi:<a href="https://doi.org/10.1137/25m1739406">10.1137/25m1739406</a>.
  short: T.K. Dey, A. Haas, M. Lipiński, SIAM Journal on Applied Dynamical Systems
    25 (2026) 108–130.
date_created: 2026-01-12T11:17:06Z
date_published: 2026-01-01T00:00:00Z
date_updated: 2026-01-20T07:40:39Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1137/25m1739406
ec_funded: 1
external_id:
  arxiv:
  - '2502.19369'
intvolume: '        25'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2502.19369
month: '01'
oa: 1
oa_version: Preprint
page: 108-130
project:
- _id: fc2ed2f7-9c52-11eb-aca3-c01059dda49c
  call_identifier: H2020
  grant_number: '101034413'
  name: 'IST-BRIDGE: International postdoctoral program'
publication: SIAM Journal on Applied Dynamical Systems
publication_identifier:
  issn:
  - 1536-0040
publication_status: published
publisher: Society for Industrial & Applied Mathematics
quality_controlled: '1'
scopus_import: '1'
status: public
title: Computing a connection matrix and persistence efficiently from a morse decomposition
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 25
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '21056'
abstract:
- lang: eng
  text: "In this work, we introduce and study what we believe is an intriguing, and,
    to the best of our knowledge, previously unknown connection between two fundamental
    areas in computational topology, namely topological data analysis (TDA) and knot
    theory. Given a function from a topological space to ℝ, TDA provides tools to
    simplify and study the importance of topological features: in particular, the
    \U0001D459^\U0001D461⁢ℎ-dimensional persistence diagram encodes the topological
    changes (or \U0001D459-homology) in the sublevel set as the function value increases
    into a set of points in the plane. Given a continuous one parameter family of
    such functions, we can combine the persistence diagrams into an object known as
    a vineyard, which tracks the evolution of points in the persistence diagram as
    the function changes. If we further restrict that family of functions to be periodic,
    we identify the two ends of the vineyard, yielding a closed vineyard. This allows
    the study of monodromy, which in this context means that following the family
    of functions for a period permutes the set of points in a non-trivial way. Recent
    work has studied monodromy in the directional persistent homology transform, demonstrating
    some interesting connections between an input shape and monodromy in the persistent
    homology transform for 0-dimensional homology embedded in ℝ^2.\r\nIn this work,
    given a link and a value \U0001D459, we construct a topological space (based on
    the given link) and periodic family of functions on this space (based on the Euclidean
    distance function), such that the closed \U0001D459-vineyard contains this link.
    This shows that vineyards are topologically as rich as one could possibly hope,
    suggesting many future directions of work. Importantly, it has at least two immediate
    consequences we explicitly point out:\r\n1.\tMonodromy of any periodicity can
    occur in a \U0001D459-vineyard for any \U0001D459. This answers a variant of a
    question by Arya and collaborators. To exhibit this as a consequence of our first
    main result we also reformulate monodromy in a more geometric way, which may be
    of interest in itself.\r\n2.\tTopologically distinguishing closed vineyards is
    likely to be difficult (from a complexity theory as well as from a practical perspective)
    because of the difficulty of knot and link recognition, which have strong connections
    to many NP-hard problems."
acknowledgement: We thank the reviewers for both SODA and ATMCS for their comments,
  whichimproved the exposition. We thank Kate Turner for discussion and Clément Maria
  for pointing out thatAlexander’s theorem was already (well) known. Mathijs Wintraecken
  would like to express his gratitude tothe administrative support he received from
  University of Notre Dame during his visit and from Sophie Honnoratand Stephanie
  Verdonck at Inria in general.This work has been supported by the ANR grant StratMesh,
  ANR-24-CE48-1899, by NSF award 2444309, andthe welcome package from IDEX of the
  Université Côte d’Azur, ANR-15-IDEX-01.
article_processing_charge: No
arxiv: 1
author:
- first_name: Erin W.
  full_name: Chambers, Erin W.
  last_name: Chambers
- first_name: Christopher D
  full_name: Fillmore, Christopher D
  id: 35638A5C-AAC7-11E9-B0BF-5503E6697425
  last_name: Fillmore
- first_name: Elizabeth R
  full_name: Stephenson, Elizabeth R
  id: 2D04F932-F248-11E8-B48F-1D18A9856A87
  last_name: Stephenson
  orcid: 0000-0002-6862-208X
- first_name: Mathijs
  full_name: Wintraecken, Mathijs
  id: 307CFBC8-F248-11E8-B48F-1D18A9856A87
  last_name: Wintraecken
  orcid: 0000-0002-7472-2220
citation:
  ama: 'Chambers EW, Fillmore CD, Stephenson ER, Wintraecken M. Braiding Vineyards.
    In: Green Larsen K, Saha B, eds. <i>Proceedings of the 2026 Annual ACM-SIAM Symposium
    on Discrete Algorithms</i>. Philadelphia, PA, United States: Society for Industrial
    and Applied Mathematics; 2026:6240-6263. doi:<a href="https://doi.org/10.1137/1.9781611978971.225">10.1137/1.9781611978971.225</a>'
  apa: 'Chambers, E. W., Fillmore, C. D., Stephenson, E. R., &#38; Wintraecken, M.
    (2026). Braiding Vineyards. In K. Green Larsen &#38; B. Saha (Eds.), <i>Proceedings
    of the 2026 Annual ACM-SIAM Symposium on Discrete Algorithms</i> (pp. 6240–6263).
    Philadelphia, PA, United States: Society for Industrial and Applied Mathematics.
    <a href="https://doi.org/10.1137/1.9781611978971.225">https://doi.org/10.1137/1.9781611978971.225</a>'
  chicago: 'Chambers, Erin W., Christopher D Fillmore, Elizabeth R Stephenson, and
    Mathijs Wintraecken. “Braiding Vineyards.” In <i>Proceedings of the 2026 Annual
    ACM-SIAM Symposium on Discrete Algorithms</i>, edited by Kasper Green Larsen and
    Barna Saha, 6240–63. Philadelphia, PA, United States: Society for Industrial and
    Applied Mathematics, 2026. <a href="https://doi.org/10.1137/1.9781611978971.225">https://doi.org/10.1137/1.9781611978971.225</a>.'
  ieee: 'E. W. Chambers, C. D. Fillmore, E. R. Stephenson, and M. Wintraecken, “Braiding
    Vineyards,” in <i>Proceedings of the 2026 Annual ACM-SIAM Symposium on Discrete
    Algorithms</i>, K. Green Larsen and B. Saha, Eds. Philadelphia, PA, United States:
    Society for Industrial and Applied Mathematics, 2026, pp. 6240–6263.'
  ista: 'Chambers EW, Fillmore CD, Stephenson ER, Wintraecken M. 2026.Braiding Vineyards.
    In: Proceedings of the 2026 Annual ACM-SIAM Symposium on Discrete Algorithms.
    , 6240–6263.'
  mla: Chambers, Erin W., et al. “Braiding Vineyards.” <i>Proceedings of the 2026
    Annual ACM-SIAM Symposium on Discrete Algorithms</i>, edited by Kasper Green Larsen
    and Barna Saha, Society for Industrial and Applied Mathematics, 2026, pp. 6240–63,
    doi:<a href="https://doi.org/10.1137/1.9781611978971.225">10.1137/1.9781611978971.225</a>.
  short: E.W. Chambers, C.D. Fillmore, E.R. Stephenson, M. Wintraecken, in:, K. Green
    Larsen, B. Saha (Eds.), Proceedings of the 2026 Annual ACM-SIAM Symposium on Discrete
    Algorithms, Society for Industrial and Applied Mathematics, Philadelphia, PA,
    United States, 2026, pp. 6240–6263.
date_created: 2026-01-28T12:58:16Z
date_published: 2026-01-07T00:00:00Z
date_updated: 2026-02-16T08:06:23Z
day: '07'
department:
- _id: HeEd
doi: 10.1137/1.9781611978971.225
editor:
- first_name: Kasper
  full_name: Green Larsen, Kasper
  last_name: Green Larsen
- first_name: Barna
  full_name: Saha, Barna
  last_name: Saha
external_id:
  arxiv:
  - '2504.11203'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2504.11203
month: '01'
oa: 1
oa_version: Preprint
page: 6240-6263
place: Philadelphia, PA, United States
publication: Proceedings of the 2026 Annual ACM-SIAM Symposium on Discrete Algorithms
publication_identifier:
  eisbn:
  - '9781611978971'
publication_status: published
publisher: Society for Industrial and Applied Mathematics
quality_controlled: '1'
related_material:
  record:
  - id: '21051'
    relation: earlier_version
    status: public
status: public
title: Braiding Vineyards
type: book_chapter
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2026'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
PlanS_conform: '1'
_id: '21115'
abstract:
- lang: eng
  text: Quantifying cell morphology is central to understanding cellular regulation,
    fate, and heterogeneity, yet conventional image-based analyses often struggle
    with diverse or irregular shapes. We present a computational framework that uses
    topological data analysis to characterise and compare single-cell morphologies
    from fluorescence microscopy. Each cell is represented by its contour together
    with the position of its nucleus, from which we construct a filtration based on
    a radial distance function and derive a persistence diagram encoding the shape’s
    topological evolution. The similarity between two cells is quantified using the
    2-Wasserstein distance between their diagrams, yielding a shape distance we call
    the PH distance. We apply this method to two representative experimental systems—primary
    human mesenchymal stem cells (hMSCs) and HeLa cells—and show that PH distances
    enable the detection of outliers in those systems, the identification of sub-populations,
    and the quantification of shape heterogeneity. We benchmark PH against three established
    contour-based distances (aspect ratio, Fourier descriptors, and elastic shape
    analysis) and show that PH offers better separation between cell types and greater
    robustness when clustering heterogeneous populations. Together, these results
    demonstrate that persistent-homology-based signatures provide a principled and
    sensitive approach for analysing cell morphology in settings where traditional
    geometric or image-based descriptors are insufficient.
acknowledgement: We thank Stephan Huckemann, Katharine Turner, Benjamin Eltzner, Stephan
  Tillmann, Fariza Rashid, Vanessa Robins, and Lamiae Azizi for many useful discussions
  at various stages of this project. FR and PY gratefully acknowledge Matthias Weiss
  (Experimental Physics I, University of Bayreuth, Germany) for granting access to
  cell culture and laboratories, as well as funding consumables and the fruitful discussion
  that contributed to this work. For open access purposes, the author has applied
  a CC BY public copyright license to any author-accepted manuscript version arising
  from this submission.
article_number: e1013890
article_processing_charge: Yes
article_type: original
author:
- first_name: Yossi
  full_name: Bleile, Yossi
  id: 920a7385-7995-11ef-9bfd-8c434cd8f3c2
  last_name: Bleile
  orcid: 0000-0002-4861-9174
- first_name: Pooja
  full_name: Yadav, Pooja
  last_name: Yadav
- first_name: Patrice
  full_name: Koehl, Patrice
  last_name: Koehl
- first_name: Florian
  full_name: Rehfeldt, Florian
  last_name: Rehfeldt
citation:
  ama: 'Bleile Y, Yadav P, Koehl P, Rehfeldt F. Persistence diagrams as morphological
    signatures of cells: A method to measure and compare cells within a population.
    <i>PLoS Computational Biology</i>. 2026;22. doi:<a href="https://doi.org/10.1371/journal.pcbi.1013890">10.1371/journal.pcbi.1013890</a>'
  apa: 'Bleile, Y., Yadav, P., Koehl, P., &#38; Rehfeldt, F. (2026). Persistence diagrams
    as morphological signatures of cells: A method to measure and compare cells within
    a population. <i>PLoS Computational Biology</i>. Public Library of Science. <a
    href="https://doi.org/10.1371/journal.pcbi.1013890">https://doi.org/10.1371/journal.pcbi.1013890</a>'
  chicago: 'Bleile, Yossi, Pooja Yadav, Patrice Koehl, and Florian Rehfeldt. “Persistence
    Diagrams as Morphological Signatures of Cells: A Method to Measure and Compare
    Cells within a Population.” <i>PLoS Computational Biology</i>. Public Library
    of Science, 2026. <a href="https://doi.org/10.1371/journal.pcbi.1013890">https://doi.org/10.1371/journal.pcbi.1013890</a>.'
  ieee: 'Y. Bleile, P. Yadav, P. Koehl, and F. Rehfeldt, “Persistence diagrams as
    morphological signatures of cells: A method to measure and compare cells within
    a population,” <i>PLoS Computational Biology</i>, vol. 22. Public Library of Science,
    2026.'
  ista: 'Bleile Y, Yadav P, Koehl P, Rehfeldt F. 2026. Persistence diagrams as morphological
    signatures of cells: A method to measure and compare cells within a population.
    PLoS Computational Biology. 22, e1013890.'
  mla: 'Bleile, Yossi, et al. “Persistence Diagrams as Morphological Signatures of
    Cells: A Method to Measure and Compare Cells within a Population.” <i>PLoS Computational
    Biology</i>, vol. 22, e1013890, Public Library of Science, 2026, doi:<a href="https://doi.org/10.1371/journal.pcbi.1013890">10.1371/journal.pcbi.1013890</a>.'
  short: Y. Bleile, P. Yadav, P. Koehl, F. Rehfeldt, PLoS Computational Biology 22
    (2026).
corr_author: '1'
date_created: 2026-01-30T10:36:32Z
date_published: 2026-01-28T00:00:00Z
date_updated: 2026-02-12T14:23:54Z
day: '28'
ddc:
- '000'
department:
- _id: HeEd
doi: 10.1371/journal.pcbi.1013890
external_id:
  pmid:
  - '41604421'
file:
- access_level: open_access
  checksum: 3899d929ee9be0453c95524e49992d72
  content_type: application/pdf
  creator: dernst
  date_created: 2026-02-10T07:13:06Z
  date_updated: 2026-02-10T07:13:06Z
  file_id: '21204'
  file_name: 2026_PloSCompBio_Bleile.pdf
  file_size: 8908746
  relation: main_file
  success: 1
file_date_updated: 2026-02-10T07:13:06Z
has_accepted_license: '1'
intvolume: '        22'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
pmid: 1
publication: PLoS Computational Biology
publication_identifier:
  issn:
  - 1553-7358
publication_status: published
publisher: Public Library of Science
quality_controlled: '1'
related_material:
  link:
  - relation: software
    url: https://github.com/yossibokorbleile/correa
scopus_import: '1'
status: public
title: 'Persistence diagrams as morphological signatures of cells: A method to measure
  and compare cells within a population'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 22
year: '2026'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '21232'
abstract:
- lang: eng
  text: "<jats:title>Abstract</jats:title>\r\n                  <jats:p>In this paper,
    we consider a simple class of stratified spaces – 2-complexes. We present an algorithm
    that learns the abstract structure of an embedded 2-complex from a point cloud
    sampled from it. We use tools and inspiration from computational geometry, algebraic
    topology, and topological data analysis and prove the correctness of the identified
    abstract structure under assumptions on the embedding.</jats:p>"
acknowledgement: The author would like to thank Kate Turner, Chris Williams, Jonathan
  Spreer, Stephan Tillmann, Vanessa Robins, Vigleik Angeltveit, Martin Helmer, and
  James Morgan for very helpful discussions; and thanks Sara Kališnik Hintz and Paul
  Bendich for comments on an earlier version. Additonally, the author would like to
  thank both reviewers for their very insightful and helpful comments, without which
  the paper would be infinitely less coherent than it currently is. Open access funding
  provided by Institute of Science and Technology (IST Austria). The work in this
  paper was supported by an Australian Federal Government Grant, 2019-2022, Stratified
  Space Learning.
article_number: '17'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Yossi
  full_name: Bleile, Yossi
  id: 920a7385-7995-11ef-9bfd-8c434cd8f3c2
  last_name: Bleile
  orcid: 0000-0002-4861-9174
citation:
  ama: 'Bleile Y. Towards stratified space learning: 2-complexes. <i>La Matematica</i>.
    2026;5. doi:<a href="https://doi.org/10.1007/s44007-025-00183-9">10.1007/s44007-025-00183-9</a>'
  apa: 'Bleile, Y. (2026). Towards stratified space learning: 2-complexes. <i>La Matematica</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s44007-025-00183-9">https://doi.org/10.1007/s44007-025-00183-9</a>'
  chicago: 'Bleile, Yossi. “Towards Stratified Space Learning: 2-Complexes.” <i>La
    Matematica</i>. Springer Nature, 2026. <a href="https://doi.org/10.1007/s44007-025-00183-9">https://doi.org/10.1007/s44007-025-00183-9</a>.'
  ieee: 'Y. Bleile, “Towards stratified space learning: 2-complexes,” <i>La Matematica</i>,
    vol. 5. Springer Nature, 2026.'
  ista: 'Bleile Y. 2026. Towards stratified space learning: 2-complexes. La Matematica.
    5, 17.'
  mla: 'Bleile, Yossi. “Towards Stratified Space Learning: 2-Complexes.” <i>La Matematica</i>,
    vol. 5, 17, Springer Nature, 2026, doi:<a href="https://doi.org/10.1007/s44007-025-00183-9">10.1007/s44007-025-00183-9</a>.'
  short: Y. Bleile, La Matematica 5 (2026).
corr_author: '1'
date_created: 2026-02-16T10:44:44Z
date_published: 2026-02-08T00:00:00Z
date_updated: 2026-02-23T10:20:10Z
day: '08'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s44007-025-00183-9
external_id:
  arxiv:
  - '2305.02724'
file:
- access_level: open_access
  checksum: 6cae2efb47b025af22a8539c606a4e09
  content_type: application/pdf
  creator: dernst
  date_created: 2026-02-23T10:18:52Z
  date_updated: 2026-02-23T10:18:52Z
  file_id: '21347'
  file_name: 2026_LaMatematica_Bleile.pdf
  file_size: 15051582
  relation: main_file
  success: 1
file_date_updated: 2026-02-23T10:18:52Z
has_accepted_license: '1'
intvolume: '         5'
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
publication: La Matematica
publication_identifier:
  issn:
  - 2730-9657
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Towards stratified space learning: 2-complexes'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 5
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '21374'
abstract:
- lang: eng
  text: "Let . S be a set of distinct points in general position in the\r\nEuclidean
    plane. A plane Hamiltonian path on . S is a crossing-free geometric path such
    that every point of .S is a vertex of the path. It is\r\nknown that, if. S is
    sufficiently large, there exist three edge-disjoint plane\r\nHamiltonian paths
    on . S. In this paper we study an edge-constrained\r\nversion of the problem of
    finding Hamiltonian paths on a point set. We\r\nfirst consider the problem of
    finding a single plane Hamiltonian path . π\r\nwith endpoints .s, t ∈ S and constraints
    given by a segment . ab, where\r\n.a, b ∈ S. We consider the following scenarios:
    (i) .ab ∈ π; (ii) .ab π. We\r\ncharacterize those quintuples . S, a, b, s, t for
    which . π exists. Secondly,\r\nwe consider the problem of finding two plane Hamiltonian
    paths . π1, π2\r\non a set . S with constraints given by a segment . ab, where
    .a, b ∈ S. We\r\nconsider the following scenarios: (i) .π1 and .π2 share no edges
    and .ab is\r\nan edge of . π1; (ii) .π1 and .π2 share no edges and none of them
    includes\r\n.ab as an edge; (iii) both .π1 and .π2 include .ab as an edge and
    share no\r\nother edges. In all cases, we characterize those triples . S, a, b
    for which\r\n.π1 and .π2 exist."
acknowledgement: "We thank the organizers of the HOMONOLO 2024 workshop in Nová Louka,
  Czech Republic, for the fruitful atmosphere where the research on this project was
  initiated.\r\n\r\nT. Antić, A. Džuklevski, J. Kratochvíl and M. Saumell received
  funding from GAČR grant 23–04949X, T.A and A.Dž were additionally supported by GAUK
  grant SVV–2025–260822. G. Liotta was supported in part by MUR of Italy, PRIN Project
  no. 2022TS4Y3N – EXPAND and PON Project ARS01_00540. J. Fiala was in part supported
  by GAČR grant 25-16847S."
alternative_title:
- LNCS
article_processing_charge: No
arxiv: 1
author:
- first_name: Todor
  full_name: Antić, Todor
  last_name: Antić
- first_name: Aleksa
  full_name: Džuklevski, Aleksa
  last_name: Džuklevski
- first_name: Jiří
  full_name: Fiala, Jiří
  last_name: Fiala
- first_name: Jan
  full_name: Kratochvíl, Jan
  last_name: Kratochvíl
- first_name: Giuseppe
  full_name: Liotta, Giuseppe
  last_name: Liotta
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
- first_name: Maria
  full_name: Saumell, Maria
  last_name: Saumell
- first_name: Johannes
  full_name: Zink, Johannes
  last_name: Zink
citation:
  ama: 'Antić T, Džuklevski A, Fiala J, et al. Edge-constrained Hamiltonian paths
    on a point set. In: <i>51st International Conference on Current Trends in Theory
    and Practice of Computer Science</i>. Vol 16448. Springer Nature; 2026:532-546.
    doi:<a href="https://doi.org/10.1007/978-3-032-17801-5_39">10.1007/978-3-032-17801-5_39</a>'
  apa: 'Antić, T., Džuklevski, A., Fiala, J., Kratochvíl, J., Liotta, G., Saghafian,
    M., … Zink, J. (2026). Edge-constrained Hamiltonian paths on a point set. In <i>51st
    International Conference on Current Trends in Theory and Practice of Computer
    Science</i> (Vol. 16448, pp. 532–546). Krakow, Poland: Springer Nature. <a href="https://doi.org/10.1007/978-3-032-17801-5_39">https://doi.org/10.1007/978-3-032-17801-5_39</a>'
  chicago: Antić, Todor, Aleksa Džuklevski, Jiří Fiala, Jan Kratochvíl, Giuseppe Liotta,
    Morteza Saghafian, Maria Saumell, and Johannes Zink. “Edge-Constrained Hamiltonian
    Paths on a Point Set.” In <i>51st International Conference on Current Trends in
    Theory and Practice of Computer Science</i>, 16448:532–46. Springer Nature, 2026.
    <a href="https://doi.org/10.1007/978-3-032-17801-5_39">https://doi.org/10.1007/978-3-032-17801-5_39</a>.
  ieee: T. Antić <i>et al.</i>, “Edge-constrained Hamiltonian paths on a point set,”
    in <i>51st International Conference on Current Trends in Theory and Practice of
    Computer Science</i>, Krakow, Poland, 2026, vol. 16448, pp. 532–546.
  ista: 'Antić T, Džuklevski A, Fiala J, Kratochvíl J, Liotta G, Saghafian M, Saumell
    M, Zink J. 2026. Edge-constrained Hamiltonian paths on a point set. 51st International
    Conference on Current Trends in Theory and Practice of Computer Science. SOFSEM:
    Conference on Current Trends in Theory and Practice of Computer Science, LNCS,
    vol. 16448, 532–546.'
  mla: Antić, Todor, et al. “Edge-Constrained Hamiltonian Paths on a Point Set.” <i>51st
    International Conference on Current Trends in Theory and Practice of Computer
    Science</i>, vol. 16448, Springer Nature, 2026, pp. 532–46, doi:<a href="https://doi.org/10.1007/978-3-032-17801-5_39">10.1007/978-3-032-17801-5_39</a>.
  short: T. Antić, A. Džuklevski, J. Fiala, J. Kratochvíl, G. Liotta, M. Saghafian,
    M. Saumell, J. Zink, in:, 51st International Conference on Current Trends in Theory
    and Practice of Computer Science, Springer Nature, 2026, pp. 532–546.
conference:
  end_date: 2026-02-13
  location: Krakow, Poland
  name: 'SOFSEM: Conference on Current Trends in Theory and Practice of Computer Science'
  start_date: 2026-02-09
date_created: 2026-03-01T23:01:40Z
date_published: 2026-02-13T00:00:00Z
date_updated: 2026-03-02T08:49:20Z
day: '13'
department:
- _id: HeEd
doi: 10.1007/978-3-032-17801-5_39
external_id:
  arxiv:
  - '2511.22526'
intvolume: '     16448'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2511.22526
month: '02'
oa: 1
oa_version: Preprint
page: 532-546
publication: 51st International Conference on Current Trends in Theory and Practice
  of Computer Science
publication_identifier:
  eissn:
  - 1611-3349
  isbn:
  - '9783032178008'
  issn:
  - 0302-9743
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Edge-constrained Hamiltonian paths on a point set
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 16448
year: '2026'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '21407'
abstract:
- lang: eng
  text: "This note proves that only a linear number of holes in a Cech complex of
    n points in R^d\r\ncan persist over an interval of constant length. Specifically,
    for any fixed dimension p <\r\nd and fixed ε > 0, the number of p-dimensional
    holes in the ˇ Cech complex at radius 1\r\nthat persist to radius 1+ε is bounded
    above by a constant times n,where n is the number\r\nof points. The proof uses
    a packing argument supported by relating theCˇ ech complexes\r\nwith corresponding
    snap complexes over the cells in a partition of space. The argument\r\nis self-contained
    and elementary, relying on geometric and combinatorial constructions\r\nrather
    than on the existing theory of sparse approximations or interleavings. The bound\r\nalso
    applies to Alpha complexes and Vietoris–Rips complexes. While our result can be\r\ninferred
    from prior work on sparse filtrations, to our knowledge, no explicit statement\r\nor
    direct proof of this bound appears in the literature."
acknowledgement: The authors would like to thank Michael Lesnick and Primoz Skraba
  for their helpful comments regarding sparse approximations of filtrations. We are
  also grateful to the anonymous referees for their careful reading and constructive
  suggestions. The three authors are supported by the Wittgenstein Prize, Austrian
  Science Fund (FWF), grant no. Z 342-N31, by the DFG Collaborative Research Center
  TRR 109, Austrian Science Fund (FWF), grant no. I 02979-N35, the U.S. National Science
  Foundation (NSF-DMS), grant no. 2005630, and a JSPS Grant-in-Aid for Transformative
  Research Areas (A) (22H05107, Y.H.), EPSRC Research Grant EP/Y008642/1.
article_number: '5'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Matthew
  full_name: Kahle, Matthew
  last_name: Kahle
- first_name: Shu
  full_name: Kanazawa, Shu
  last_name: Kanazawa
citation:
  ama: Edelsbrunner H, Kahle M, Kanazawa S. Maximum persistent Betti numbers of Čech
    complexes. <i>Journal of Applied and Computational Topology</i>. 2026;10. doi:<a
    href="https://doi.org/10.1007/s41468-026-00233-3">10.1007/s41468-026-00233-3</a>
  apa: Edelsbrunner, H., Kahle, M., &#38; Kanazawa, S. (2026). Maximum persistent
    Betti numbers of Čech complexes. <i>Journal of Applied and Computational Topology</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s41468-026-00233-3">https://doi.org/10.1007/s41468-026-00233-3</a>
  chicago: Edelsbrunner, Herbert, Matthew Kahle, and Shu Kanazawa. “Maximum Persistent
    Betti Numbers of Čech Complexes.” <i>Journal of Applied and Computational Topology</i>.
    Springer Nature, 2026. <a href="https://doi.org/10.1007/s41468-026-00233-3">https://doi.org/10.1007/s41468-026-00233-3</a>.
  ieee: H. Edelsbrunner, M. Kahle, and S. Kanazawa, “Maximum persistent Betti numbers
    of Čech complexes,” <i>Journal of Applied and Computational Topology</i>, vol.
    10. Springer Nature, 2026.
  ista: Edelsbrunner H, Kahle M, Kanazawa S. 2026. Maximum persistent Betti numbers
    of Čech complexes. Journal of Applied and Computational Topology. 10, 5.
  mla: Edelsbrunner, Herbert, et al. “Maximum Persistent Betti Numbers of Čech Complexes.”
    <i>Journal of Applied and Computational Topology</i>, vol. 10, 5, Springer Nature,
    2026, doi:<a href="https://doi.org/10.1007/s41468-026-00233-3">10.1007/s41468-026-00233-3</a>.
  short: H. Edelsbrunner, M. Kahle, S. Kanazawa, Journal of Applied and Computational
    Topology 10 (2026).
date_created: 2026-03-08T23:01:45Z
date_published: 2026-03-01T00:00:00Z
date_updated: 2026-03-09T11:31:29Z
day: '01'
ddc:
- '500'
department:
- _id: HeEd
doi: 10.1007/s41468-026-00233-3
external_id:
  arxiv:
  - '2409.05241'
file:
- access_level: open_access
  checksum: 0bf6dc430cafa40c08f260fe17d54595
  content_type: application/pdf
  creator: dernst
  date_created: 2026-03-09T11:29:30Z
  date_updated: 2026-03-09T11:29:30Z
  file_id: '21416'
  file_name: 2026_JourAppliedCompTopology_Edelsbrunner.pdf
  file_size: 323111
  relation: main_file
  success: 1
file_date_updated: 2026-03-09T11:29:30Z
has_accepted_license: '1'
intvolume: '        10'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
project:
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Journal of Applied and Computational Topology
publication_identifier:
  eissn:
  - 2367-1734
  issn:
  - 2367-1726
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Maximum persistent Betti numbers of Čech complexes
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '21410'
abstract:
- lang: eng
  text: Given a finite set of red and blue points in R^d, the MST-ratio is defined
    as the total length of the Euclidean minimum spanning trees of the red points
    and the blue points, divided by the length of the Euclidean minimum spanning tree
    of their union. The MST-ratio has recently gained attention due to its direct
    interpretation in topological models for studying point sets with applications
    in spatial biology. The maximum MST-ratio of a point set is the maximum MST-ratio
    over all proper colorings of its points by red and blue. We prove that finding
    the maximum MST-ratio of a given point set is NP-hard when the dimension is part
    of the input. Moreover, we present a quadratic-time 3-approximation algorithm
    for this problem. As part of the proof, we show that in any metric space, the
    maximum MST-ratio is smaller than 3. Furthermore, we study the average MST-ratio
    over all colorings of a set of n points. We show that this average is always at
    least n-2/n-1, and for n random points uniformly distributed in a d-dimensional
    unit cube, the average tends to (math formular) in expectation as n approaches
    infinity.
acknowledgement: "A. J. Ameli—Supported by the project COALESCE (ERC grant no. 853234).\r\nM.
  Saghafian—Partially supported by the European Research Council (ERC), grant no.
  788183, and by the Wittgenstein Prize, Austrian Science Fund (FWF), grant no. Z
  342-N31."
alternative_title:
- LNCS
article_processing_charge: No
arxiv: 1
author:
- first_name: Afrouz
  full_name: Jabal Ameli, Afrouz
  last_name: Jabal Ameli
- first_name: Faezeh
  full_name: Motiei, Faezeh
  last_name: Motiei
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: 'Jabal Ameli A, Motiei F, Saghafian M. On the MST-ratio: Theoretical bounds
    and complexity of finding the maximum. In: <i>20th International Conference and
    Workshops on Algorithms and Computation</i>. Vol 16444. Springer Nature; 2026:386-401.
    doi:<a href="https://doi.org/10.1007/978-981-95-7127-7_26">10.1007/978-981-95-7127-7_26</a>'
  apa: 'Jabal Ameli, A., Motiei, F., &#38; Saghafian, M. (2026). On the MST-ratio:
    Theoretical bounds and complexity of finding the maximum. In <i>20th International
    Conference and Workshops on Algorithms and Computation</i> (Vol. 16444, pp. 386–401).
    Perugia, Italy: Springer Nature. <a href="https://doi.org/10.1007/978-981-95-7127-7_26">https://doi.org/10.1007/978-981-95-7127-7_26</a>'
  chicago: 'Jabal Ameli, Afrouz, Faezeh Motiei, and Morteza Saghafian. “On the MST-Ratio:
    Theoretical Bounds and Complexity of Finding the Maximum.” In <i>20th International
    Conference and Workshops on Algorithms and Computation</i>, 16444:386–401. Springer
    Nature, 2026. <a href="https://doi.org/10.1007/978-981-95-7127-7_26">https://doi.org/10.1007/978-981-95-7127-7_26</a>.'
  ieee: 'A. Jabal Ameli, F. Motiei, and M. Saghafian, “On the MST-ratio: Theoretical
    bounds and complexity of finding the maximum,” in <i>20th International Conference
    and Workshops on Algorithms and Computation</i>, Perugia, Italy, 2026, vol. 16444,
    pp. 386–401.'
  ista: 'Jabal Ameli A, Motiei F, Saghafian M. 2026. On the MST-ratio: Theoretical
    bounds and complexity of finding the maximum. 20th International Conference and
    Workshops on Algorithms and Computation. WALCOM: International Conference and
    Workshops on Algorithms and Computation, LNCS, vol. 16444, 386–401.'
  mla: 'Jabal Ameli, Afrouz, et al. “On the MST-Ratio: Theoretical Bounds and Complexity
    of Finding the Maximum.” <i>20th International Conference and Workshops on Algorithms
    and Computation</i>, vol. 16444, Springer Nature, 2026, pp. 386–401, doi:<a href="https://doi.org/10.1007/978-981-95-7127-7_26">10.1007/978-981-95-7127-7_26</a>.'
  short: A. Jabal Ameli, F. Motiei, M. Saghafian, in:, 20th International Conference
    and Workshops on Algorithms and Computation, Springer Nature, 2026, pp. 386–401.
conference:
  end_date: 2026-03-06
  location: Perugia, Italy
  name: 'WALCOM: International Conference and Workshops on Algorithms and Computation'
  start_date: 2026-03-04
date_created: 2026-03-08T23:01:45Z
date_published: 2026-02-14T00:00:00Z
date_updated: 2026-03-09T10:25:41Z
day: '14'
department:
- _id: HeEd
doi: 10.1007/978-981-95-7127-7_26
ec_funded: 1
external_id:
  arxiv:
  - '2409.11079'
intvolume: '     16444'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2409.11079
month: '02'
oa: 1
oa_version: Preprint
page: 386-401
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
publication: 20th International Conference and Workshops on Algorithms and Computation
publication_identifier:
  eissn:
  - 1611-3349
  isbn:
  - '9789819571260'
  issn:
  - 0302-9743
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'On the MST-ratio: Theoretical bounds and complexity of finding the maximum'
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 16444
year: '2026'
...
---
OA_place: publisher
_id: '21021'
abstract:
- lang: eng
  text: This thesis examines how geometry and topology intersect in the representation,
    transformation, and analysis of complex shapes. It considers how continuous manifolds
    relate to their discrete analogues, how topological structures evolve in persistence
    vineyards, and how tools from topological data analysis can illuminate problems
    in mathematical physics. Central to this exploration is the question of how structure,
    both geometric and topological, persists or changes under approximation, sampling,
    or deformation. The work develops new approaches to skeletal and grid-based representations
    of surfaces, reveals the full expressive capacity of persistence vineyards, and
    applies topological methods to the longstanding problem of equilibria in electrostatic
    fields. These threads braid together into a broader understanding of how topology
    and geometry inform one another across theory, computation, and application.
acknowledged_ssus:
- _id: M-Shop
- _id: ScienComp
acknowledgement: "The research presented in this thesis was funded by the DFG Collaborative
  Research\r\nCenter TRR 109, ‘Discretization in Geometry and Dynamics’.\r\n"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Christopher D
  full_name: Fillmore, Christopher D
  id: 35638A5C-AAC7-11E9-B0BF-5503E6697425
  last_name: Fillmore
citation:
  ama: Fillmore CD. Braiding geometry and topology to study shapes and data. 2026.
    doi:<a href="https://doi.org/10.15479/AT-ISTA-21021">10.15479/AT-ISTA-21021</a>
  apa: Fillmore, C. D. (2026). <i>Braiding geometry and topology to study shapes and
    data</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT-ISTA-21021">https://doi.org/10.15479/AT-ISTA-21021</a>
  chicago: Fillmore, Christopher D. “Braiding Geometry and Topology to Study Shapes
    and Data.” Institute of Science and Technology Austria, 2026. <a href="https://doi.org/10.15479/AT-ISTA-21021">https://doi.org/10.15479/AT-ISTA-21021</a>.
  ieee: C. D. Fillmore, “Braiding geometry and topology to study shapes and data,”
    Institute of Science and Technology Austria, 2026.
  ista: Fillmore CD. 2026. Braiding geometry and topology to study shapes and data.
    Institute of Science and Technology Austria.
  mla: Fillmore, Christopher D. <i>Braiding Geometry and Topology to Study Shapes
    and Data</i>. Institute of Science and Technology Austria, 2026, doi:<a href="https://doi.org/10.15479/AT-ISTA-21021">10.15479/AT-ISTA-21021</a>.
  short: C.D. Fillmore, Braiding Geometry and Topology to Study Shapes and Data, Institute
    of Science and Technology Austria, 2026.
corr_author: '1'
date_created: 2026-01-20T21:38:40Z
date_published: 2026-01-21T00:00:00Z
date_updated: 2026-04-07T11:42:49Z
day: '21'
ddc:
- '514'
- '516'
degree_awarded: PhD
department:
- _id: GradSch
- _id: HeEd
- _id: UlWa
doi: 10.15479/AT-ISTA-21021
file:
- access_level: open_access
  checksum: 4c0889130095c31d4e5088c5b8dfd607
  content_type: application/pdf
  creator: cfillmor
  date_created: 2026-01-26T19:44:46Z
  date_updated: 2026-01-30T11:40:09Z
  file_id: '21046'
  file_name: 2025_Fillmore_Christopher_Thesis.pdf
  file_size: 55954297
  relation: main_file
- access_level: closed
  checksum: d69afb71d82ab98f856886126ee7303a
  content_type: application/x-zip-compressed
  creator: cfillmor
  date_created: 2026-01-26T19:46:20Z
  date_updated: 2026-01-26T19:46:20Z
  file_id: '21047'
  file_name: Thesis.zip
  file_size: 166080788
  relation: source_file
file_date_updated: 2026-01-30T11:40:09Z
has_accepted_license: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: '122'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '20260'
    relation: part_of_dissertation
    status: public
  - id: '21050'
    relation: part_of_dissertation
    status: public
  - id: '21051'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
title: Braiding geometry and topology to study shapes and data
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2026'
...
---
OA_place: repository
_id: '21051'
abstract:
- lang: eng
  text: 'In this work, we introduce and study what we believe is an intriguing and,
    to the best of our knowledge, previously unknown connection between two areas
    in computational topology, topological data analysis (TDA) and knot theory. Given
    a function from a topological space to $\mathbb{R}$, TDA provides tools to simplify
    and study the importance of topological features: in particular, the $l^{th}$-dimensional
    persistence diagram encodes the $l$-homology in the sublevel set as the function
    value increases as a set of points in the plane. Given a continuous one-parameter
    family of such functions, we can combine the persistence diagrams into an object
    known as a vineyard, which track the evolution of points in the persistence diagram.
    If we further restrict that family of functions to be periodic, we identify the
    two ends of the vineyard, yielding a closed vineyard. This allows the study of
    monodromy, which in this context means that following the family of functions
    for a period permutes the set of points in a non-trivial way. In this work, given
    a link and value $l$, we construct a topological space and periodic family of
    functions such that the closed $l$-vineyard contains this link. This shows that
    vineyards are topologically as rich as one could possibly hope. Importantly, it
    has at least two immediate consequences: First, monodromy of any periodicity can
    occur in a $l$-vineyard, answering a variant of a question by [Arya et al 2024].
    To exhibit this, we also reformulate monodromy in a more geometric way, which
    may be of interest in itself. Second, distinguishing vineyards is likely to be
    difficult given the known difficulty of knot and link recognition, which have
    strong connections to many NP-hard problems.'
article_processing_charge: No
arxiv: 1
author:
- first_name: Erin
  full_name: ' Chambers, Erin'
  last_name: ' Chambers'
- first_name: Christopher D
  full_name: Fillmore, Christopher D
  id: 35638A5C-AAC7-11E9-B0BF-5503E6697425
  last_name: Fillmore
- first_name: Elizabeth R
  full_name: Stephenson, Elizabeth R
  id: 2D04F932-F248-11E8-B48F-1D18A9856A87
  last_name: Stephenson
  orcid: 0000-0002-6862-208X
- first_name: Mathijs
  full_name: Wintraecken, Mathijs
  id: 307CFBC8-F248-11E8-B48F-1D18A9856A87
  last_name: Wintraecken
  orcid: 0000-0002-7472-2220
citation:
  ama: Chambers E, Fillmore CD, Stephenson ER, Wintraecken M. Braiding vineyards.
    <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/ARXIV.2504.11203">10.48550/ARXIV.2504.11203</a>
  apa: Chambers, E., Fillmore, C. D., Stephenson, E. R., &#38; Wintraecken, M. (n.d.).
    Braiding vineyards. <i>arXiv</i>. <a href="https://doi.org/10.48550/ARXIV.2504.11203">https://doi.org/10.48550/ARXIV.2504.11203</a>
  chicago: Chambers, Erin, Christopher D Fillmore, Elizabeth R Stephenson, and Mathijs
    Wintraecken. “Braiding Vineyards.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/ARXIV.2504.11203">https://doi.org/10.48550/ARXIV.2504.11203</a>.
  ieee: E.  Chambers, C. D. Fillmore, E. R. Stephenson, and M. Wintraecken, “Braiding
    vineyards,” <i>arXiv</i>. .
  ista: Chambers E, Fillmore CD, Stephenson ER, Wintraecken M. Braiding vineyards.
    arXiv, <a href="https://doi.org/10.48550/ARXIV.2504.11203">10.48550/ARXIV.2504.11203</a>.
  mla: Chambers, Erin, et al. “Braiding Vineyards.” <i>ArXiv</i>, doi:<a href="https://doi.org/10.48550/ARXIV.2504.11203">10.48550/ARXIV.2504.11203</a>.
  short: E.  Chambers, C.D. Fillmore, E.R. Stephenson, M. Wintraecken, ArXiv (n.d.).
corr_author: '1'
date_created: 2026-01-27T14:41:44Z
date_published: 2026-01-02T00:00:00Z
date_updated: 2026-04-07T11:42:48Z
day: '02'
department:
- _id: HeEd
doi: 10.48550/ARXIV.2504.11203
external_id:
  arxiv:
  - '2504.11203'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2504.11203
month: '01'
oa: 1
oa_version: Preprint
publication: arXiv
publication_status: draft
related_material:
  record:
  - id: '21056'
    relation: later_version
    status: public
  - id: '21021'
    relation: dissertation_contains
    status: public
status: public
title: Braiding vineyards
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: preprint
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '21781'
abstract:
- lang: eng
  text: "Given a set A of n points (vertices) in general position in the plane, the
    complete geometric graph \r\nKn[A] consists of all (n2) segments (edges) between
    the elements of A. It is known that the edge set of every complete geometric graph
    on n vertices can be partitioned into O(n3∕2) crossing-free paths (or matchings).
    We strengthen this result under various additional assumptions on the point set.
    In particular, we prove that for a set A of n randomly selected points, uniformly
    distributed in [0,1]2, with probability tending to 1 as n→∞, the edge set of Kn[A]
    can be covered by O(nlogn) crossing-free paths and by O(n√logn) crossing-free
    matchings. On the other hand, we construct n-element point sets such that covering
    the edge set of Kn[A] requires a quadratic number of monotone paths."
acknowledgement: "Research partially supported by ERC Advanced Grant \"GeoScape\",
  no. 882971 and\r\nHungarian NKFIH grant no. K-131529. Work by the third author is
  supported by EPSRC grant\r\nEP/X013642/1. Work by the third author is partially
  supported by the European Research Council (ERC), grant no. 788183, and by the Wittgenstein
  Prize, Austrian Science Fund (FWF), grant no. Z 342-N31."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Adrian
  full_name: Dumitrescu, Adrian
  last_name: Dumitrescu
- first_name: János
  full_name: Pach, János
  last_name: Pach
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
- first_name: Alex
  full_name: Scott, Alex
  last_name: Scott
citation:
  ama: Dumitrescu A, Pach J, Saghafian M, Scott A. Covering complete geometric graphs
    by monotone paths. <i>Combinatorics and Number Theory</i>. 2026;15(1):73-82. doi:<a
    href="https://doi.org/10.2140/cnt.2026.15.73">10.2140/cnt.2026.15.73</a>
  apa: Dumitrescu, A., Pach, J., Saghafian, M., &#38; Scott, A. (2026). Covering complete
    geometric graphs by monotone paths. <i>Combinatorics and Number Theory</i>. Mathematical
    Sciences Publishers. <a href="https://doi.org/10.2140/cnt.2026.15.73">https://doi.org/10.2140/cnt.2026.15.73</a>
  chicago: Dumitrescu, Adrian, János Pach, Morteza Saghafian, and Alex Scott. “Covering
    Complete Geometric Graphs by Monotone Paths.” <i>Combinatorics and Number Theory</i>.
    Mathematical Sciences Publishers, 2026. <a href="https://doi.org/10.2140/cnt.2026.15.73">https://doi.org/10.2140/cnt.2026.15.73</a>.
  ieee: A. Dumitrescu, J. Pach, M. Saghafian, and A. Scott, “Covering complete geometric
    graphs by monotone paths,” <i>Combinatorics and Number Theory</i>, vol. 15, no.
    1. Mathematical Sciences Publishers, pp. 73–82, 2026.
  ista: Dumitrescu A, Pach J, Saghafian M, Scott A. 2026. Covering complete geometric
    graphs by monotone paths. Combinatorics and Number Theory. 15(1), 73–82.
  mla: Dumitrescu, Adrian, et al. “Covering Complete Geometric Graphs by Monotone
    Paths.” <i>Combinatorics and Number Theory</i>, vol. 15, no. 1, Mathematical Sciences
    Publishers, 2026, pp. 73–82, doi:<a href="https://doi.org/10.2140/cnt.2026.15.73">10.2140/cnt.2026.15.73</a>.
  short: A. Dumitrescu, J. Pach, M. Saghafian, A. Scott, Combinatorics and Number
    Theory 15 (2026) 73–82.
date_created: 2026-05-03T22:01:37Z
date_published: 2026-04-17T00:00:00Z
date_updated: 2026-05-07T07:45:24Z
day: '17'
department:
- _id: HeEd
doi: 10.2140/cnt.2026.15.73
ec_funded: 1
external_id:
  arxiv:
  - '2507.10840'
intvolume: '        15'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2507.10840
month: '04'
oa: 1
oa_version: Preprint
page: 73-82
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
publication: Combinatorics and Number Theory
publication_identifier:
  eissn:
  - 2996-220X
  issn:
  - 2996-2196
publication_status: published
publisher: Mathematical Sciences Publishers
quality_controlled: '1'
scopus_import: '1'
status: public
title: Covering complete geometric graphs by monotone paths
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 15
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '18626'
abstract:
- lang: eng
  text: "The local angle property of the (order-1) Delaunay triangulations of a generic
    set in R2\r\n asserts that the sum of two angles opposite a common edge is less
    than π. This paper extends this property to higher order and uses it to generalize
    two classic properties from order-1 to order-2: (1) among the complete level-2
    hypertriangulations of a generic point set in R2, the order-2 Delaunay triangulation
    lexicographically maximizes the sorted angle vector; (2) among the maximal level-2
    hypertriangulations of a generic point set in R2, the order-2 Delaunay triangulation
    is the only one that has the local angle property. We also use our method of establishing
    (2) to give a new short proof of the angle vector optimality for the (order-1)
    Delaunay triangulation. For order-1, both properties have been instrumental in
    numerous applications of Delaunay triangulations, and we expect that their generalization
    will make order-2 Delaunay triangulations more attractive to applications as well."
acknowledgement: Work by the first and third authors is partially supported by the
  European Research Council (ERC), grant no. 788183, by the Wittgenstein Prize, Austrian
  Science Fund (FWF), grant no. Z 342-N31, and by the DFG Collaborative Research Center
  TRR 109, Austrian Science Fund (FWF), grant no. I 02979-N35. Work by the second
  author is partially supported by the Alexander von Humboldt Foundation.
article_number: '110055'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Alexey
  full_name: Garber, Alexey
  last_name: Garber
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: Edelsbrunner H, Garber A, Saghafian M. Order-2 Delaunay triangulations optimize
    angles. <i>Advances in Mathematics</i>. 2025;461. doi:<a href="https://doi.org/10.1016/j.aim.2024.110055">10.1016/j.aim.2024.110055</a>
  apa: Edelsbrunner, H., Garber, A., &#38; Saghafian, M. (2025). Order-2 Delaunay
    triangulations optimize angles. <i>Advances in Mathematics</i>. Elsevier. <a href="https://doi.org/10.1016/j.aim.2024.110055">https://doi.org/10.1016/j.aim.2024.110055</a>
  chicago: Edelsbrunner, Herbert, Alexey Garber, and Morteza Saghafian. “Order-2 Delaunay
    Triangulations Optimize Angles.” <i>Advances in Mathematics</i>. Elsevier, 2025.
    <a href="https://doi.org/10.1016/j.aim.2024.110055">https://doi.org/10.1016/j.aim.2024.110055</a>.
  ieee: H. Edelsbrunner, A. Garber, and M. Saghafian, “Order-2 Delaunay triangulations
    optimize angles,” <i>Advances in Mathematics</i>, vol. 461. Elsevier, 2025.
  ista: Edelsbrunner H, Garber A, Saghafian M. 2025. Order-2 Delaunay triangulations
    optimize angles. Advances in Mathematics. 461, 110055.
  mla: Edelsbrunner, Herbert, et al. “Order-2 Delaunay Triangulations Optimize Angles.”
    <i>Advances in Mathematics</i>, vol. 461, 110055, Elsevier, 2025, doi:<a href="https://doi.org/10.1016/j.aim.2024.110055">10.1016/j.aim.2024.110055</a>.
  short: H. Edelsbrunner, A. Garber, M. Saghafian, Advances in Mathematics 461 (2025).
corr_author: '1'
date_created: 2024-12-08T23:01:54Z
date_published: 2025-02-01T00:00:00Z
date_updated: 2025-04-15T07:16:53Z
day: '01'
department:
- _id: HeEd
doi: 10.1016/j.aim.2024.110055
ec_funded: 1
external_id:
  arxiv:
  - '2310.18238'
  isi:
  - '001370682500001'
intvolume: '       461'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2310.18238
month: '02'
oa: 1
oa_version: Preprint
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Advances in Mathematics
publication_identifier:
  eissn:
  - 1090-2082
  issn:
  - 0001-8708
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Order-2 Delaunay triangulations optimize angles
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 461
year: '2025'
...
---
OA_type: closed access
_id: '19937'
abstract:
- lang: eng
  text: Simplets are elementary units within simplicial complexes and are fundamental
    for analyzing the structure of simplicial complexes. Previous efforts have mainly
    focused on accurately counting or approximating the number of simplets rather
    than studying their frequencies. However, analyzing simplet frequencies is more
    practical for large-scale simplicial complexes. This paper introduces the Simplet
    Frequency Distribution (SFD) vector, which enables the analysis of simplet frequencies
    in simplicial complexes. Additionally, we provide a bound on the sample complexity
    required to approximate the SFD vector using any uniform sampling-based algorithm
    accurately. We extend the definition of simplet frequency distribution to encompass
    simplices, allowing for the analysis of simplet frequencies within simplices of
    simplicial complexes. This paper introduces the Simplet Degree Vector (SDV) and
    the Simplet Degree Centrality (SDC), facilitating this analysis for each simplex.
    Furthermore, we present a bound on the sample complexity required for accurately
    approximating the SDV and SDC for a set of simplices using any uniform sampling-based
    algorithm. We also introduce algorithms for approximating SFD, geometric SFD,
    SDV, and SDC. We also validate the theoretical bounds with experiments on random
    simplicial complexes and demonstrate the practical application through a case
    study.
acknowledgement: "The authors would like to thank the anonymous reviewers for their
  valuable comments and suggestions, which improved this paper.\r\nWork by the first
  and fourth authors is partially supported by the European Research Council (ERC),
  grant no. 788183, by the Wittgenstein Prize, Austrian Science Fund (FWF), grant
  no. Z 342-N31, and by the DFG Collaborative Research Center TRR 109, Austrian Science
  Fund (FWF), grant no. I 02979-N35."
article_number: '122425'
article_processing_charge: No
article_type: original
author:
- first_name: Mohammad
  full_name: Mahini, Mohammad
  last_name: Mahini
- first_name: Hamid
  full_name: Beigy, Hamid
  last_name: Beigy
- first_name: Salman
  full_name: Qadami, Salman
  last_name: Qadami
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: 'Mahini M, Beigy H, Qadami S, Saghafian M. Simplet-based signatures and approximation
    in simplicial complexes: Frequency, degree, and centrality. <i>Information Sciences</i>.
    2025;719(11). doi:<a href="https://doi.org/10.1016/j.ins.2025.122425">10.1016/j.ins.2025.122425</a>'
  apa: 'Mahini, M., Beigy, H., Qadami, S., &#38; Saghafian, M. (2025). Simplet-based
    signatures and approximation in simplicial complexes: Frequency, degree, and centrality.
    <i>Information Sciences</i>. Elsevier. <a href="https://doi.org/10.1016/j.ins.2025.122425">https://doi.org/10.1016/j.ins.2025.122425</a>'
  chicago: 'Mahini, Mohammad, Hamid Beigy, Salman Qadami, and Morteza Saghafian. “Simplet-Based
    Signatures and Approximation in Simplicial Complexes: Frequency, Degree, and Centrality.”
    <i>Information Sciences</i>. Elsevier, 2025. <a href="https://doi.org/10.1016/j.ins.2025.122425">https://doi.org/10.1016/j.ins.2025.122425</a>.'
  ieee: 'M. Mahini, H. Beigy, S. Qadami, and M. Saghafian, “Simplet-based signatures
    and approximation in simplicial complexes: Frequency, degree, and centrality,”
    <i>Information Sciences</i>, vol. 719, no. 11. Elsevier, 2025.'
  ista: 'Mahini M, Beigy H, Qadami S, Saghafian M. 2025. Simplet-based signatures
    and approximation in simplicial complexes: Frequency, degree, and centrality.
    Information Sciences. 719(11), 122425.'
  mla: 'Mahini, Mohammad, et al. “Simplet-Based Signatures and Approximation in Simplicial
    Complexes: Frequency, Degree, and Centrality.” <i>Information Sciences</i>, vol.
    719, no. 11, 122425, Elsevier, 2025, doi:<a href="https://doi.org/10.1016/j.ins.2025.122425">10.1016/j.ins.2025.122425</a>.'
  short: M. Mahini, H. Beigy, S. Qadami, M. Saghafian, Information Sciences 719 (2025).
corr_author: '1'
date_created: 2025-06-30T08:48:48Z
date_published: 2025-11-01T00:00:00Z
date_updated: 2025-12-30T09:05:32Z
day: '01'
department:
- _id: HeEd
doi: 10.1016/j.ins.2025.122425
ec_funded: 1
external_id:
  isi:
  - '001516170500002'
intvolume: '       719'
isi: 1
issue: '11'
language:
- iso: eng
month: '11'
oa_version: None
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Information Sciences
publication_identifier:
  issn:
  - 0020-0255
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Simplet-based signatures and approximation in simplicial complexes: Frequency,
  degree, and centrality'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 719
year: '2025'
...
---
OA_place: publisher
OA_type: gold
_id: '20005'
abstract:
- lang: eng
  text: "We generalize a classical result by Boris Delaunay that introduced Delaunay
    triangulations. In particular, we prove that for a locally finite and coarsely
    dense generic point set A in ℝ^d, every generic point of ℝ^d belongs to exactly
    binom(d+k,d) simplices whose vertices belong to A and whose circumspheres enclose
    exactly k points of A. We extend this result to the cases in which the points
    are weighted, and when A contains only finitely many points in ℝ^d or in \U0001D54A^d.
    Furthermore, we use the result to give a new geometric proof for the fact that
    volumes of hypersimplices are Eulerian numbers."
acknowledgement: "Herbert Edelsbrunner: partially supported by the Wittgenstein Prize,
  Austrian Science\r\nFund (FWF), grant no. Z 342-N31, and by the DFG Collaborative
  Research Center TRR 109,\r\nAustrian Science Fund (FWF), grant no. I 02979-N35.\r\nAlexey
  Garber: partially supported by the Simons Foundation.\r\nMorteza Saghafian: partially
  supported by the Wittgenstein Prize, Austrian Science Fund (FWF),\r\ngrant no. Z
  342-N31, and by the DFG Collaborative Research Center TRR 109, Austrian Science\r\nFund
  (FWF), grant no. I 02979-N35"
alternative_title:
- LIPIcs
article_number: '43'
article_processing_charge: Yes
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Alexey
  full_name: Garber, Alexey
  last_name: Garber
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: 'Edelsbrunner H, Garber A, Saghafian M. On spheres with k points inside. In:
    <i>41st International Symposium on Computational Geometry</i>. Vol 332. Schloss
    Dagstuhl - Leibniz-Zentrum für Informatik; 2025. doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.43">10.4230/LIPIcs.SoCG.2025.43</a>'
  apa: 'Edelsbrunner, H., Garber, A., &#38; Saghafian, M. (2025). On spheres with
    k points inside. In <i>41st International Symposium on Computational Geometry</i>
    (Vol. 332). Kanazawa, Japan: Schloss Dagstuhl - Leibniz-Zentrum für Informatik.
    <a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.43">https://doi.org/10.4230/LIPIcs.SoCG.2025.43</a>'
  chicago: Edelsbrunner, Herbert, Alexey Garber, and Morteza Saghafian. “On Spheres
    with k Points Inside.” In <i>41st International Symposium on Computational Geometry</i>,
    Vol. 332. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2025. <a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.43">https://doi.org/10.4230/LIPIcs.SoCG.2025.43</a>.
  ieee: H. Edelsbrunner, A. Garber, and M. Saghafian, “On spheres with k points inside,”
    in <i>41st International Symposium on Computational Geometry</i>, Kanazawa, Japan,
    2025, vol. 332.
  ista: 'Edelsbrunner H, Garber A, Saghafian M. 2025. On spheres with k points inside.
    41st International Symposium on Computational Geometry. SoCG: Symposium on Computational
    Geometry, LIPIcs, vol. 332, 43.'
  mla: Edelsbrunner, Herbert, et al. “On Spheres with k Points Inside.” <i>41st International
    Symposium on Computational Geometry</i>, vol. 332, 43, Schloss Dagstuhl - Leibniz-Zentrum
    für Informatik, 2025, doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.43">10.4230/LIPIcs.SoCG.2025.43</a>.
  short: H. Edelsbrunner, A. Garber, M. Saghafian, in:, 41st International Symposium
    on Computational Geometry, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2025.
conference:
  end_date: 2025-06-27
  location: Kanazawa, Japan
  name: 'SoCG: Symposium on Computational Geometry'
  start_date: 2025-06-23
corr_author: '1'
date_created: 2025-07-13T22:01:22Z
date_published: 2025-06-20T00:00:00Z
date_updated: 2025-07-14T07:26:14Z
day: '20'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.4230/LIPIcs.SoCG.2025.43
external_id:
  arxiv:
  - '2410.21204'
file:
- access_level: open_access
  checksum: b5313ed8575ea87913c71a6e3c7513c8
  content_type: application/pdf
  creator: dernst
  date_created: 2025-07-14T07:24:22Z
  date_updated: 2025-07-14T07:24:22Z
  file_id: '20016'
  file_name: 2025_LIPIcs.SoCG_Edelsbrunner.pdf
  file_size: 661893
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  success: 1
file_date_updated: 2025-07-14T07:24:22Z
has_accepted_license: '1'
intvolume: '       332'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: 41st International Symposium on Computational Geometry
publication_identifier:
  eissn:
  - 1868-8969
  isbn:
  - '9783959773706'
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: On spheres with k points inside
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 332
year: '2025'
...
---
OA_place: publisher
OA_type: gold
_id: '20006'
abstract:
- lang: eng
  text: In numerous fields, dynamic time series data require continuous updates, necessitating
    efficient data processing techniques for accurate analysis. This paper examines
    the banana tree data structure, specifically designed to efficiently maintain
    the multi-scale topological descriptor commonly known as persistent homology for
    dynamically changing time series data. We implement this data structure and conduct
    an experimental study to assess its properties and runtime for update operations.
    Our findings indicate that banana trees are highly effective with unbiased random
    data, outperforming state-of-the-art static algorithms in these scenarios. Additionally,
    our results show that real-world time series share structural properties with
    unbiased random walks, suggesting potential practical utility for our implementation.
acknowledgement: "Lara Ost: Supported by the Vienna Graduate School on Computational
  Optimization\r\n(VGSCO), FWF project no. W1260-N35.\r\nSebastiano Cultrera di Montesano:
  Supported by the Eric and Wendy Schmidt Center at the Broad Institute of MIT and
  Harvard.\r\nHerbert Edelsbrunner: Partially supported by the Wittgenstein Prize,
  FWF grant no. Z 342-N31,\r\nand by the DFG Collaborative Research Center TRR 109,
  FWF grant no. I 02979-N35."
alternative_title:
- LIPIcs
article_number: '71'
article_processing_charge: Yes
arxiv: 1
author:
- first_name: Lara
  full_name: Ost, Lara
  last_name: Ost
- first_name: Sebastiano
  full_name: Cultrera di Montesano, Sebastiano
  id: 34D2A09C-F248-11E8-B48F-1D18A9856A87
  last_name: Cultrera di Montesano
  orcid: 0000-0001-6249-0832
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
citation:
  ama: 'Ost L, Cultrera di Montesano S, Edelsbrunner H. Banana trees for the persistence
    in time series experimentally. In: <i>41st International Symposium on Computational
    Geometry</i>. Vol 332. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2025.
    doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.71">10.4230/LIPIcs.SoCG.2025.71</a>'
  apa: 'Ost, L., Cultrera di Montesano, S., &#38; Edelsbrunner, H. (2025). Banana
    trees for the persistence in time series experimentally. In <i>41st International
    Symposium on Computational Geometry</i> (Vol. 332). Kanazawa, Japan: Schloss Dagstuhl
    - Leibniz-Zentrum für Informatik. <a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.71">https://doi.org/10.4230/LIPIcs.SoCG.2025.71</a>'
  chicago: Ost, Lara, Sebastiano Cultrera di Montesano, and Herbert Edelsbrunner.
    “Banana Trees for the Persistence in Time Series Experimentally.” In <i>41st International
    Symposium on Computational Geometry</i>, Vol. 332. Schloss Dagstuhl - Leibniz-Zentrum
    für Informatik, 2025. <a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.71">https://doi.org/10.4230/LIPIcs.SoCG.2025.71</a>.
  ieee: L. Ost, S. Cultrera di Montesano, and H. Edelsbrunner, “Banana trees for the
    persistence in time series experimentally,” in <i>41st International Symposium
    on Computational Geometry</i>, Kanazawa, Japan, 2025, vol. 332.
  ista: 'Ost L, Cultrera di Montesano S, Edelsbrunner H. 2025. Banana trees for the
    persistence in time series experimentally. 41st International Symposium on Computational
    Geometry. SoCG: Symposium on Computational Geometry, LIPIcs, vol. 332, 71.'
  mla: Ost, Lara, et al. “Banana Trees for the Persistence in Time Series Experimentally.”
    <i>41st International Symposium on Computational Geometry</i>, vol. 332, 71, Schloss
    Dagstuhl - Leibniz-Zentrum für Informatik, 2025, doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2025.71">10.4230/LIPIcs.SoCG.2025.71</a>.
  short: L. Ost, S. Cultrera di Montesano, H. Edelsbrunner, in:, 41st International
    Symposium on Computational Geometry, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2025.
conference:
  end_date: 2025-06-27
  location: Kanazawa, Japan
  name: 'SoCG: Symposium on Computational Geometry'
  start_date: 2025-06-23
corr_author: '1'
date_created: 2025-07-13T22:01:22Z
date_published: 2025-06-20T00:00:00Z
date_updated: 2025-12-30T11:04:33Z
day: '20'
ddc:
- '000'
department:
- _id: HeEd
doi: 10.4230/LIPIcs.SoCG.2025.71
external_id:
  arxiv:
  - '2405.17920'
file:
- access_level: open_access
  checksum: 3a4a7a707a56e0cfdf51428782dee55a
  content_type: application/pdf
  creator: dernst
  date_created: 2025-07-14T08:23:38Z
  date_updated: 2025-07-14T08:23:38Z
  file_id: '20017'
  file_name: 2025_LIPIcs.SoCG_Ost.pdf
  file_size: 834623
  relation: main_file
  success: 1
file_date_updated: 2025-07-14T08:23:38Z
has_accepted_license: '1'
intvolume: '       332'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 9B9290DE-BA93-11EA-9121-9846C619BF3A
  grant_number: W1260-N35
  name: Vienna Graduate School on Computational Optimization
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
publication: 41st International Symposium on Computational Geometry
publication_identifier:
  eissn:
  - 1868-8969
  isbn:
  - '9783959773706'
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
related_material:
  link:
  - relation: software
    url: https://github.com/laraost/BananaPersist
scopus_import: '1'
status: public
title: Banana trees for the persistence in time series experimentally
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 332
year: '2025'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
PlanS_conform: '1'
_id: '20293'
abstract:
- lang: eng
  text: Motivated by questions arising at the intersection of information theory and
    geometry, we compare two dissimilarity measures between finite categorical distributions.
    One is the well-known Jensen–Shannon divergence, which is easy to compute and
    whose square root is a proper metric. The other is what we call the minmax divergence,
    which is harder to compute. Just like the Jensen–Shannon divergence, it arises
    naturally from the Kullback–Leibler divergence. The main contribution of this
    paper is a proof showing that the minmax divergence can be tightly approximated
    by the Jensen–Shannon divergence. The bounds suggest that the square root of the
    minmax divergence is a metric, and we prove that this is indeed true in the one-dimensional
    case. The general case remains open. Finally, we consider analogous questions
    in the context of another Bregman divergence and the corresponding Burbea–Rao
    (Jensen–Bregman) divergence.
acknowledgement: "This research received partial funding from the European Research
  Council (ERC) under\r\nthe European Union’s Horizon 2020 research and innovation
  programme, grant no. 788183, the\r\nWittgenstein Prize, Austrian Science Fund (FWF),
  grant no. Z 342-N31, the DFG Collaborative\r\nResearch Center TRR 109, ‘Discretization
  in Geometry and Dynamics’, Austrian Science Fund (FWF), grant no. I 02979-N35, and
  the 2022 Google Research Scholar Award for project ‘Algorithms for Topological Analysis
  of Neural Networks’. The APC was waived."
article_number: '854'
article_processing_charge: Yes
article_type: original
author:
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Ziga
  full_name: Virk, Ziga
  id: 2E36B656-F248-11E8-B48F-1D18A9856A87
  last_name: Virk
- first_name: Hubert
  full_name: Wagner, Hubert
  id: 379CA8B8-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
citation:
  ama: Akopyan A, Edelsbrunner H, Virk Z, Wagner H. Tight bounds between the Jensen–Shannon
    divergence and the minmax divergence. <i>Entropy</i>. 2025;27(8). doi:<a href="https://doi.org/10.3390/e27080854">10.3390/e27080854</a>
  apa: Akopyan, A., Edelsbrunner, H., Virk, Z., &#38; Wagner, H. (2025). Tight bounds
    between the Jensen–Shannon divergence and the minmax divergence. <i>Entropy</i>.
    MDPI. <a href="https://doi.org/10.3390/e27080854">https://doi.org/10.3390/e27080854</a>
  chicago: Akopyan, Arseniy, Herbert Edelsbrunner, Ziga Virk, and Hubert Wagner. “Tight
    Bounds between the Jensen–Shannon Divergence and the Minmax Divergence.” <i>Entropy</i>.
    MDPI, 2025. <a href="https://doi.org/10.3390/e27080854">https://doi.org/10.3390/e27080854</a>.
  ieee: A. Akopyan, H. Edelsbrunner, Z. Virk, and H. Wagner, “Tight bounds between
    the Jensen–Shannon divergence and the minmax divergence,” <i>Entropy</i>, vol.
    27, no. 8. MDPI, 2025.
  ista: Akopyan A, Edelsbrunner H, Virk Z, Wagner H. 2025. Tight bounds between the
    Jensen–Shannon divergence and the minmax divergence. Entropy. 27(8), 854.
  mla: Akopyan, Arseniy, et al. “Tight Bounds between the Jensen–Shannon Divergence
    and the Minmax Divergence.” <i>Entropy</i>, vol. 27, no. 8, 854, MDPI, 2025, doi:<a
    href="https://doi.org/10.3390/e27080854">10.3390/e27080854</a>.
  short: A. Akopyan, H. Edelsbrunner, Z. Virk, H. Wagner, Entropy 27 (2025).
corr_author: '1'
date_created: 2025-09-07T22:01:33Z
date_published: 2025-08-01T00:00:00Z
date_updated: 2025-09-30T14:32:31Z
day: '01'
ddc:
- '500'
department:
- _id: HeEd
doi: 10.3390/e27080854
ec_funded: 1
external_id:
  isi:
  - '001557476000001'
  pmid:
  - '40870326'
file:
- access_level: open_access
  checksum: 65c5399c4015d9c8abb8c7a96f3d7836
  content_type: application/pdf
  creator: dernst
  date_created: 2025-09-08T07:55:48Z
  date_updated: 2025-09-08T07:55:48Z
  file_id: '20309'
  file_name: 2025_Entropy_Akopyan.pdf
  file_size: 379340
  relation: main_file
  success: 1
file_date_updated: 2025-09-08T07:55:48Z
has_accepted_license: '1'
intvolume: '        27'
isi: 1
issue: '8'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
pmid: 1
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Entropy
publication_identifier:
  eissn:
  - 1099-4300
publication_status: published
publisher: MDPI
quality_controlled: '1'
scopus_import: '1'
status: public
title: Tight bounds between the Jensen–Shannon divergence and the minmax divergence
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 27
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '20323'
abstract:
- lang: eng
  text: We establish several results combining discrete Morse theory and microlocal
    sheaf theory in the setting of finite posets and simplicial complexes. Our primary
    tool is a computationally tractable description of the bounded derived category
    of sheaves on a poset with the Alexandrov topology. We prove that each bounded
    complex of sheaves on a finite poset admits a unique (up to isomorphism of complexes)
    minimal injective resolution, and we provide algorithms for computing minimal
    injective resolution of an injective complex, as well as several useful functors
    between derived categories of sheaves. For the constant sheaf on a simplicial
    complex, we give asymptotically tight bounds on the complexity of computing the
    minimal injective resolution using those algorithms. Our main result is a novel
    definition of the discrete microsupport of a bounded complex of sheaves on a finite
    poset. We detail several foundational properties of the discrete microsupport,
    as well as a microlocal generalization of the discrete homological Morse theorem
    and Morse inequalities.
acknowledgement: This project has received funding from the European Research Council
  (ERC) under the European Union’s Horizon 2020 research and innovation programme,
  grant no. 788183, from the Wittgenstein Prize, Austrian Science Fund (FWF), grant
  no. Z342-N31, and from the DFG Collaborative Research Center TRR 109, ‘Discretization
  in Geometry and Dynamics’, Austrian Science Fund (FWF), grant no. I 02979-N35
article_number: '108068'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Adam
  full_name: Brown, Adam
  id: 70B7FDF6-608D-11E9-9333-8535E6697425
  last_name: Brown
- first_name: Ondrej
  full_name: Draganov, Ondrej
  id: 2B23F01E-F248-11E8-B48F-1D18A9856A87
  last_name: Draganov
  orcid: 0000-0003-0464-3823
citation:
  ama: Brown A, Draganov O. Discrete microlocal Morse theory. <i>Journal of Pure and
    Applied Algebra</i>. 2025;229(10). doi:<a href="https://doi.org/10.1016/j.jpaa.2025.108068">10.1016/j.jpaa.2025.108068</a>
  apa: Brown, A., &#38; Draganov, O. (2025). Discrete microlocal Morse theory. <i>Journal
    of Pure and Applied Algebra</i>. Elsevier. <a href="https://doi.org/10.1016/j.jpaa.2025.108068">https://doi.org/10.1016/j.jpaa.2025.108068</a>
  chicago: Brown, Adam, and Ondrej Draganov. “Discrete Microlocal Morse Theory.” <i>Journal
    of Pure and Applied Algebra</i>. Elsevier, 2025. <a href="https://doi.org/10.1016/j.jpaa.2025.108068">https://doi.org/10.1016/j.jpaa.2025.108068</a>.
  ieee: A. Brown and O. Draganov, “Discrete microlocal Morse theory,” <i>Journal of
    Pure and Applied Algebra</i>, vol. 229, no. 10. Elsevier, 2025.
  ista: Brown A, Draganov O. 2025. Discrete microlocal Morse theory. Journal of Pure
    and Applied Algebra. 229(10), 108068.
  mla: Brown, Adam, and Ondrej Draganov. “Discrete Microlocal Morse Theory.” <i>Journal
    of Pure and Applied Algebra</i>, vol. 229, no. 10, 108068, Elsevier, 2025, doi:<a
    href="https://doi.org/10.1016/j.jpaa.2025.108068">10.1016/j.jpaa.2025.108068</a>.
  short: A. Brown, O. Draganov, Journal of Pure and Applied Algebra 229 (2025).
corr_author: '1'
date_created: 2025-09-10T05:40:09Z
date_published: 2025-10-01T00:00:00Z
date_updated: 2025-12-30T07:55:21Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1016/j.jpaa.2025.108068
ec_funded: 1
external_id:
  arxiv:
  - '2209.14993'
file:
- access_level: open_access
  checksum: 39bcad462278c9322ef810af7db67f56
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  creator: dernst
  date_created: 2025-12-30T07:55:08Z
  date_updated: 2025-12-30T07:55:08Z
  file_id: '20886'
  file_name: 2025_JourPureAppliedAlgebra_Brown.pdf
  file_size: 3090836
  relation: main_file
  success: 1
file_date_updated: 2025-12-30T07:55:08Z
has_accepted_license: '1'
intvolume: '       229'
issue: '10'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Journal of Pure and Applied Algebra
publication_identifier:
  issn:
  - 0022-4049
publication_status: published
publisher: Elsevier
quality_controlled: '1'
related_material:
  record:
  - id: '18981'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Discrete microlocal Morse theory
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 229
year: '2025'
...
---
OA_place: repository
OA_type: green
_id: '20490'
abstract:
- lang: eng
  text: "We study flips in hypertriangulations of planar points sets. Here a level-k
    hypertriangulation of n\r\n points in the plane is a subdivision induced by the
    projection of a k-hypersimplex, which is the convex hull of the barycenters of
    the (k-1)-dimensional faces of the standard (n-1)-simplex. In particular, we introduce
    four types of flips and prove that the level-2 hypertriangulations are connected
    by these flips.\r\n"
acknowledgement: Work by all authors but the second is supported by the European Research
  Council (ERC), grant no. 788183, by the Wittgenstein Prize, Austrian Science Fund
  (FWF), grant no. Z 342-N31, and by the DFG Collaborative Research Center TRR 109,
  Austrian Science Fund (FWF), grant no. I 02979-N35. Work by the second author is
  partially supported by the Alexander von Humboldt Foundation and by the Simons Foundation
  . The second author thanks Jesús A. De Loera for useful discussions on flips and
  non-flips and Pavel Galashin and Alexey Balitskiy for useful discussions on plabic
  graphs.
article_number: '104248'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Alexey
  full_name: Garber, Alexey
  last_name: Garber
- first_name: Mohadese
  full_name: Ghafari, Mohadese
  last_name: Ghafari
- first_name: Teresa
  full_name: Heiss, Teresa
  id: 4879BB4E-F248-11E8-B48F-1D18A9856A87
  last_name: Heiss
  orcid: 0000-0002-1780-2689
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: Edelsbrunner H, Garber A, Ghafari M, Heiss T, Saghafian M. Flips in two-dimensional
    hypertriangulations. <i>European Journal of Combinatorics</i>. 2025;132. doi:<a
    href="https://doi.org/10.1016/j.ejc.2025.104248">10.1016/j.ejc.2025.104248</a>
  apa: Edelsbrunner, H., Garber, A., Ghafari, M., Heiss, T., &#38; Saghafian, M. (2025).
    Flips in two-dimensional hypertriangulations. <i>European Journal of Combinatorics</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.ejc.2025.104248">https://doi.org/10.1016/j.ejc.2025.104248</a>
  chicago: Edelsbrunner, Herbert, Alexey Garber, Mohadese Ghafari, Teresa Heiss, and
    Morteza Saghafian. “Flips in Two-Dimensional Hypertriangulations.” <i>European
    Journal of Combinatorics</i>. Elsevier, 2025. <a href="https://doi.org/10.1016/j.ejc.2025.104248">https://doi.org/10.1016/j.ejc.2025.104248</a>.
  ieee: H. Edelsbrunner, A. Garber, M. Ghafari, T. Heiss, and M. Saghafian, “Flips
    in two-dimensional hypertriangulations,” <i>European Journal of Combinatorics</i>,
    vol. 132. Elsevier, 2025.
  ista: Edelsbrunner H, Garber A, Ghafari M, Heiss T, Saghafian M. 2025. Flips in
    two-dimensional hypertriangulations. European Journal of Combinatorics. 132, 104248.
  mla: Edelsbrunner, Herbert, et al. “Flips in Two-Dimensional Hypertriangulations.”
    <i>European Journal of Combinatorics</i>, vol. 132, 104248, Elsevier, 2025, doi:<a
    href="https://doi.org/10.1016/j.ejc.2025.104248">10.1016/j.ejc.2025.104248</a>.
  short: H. Edelsbrunner, A. Garber, M. Ghafari, T. Heiss, M. Saghafian, European
    Journal of Combinatorics 132 (2025).
corr_author: '1'
date_created: 2025-10-19T22:01:31Z
date_published: 2025-10-10T00:00:00Z
date_updated: 2025-12-01T12:57:29Z
day: '10'
department:
- _id: HeEd
doi: 10.1016/j.ejc.2025.104248
ec_funded: 1
external_id:
  arxiv:
  - '2212.11380'
  isi:
  - '001599061500002'
intvolume: '       132'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2212.11380
month: '10'
oa: 1
oa_version: Preprint
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: European Journal of Combinatorics
publication_identifier:
  issn:
  - 0195-6698
publication_status: epub_ahead
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Flips in two-dimensional hypertriangulations
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 132
year: '2025'
...
---
OA_place: repository
OA_type: green
_id: '20585'
abstract:
- lang: eng
  text: Motivated by applications in medical sciences, we study finite chromatic sets
    in Euclidean space from a topological perspective. Based on the persistent homology
    for images, kernels and cokernels, we design provably stable homological quantifiers
    that describe the geometric micro- and macro-structure of how the color classes
    mingle. These can be efficiently computed using chromatic variants of Delaunay
    and alpha complexes, and code that does these computations is provided.
acknowledgement: "This project has received funding from the European Research\r\nCouncil
  (ERC) under the European Union’s Horizon 2020 research and innovation\r\nprogramme,
  grant no. 788183, from the Wittgenstein Prize, Austrian Science Fund\r\n(FWF), grant
  no. Z 342-N31, and from the DFG Collaborative Research Center TRR\r\n109, ‘Discretization
  in Geometry and Dynamics’, Austrian Science Fund (FWF),\r\ngrant no. I 02979-N35."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Sebastiano
  full_name: Cultrera di Montesano, Sebastiano
  id: 34D2A09C-F248-11E8-B48F-1D18A9856A87
  last_name: Cultrera di Montesano
  orcid: 0000-0001-6249-0832
- first_name: Ondrej
  full_name: Draganov, Ondrej
  id: 2B23F01E-F248-11E8-B48F-1D18A9856A87
  last_name: Draganov
  orcid: 0000-0003-0464-3823
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Morteza
  full_name: Saghafian, Morteza
  id: f86f7148-b140-11ec-9577-95435b8df824
  last_name: Saghafian
citation:
  ama: Cultrera di Montesano S, Draganov O, Edelsbrunner H, Saghafian M. Chromatic
    alpha complexes. <i>Foundations of Data Science</i>. 2025;8:30-62. doi:<a href="https://doi.org/10.3934/fods.2025003">10.3934/fods.2025003</a>
  apa: Cultrera di Montesano, S., Draganov, O., Edelsbrunner, H., &#38; Saghafian,
    M. (2025). Chromatic alpha complexes. <i>Foundations of Data Science</i>. American
    Institute of Mathematical Sciences. <a href="https://doi.org/10.3934/fods.2025003">https://doi.org/10.3934/fods.2025003</a>
  chicago: Cultrera di Montesano, Sebastiano, Ondrej Draganov, Herbert Edelsbrunner,
    and Morteza Saghafian. “Chromatic Alpha Complexes.” <i>Foundations of Data Science</i>.
    American Institute of Mathematical Sciences, 2025. <a href="https://doi.org/10.3934/fods.2025003">https://doi.org/10.3934/fods.2025003</a>.
  ieee: S. Cultrera di Montesano, O. Draganov, H. Edelsbrunner, and M. Saghafian,
    “Chromatic alpha complexes,” <i>Foundations of Data Science</i>, vol. 8. American
    Institute of Mathematical Sciences, pp. 30–62, 2025.
  ista: Cultrera di Montesano S, Draganov O, Edelsbrunner H, Saghafian M. 2025. Chromatic
    alpha complexes. Foundations of Data Science. 8, 30–62.
  mla: Cultrera di Montesano, Sebastiano, et al. “Chromatic Alpha Complexes.” <i>Foundations
    of Data Science</i>, vol. 8, American Institute of Mathematical Sciences, 2025,
    pp. 30–62, doi:<a href="https://doi.org/10.3934/fods.2025003">10.3934/fods.2025003</a>.
  short: S. Cultrera di Montesano, O. Draganov, H. Edelsbrunner, M. Saghafian, Foundations
    of Data Science 8 (2025) 30–62.
corr_author: '1'
date_created: 2025-11-02T23:01:33Z
date_published: 2025-03-01T00:00:00Z
date_updated: 2025-11-04T12:25:47Z
day: '01'
department:
- _id: HeEd
doi: 10.3934/fods.2025003
ec_funded: 1
external_id:
  arxiv:
  - '2212.03128'
intvolume: '         8'
language:
- iso: eng
month: '03'
oa_version: Preprint
page: 30-62
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication: Foundations of Data Science
publication_identifier:
  eissn:
  - 2639-8001
publication_status: epub_ahead
publisher: American Institute of Mathematical Sciences
quality_controlled: '1'
related_material:
  record:
  - id: '15091'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Chromatic alpha complexes
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 8
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '20657'
abstract:
- lang: eng
  text: 'The Upper Bound Theorem for convex polytopes implies that the p-th Betti
    number of the Čech complex of any set of N points in ℝ^d and any radius satisfies
    β_p = O(N^m), with m = min{p+1, ⌈d/2⌉}. We construct sets in even and odd dimensions,
    which prove that this upper bound is asymptotically tight. For example, we describe
    a set of N = 2(n+1) points in ℝ³ and two radii such that the first Betti number
    of the Čech complex at one radius is (n+1)² - 1, and the second Betti number of
    the Čech complex at the other radius is n². '
acknowledgement: The first author is supported by the European Research Council (ERC),
  grant no. 788183, and by the DFG Collaborative Research Center TRR 109, Austrian
  Science Fund (FWF), grant no. I 02979-N35. The second author is supported by the
  European Research Council (ERC), grant “GeoScape” and by the Hungarian Science Foundation
  (NKFIH), grant K-131529. Both authors are supported by the Wittgenstein Prize, Austrian
  Science Fund (FWF), grant no. Z 342-N31.
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: János
  full_name: Pach, János
  id: E62E3130-B088-11EA-B919-BF823C25FEA4
  last_name: Pach
citation:
  ama: Edelsbrunner H, Pach J. Maximum Betti numbers of Čech complexes. <i>Discrete
    &#38; Computational Geometry</i>. 2025. doi:<a href="https://doi.org/10.1007/s00454-025-00796-5">10.1007/s00454-025-00796-5</a>
  apa: Edelsbrunner, H., &#38; Pach, J. (2025). Maximum Betti numbers of Čech complexes.
    <i>Discrete &#38; Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-025-00796-5">https://doi.org/10.1007/s00454-025-00796-5</a>
  chicago: Edelsbrunner, Herbert, and János Pach. “Maximum Betti Numbers of Čech Complexes.”
    <i>Discrete &#38; Computational Geometry</i>. Springer Nature, 2025. <a href="https://doi.org/10.1007/s00454-025-00796-5">https://doi.org/10.1007/s00454-025-00796-5</a>.
  ieee: H. Edelsbrunner and J. Pach, “Maximum Betti numbers of Čech complexes,” <i>Discrete
    &#38; Computational Geometry</i>. Springer Nature, 2025.
  ista: Edelsbrunner H, Pach J. 2025. Maximum Betti numbers of Čech complexes. Discrete
    &#38; Computational Geometry.
  mla: Edelsbrunner, Herbert, and János Pach. “Maximum Betti Numbers of Čech Complexes.”
    <i>Discrete &#38; Computational Geometry</i>, Springer Nature, 2025, doi:<a href="https://doi.org/10.1007/s00454-025-00796-5">10.1007/s00454-025-00796-5</a>.
  short: H. Edelsbrunner, J. Pach, Discrete &#38; Computational Geometry (2025).
corr_author: '1'
date_created: 2025-11-19T09:44:58Z
date_published: 2025-11-10T00:00:00Z
date_updated: 2025-12-01T15:19:21Z
day: '10'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-025-00796-5
ec_funded: 1
external_id:
  arxiv:
  - '2310.14801'
  isi:
  - '001610592600001'
has_accepted_license: '1'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1007/s00454-025-00796-5
month: '11'
oa: 1
oa_version: Published Version
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
- _id: 268116B8-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z00342
  name: Mathematics, Computer Science
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: epub_ahead
publisher: Springer Nature
quality_controlled: '1'
related_material:
  record:
  - id: '17146'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Maximum Betti numbers of Čech complexes
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2025'
...
