---
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: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '19860'
abstract:
- lang: eng
  text: "An eight-partition of a finite set of points (respectively, of a continuous
    mass distribution) in R^3\r\n consists of three planes that divide the space into
    8 octants, such that each open octant contains at most 1/8 of the points (respectively,
    of the mass). In 1966, Hadwiger showed that any mass distribution in R^3 admits
    an eight-partition; moreover, one can prescribe the normal direction of one of
    the three planes. The analogous result for finite point sets follows by a standard
    limit argument. We prove the following variant of this result: any mass distribution
    (or point set) in R^3 admits an eight-partition for which the intersection of
    two of the planes is a line with a prescribed direction. Moreover, we present
    an efficient algorithm for calculating an eight-partition of a set of n points
    in R^3 (with prescribed normal direction of one of the planes) in time O(n^7/3).
    A preliminary version of this work appeared in SoCG’24 (Aronov et al., 40th International
    Symposium on Computational Geometry, 2024)."
acknowledgement: Work by BA was supported by NSF grants CCF 15-40656 and CCF 20-08551,
  and by grant 2014/170 from the US-Israel Binational Science Foundation. Part of
  this research was conducted while BA was visiting ISTA in the summers of 2022 and
  2023. The visit of BA to ISTA in the summer of 2022 was supported by an ISTA Visiting
  Professorship. Research of BA also partially supported by ERC grant no. 882971,
  “GeoScape,” and by the Erdős Center. Work by AB was supported by Australian Research
  Council grant DP220102212. Work by IR was supported by a Tandon School of Engineering
  Fellowship and by NSF Grant CCF-20-08551. BA and AB would like to thank William
  Steiger for insightful initial discussions of the problems addressed in this work.
  Open Access funding enabled and organized by CAUL and its Member Institutions.
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Boris
  full_name: Aronov, Boris
  last_name: Aronov
- first_name: Abdul
  full_name: Basit, Abdul
  last_name: Basit
- first_name: Indu
  full_name: Ramesh, Indu
  last_name: Ramesh
- first_name: Gianluca
  full_name: Tasinato, Gianluca
  id: 0433290C-AF8F-11E9-A4C7-F729E6697425
  last_name: Tasinato
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
citation:
  ama: Aronov B, Basit A, Ramesh I, Tasinato G, Wagner U. Eight-partitioning points
    in 3D, and efficiently too. <i>Discrete &#38; Computational Geometry</i>. 2026;75:1331-1355.
    doi:<a href="https://doi.org/10.1007/s00454-025-00739-0">10.1007/s00454-025-00739-0</a>
  apa: Aronov, B., Basit, A., Ramesh, I., Tasinato, G., &#38; Wagner, U. (2026). Eight-partitioning
    points in 3D, and efficiently too. <i>Discrete &#38; Computational Geometry</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s00454-025-00739-0">https://doi.org/10.1007/s00454-025-00739-0</a>
  chicago: Aronov, Boris, Abdul Basit, Indu Ramesh, Gianluca Tasinato, and Uli Wagner.
    “Eight-Partitioning Points in 3D, and Efficiently Too.” <i>Discrete &#38; Computational
    Geometry</i>. Springer Nature, 2026. <a href="https://doi.org/10.1007/s00454-025-00739-0">https://doi.org/10.1007/s00454-025-00739-0</a>.
  ieee: B. Aronov, A. Basit, I. Ramesh, G. Tasinato, and U. Wagner, “Eight-partitioning
    points in 3D, and efficiently too,” <i>Discrete &#38; Computational Geometry</i>,
    vol. 75. Springer Nature, pp. 1331–1355, 2026.
  ista: Aronov B, Basit A, Ramesh I, Tasinato G, Wagner U. 2026. Eight-partitioning
    points in 3D, and efficiently too. Discrete &#38; Computational Geometry. 75,
    1331–1355.
  mla: Aronov, Boris, et al. “Eight-Partitioning Points in 3D, and Efficiently Too.”
    <i>Discrete &#38; Computational Geometry</i>, vol. 75, Springer Nature, 2026,
    pp. 1331–55, doi:<a href="https://doi.org/10.1007/s00454-025-00739-0">10.1007/s00454-025-00739-0</a>.
  short: B. Aronov, A. Basit, I. Ramesh, G. Tasinato, U. Wagner, Discrete &#38; Computational
    Geometry 75 (2026) 1331–1355.
das_tickbox: '0'
date_created: 2025-06-22T22:02:07Z
date_published: 2026-06-01T00:00:00Z
date_updated: 2026-07-23T11:14:46Z
day: '01'
ddc:
- '500'
department:
- _id: UlWa
doi: 10.1007/s00454-025-00739-0
external_id:
  arxiv:
  - '2403.02627'
  isi:
  - '001506904300001'
file:
- access_level: open_access
  checksum: a32774a0d14f46cafbd77bfb9d9ac4b6
  content_type: application/pdf
  creator: dernst
  date_created: 2026-07-23T11:14:05Z
  date_updated: 2026-07-23T11:14:05Z
  file_id: '22395'
  file_name: 2026_DiscreteCompGeom_Aronov.pdf
  file_size: 525281
  relation: main_file
  success: 1
file_date_updated: 2026-07-23T11:14:05Z
has_accepted_license: '1'
intvolume: '        75'
isi: 1
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: 1331-1355
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  link:
  - relation: erratum
    url: https://doi.org/10.1007/s00454-025-00759-w
  record:
  - id: '18917'
    relation: earlier_version
    status: public
  - id: '20339'
    relation: dissertation_contains
    status: public
researchdata_availability: no
scopus_import: '1'
status: public
supplementarymaterial: yes
title: Eight-partitioning points in 3D, and efficiently too
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: publisher
OA_type: hybrid
_id: '17149'
abstract:
- lang: eng
  text: The approximation of a circle with the edges of a fine square grid distorts
    the perimeter by a factor about 4/Pi. We prove that this factor is the same on
    average (in the ergodic sense) for approximations of any rectifiable curve by
    the edges of any non-exotic Delaunay mosaic (known as Voronoi path), and extend
    the results to all dimensions, generalizing Voronoi paths to Voronoi scapes.
acknowledgement: "The authors thank Ranita Biswas and Tatiana Ezubova for the collaboration
  on computational experiments that motivated the work reported in this paper. The
  authors also thank Daniel Bonnema for proofreading and noticing an issue with the
  original proof of Lemma 4.3.\r\nOpen access funding provided by Institute of Science
  and Technology (IST Austria).\r\nThis 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: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Anton
  full_name: Nikitenko, Anton
  id: 3E4FF1BA-F248-11E8-B48F-1D18A9856A87
  last_name: Nikitenko
  orcid: 0000-0002-0659-3201
citation:
  ama: Edelsbrunner H, Nikitenko A. Average and expected distortion of Voronoi paths
    and scapes. <i>Discrete &#38; Computational Geometry</i>. 2025;73:490-499. doi:<a
    href="https://doi.org/10.1007/s00454-024-00660-y">10.1007/s00454-024-00660-y</a>
  apa: Edelsbrunner, H., &#38; Nikitenko, A. (2025). Average and expected distortion
    of Voronoi paths and scapes. <i>Discrete &#38; Computational Geometry</i>. Springer
    Nature. <a href="https://doi.org/10.1007/s00454-024-00660-y">https://doi.org/10.1007/s00454-024-00660-y</a>
  chicago: Edelsbrunner, Herbert, and Anton Nikitenko. “Average and Expected Distortion
    of Voronoi Paths and Scapes.” <i>Discrete &#38; Computational Geometry</i>. Springer
    Nature, 2025. <a href="https://doi.org/10.1007/s00454-024-00660-y">https://doi.org/10.1007/s00454-024-00660-y</a>.
  ieee: H. Edelsbrunner and A. Nikitenko, “Average and expected distortion of Voronoi
    paths and scapes,” <i>Discrete &#38; Computational Geometry</i>, vol. 73. Springer
    Nature, pp. 490–499, 2025.
  ista: Edelsbrunner H, Nikitenko A. 2025. Average and expected distortion of Voronoi
    paths and scapes. Discrete &#38; Computational Geometry. 73, 490–499.
  mla: Edelsbrunner, Herbert, and Anton Nikitenko. “Average and Expected Distortion
    of Voronoi Paths and Scapes.” <i>Discrete &#38; Computational Geometry</i>, vol.
    73, Springer Nature, 2025, pp. 490–99, doi:<a href="https://doi.org/10.1007/s00454-024-00660-y">10.1007/s00454-024-00660-y</a>.
  short: H. Edelsbrunner, A. Nikitenko, Discrete &#38; Computational Geometry 73 (2025)
    490–499.
corr_author: '1'
date_created: 2024-06-16T22:01:07Z
date_published: 2025-03-01T00:00:00Z
date_updated: 2026-02-16T12:18:50Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-024-00660-y
ec_funded: 1
external_id:
  arxiv:
  - '2012.03350'
  isi:
  - '001238566200004'
  pmid:
  - '39974750'
file:
- access_level: open_access
  checksum: ffb0c818222138f9f113f4bbea41e834
  content_type: application/pdf
  creator: dernst
  date_created: 2025-04-23T07:31:32Z
  date_updated: 2025-04-23T07:31:32Z
  file_id: '19610'
  file_name: 2025_DiscreteComputGeom_EdelsbrunnerHe.pdf
  file_size: 283443
  relation: main_file
  success: 1
file_date_updated: 2025-04-23T07:31:32Z
has_accepted_license: '1'
intvolume: '        73'
isi: 1
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
page: 490-499
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: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Average and expected distortion of Voronoi paths and scapes
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: 73
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'
...
---
OA_place: repository
OA_type: green
_id: '13974'
abstract:
- lang: eng
  text: The Tverberg theorem is one of the cornerstones of discrete geometry. It states
    that, given a set X of at least (d+1)(r−1)+1 points in Rd, one can find a partition
    X=X1∪⋯∪Xr of X, such that the convex hulls of the Xi, i=1,…,r, all share a common
    point. In this paper, we prove a trengthening of this theorem that guarantees
    a partition which, in addition to the above, has the property that the boundaries
    of full-dimensional convex hulls have pairwise nonempty intersections. Possible
    generalizations and algorithmic aspects are also discussed. As a concrete application,
    we show that any n points in the plane in general position span ⌊n/3⌋ vertex-disjoint
    triangles that are pairwise crossing, meaning that their boundaries have pairwise
    nonempty intersections; this number is clearly best possible. A previous result
    of Álvarez-Rebollar et al. guarantees ⌊n/6⌋pairwise crossing triangles. Our result
    generalizes to a result about simplices in Rd, d≥2.
acknowledgement: "Part of the research leading to this paper was done during the 16th
  Gremo Workshop on Open Problems (GWOP), Waltensburg, Switzerland, June 12–16, 2018.
  We thank Patrick Schnider for suggesting the problem, and Stefan Felsner, Malte
  Milatz, and Emo Welzl for fruitful discussions during the workshop. We also thank
  Stefan Felsner and Manfred Scheucher for finding, communicating the example from
  Sect. 3.3, and the kind permission to include their visualization of the point set.
  We thank Dömötör Pálvölgyi, the SoCG reviewers, and DCG reviewers for various helpful
  comments.\r\nR. Fulek gratefully acknowledges support from Austrian Science Fund
  (FWF), Project  M2281-N35. A. Kupavskii was supported by the Advanced Postdoc.Mobility
  Grant no. P300P2_177839 of the Swiss National Science Foundation. Research by P.
  Valtr was supported by the Grant no. 18-19158 S of the Czech Science Foundation
  (GAČR)."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Radoslav
  full_name: Fulek, Radoslav
  id: 39F3FFE4-F248-11E8-B48F-1D18A9856A87
  last_name: Fulek
  orcid: 0000-0001-8485-1774
- first_name: Bernd
  full_name: Gärtner, Bernd
  last_name: Gärtner
- first_name: Andrey
  full_name: Kupavskii, Andrey
  last_name: Kupavskii
- first_name: Pavel
  full_name: Valtr, Pavel
  last_name: Valtr
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
citation:
  ama: Fulek R, Gärtner B, Kupavskii A, Valtr P, Wagner U. The crossing Tverberg theorem.
    <i>Discrete and Computational Geometry</i>. 2024;72:831-848. doi:<a href="https://doi.org/10.1007/s00454-023-00532-x">10.1007/s00454-023-00532-x</a>
  apa: Fulek, R., Gärtner, B., Kupavskii, A., Valtr, P., &#38; Wagner, U. (2024).
    The crossing Tverberg theorem. <i>Discrete and Computational Geometry</i>. Springer
    Nature. <a href="https://doi.org/10.1007/s00454-023-00532-x">https://doi.org/10.1007/s00454-023-00532-x</a>
  chicago: Fulek, Radoslav, Bernd Gärtner, Andrey Kupavskii, Pavel Valtr, and Uli
    Wagner. “The Crossing Tverberg Theorem.” <i>Discrete and Computational Geometry</i>.
    Springer Nature, 2024. <a href="https://doi.org/10.1007/s00454-023-00532-x">https://doi.org/10.1007/s00454-023-00532-x</a>.
  ieee: R. Fulek, B. Gärtner, A. Kupavskii, P. Valtr, and U. Wagner, “The crossing
    Tverberg theorem,” <i>Discrete and Computational Geometry</i>, vol. 72. Springer
    Nature, pp. 831–848, 2024.
  ista: Fulek R, Gärtner B, Kupavskii A, Valtr P, Wagner U. 2024. The crossing Tverberg
    theorem. Discrete and Computational Geometry. 72, 831–848.
  mla: Fulek, Radoslav, et al. “The Crossing Tverberg Theorem.” <i>Discrete and Computational
    Geometry</i>, vol. 72, Springer Nature, 2024, pp. 831–48, doi:<a href="https://doi.org/10.1007/s00454-023-00532-x">10.1007/s00454-023-00532-x</a>.
  short: R. Fulek, B. Gärtner, A. Kupavskii, P. Valtr, U. Wagner, Discrete and Computational
    Geometry 72 (2024) 831–848.
date_created: 2023-08-06T22:01:12Z
date_published: 2024-09-01T00:00:00Z
date_updated: 2025-04-14T13:52:36Z
day: '01'
department:
- _id: UlWa
doi: 10.1007/s00454-023-00532-x
external_id:
  arxiv:
  - '1812.04911'
  isi:
  - '001038546500001'
intvolume: '        72'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.1812.04911
month: '09'
oa: 1
oa_version: Preprint
page: 831-848
project:
- _id: 261FA626-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: M02281
  name: Eliminating intersections in drawings of graphs
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: '6647'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: The crossing Tverberg theorem
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 72
year: '2024'
...
---
_id: '14345'
abstract:
- lang: eng
  text: For a locally finite set in R2, the order-k Brillouin tessellations form an
    infinite sequence of convex face-to-face tilings of the plane. If the set is coarsely
    dense and generic, then the corresponding infinite sequences of minimum and maximum
    angles are both monotonic in k. As an example, a stationary Poisson point process
    in R2  is locally finite, coarsely dense, and generic with probability one. For
    such a set, the distributions of angles in the Voronoi tessellations, Delaunay
    mosaics, and Brillouin tessellations are independent of the order and can be derived
    from the formula for angles in order-1 Delaunay mosaics given by Miles (Math.
    Biosci. 6, 85–127 (1970)).
acknowledgement: Work by all authors but A. Garber 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 A. Garber is partially
  supported by the Alexander von Humboldt Foundation.
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: 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. On angles in higher
    order Brillouin tessellations and related tilings in the plane. <i>Discrete and
    Computational Geometry</i>. 2024;72:29-48. doi:<a href="https://doi.org/10.1007/s00454-023-00566-1">10.1007/s00454-023-00566-1</a>
  apa: Edelsbrunner, H., Garber, A., Ghafari, M., Heiss, T., &#38; Saghafian, M. (2024).
    On angles in higher order Brillouin tessellations and related tilings in the plane.
    <i>Discrete and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-023-00566-1">https://doi.org/10.1007/s00454-023-00566-1</a>
  chicago: Edelsbrunner, Herbert, Alexey Garber, Mohadese Ghafari, Teresa Heiss, and
    Morteza Saghafian. “On Angles in Higher Order Brillouin Tessellations and Related
    Tilings in the Plane.” <i>Discrete and Computational Geometry</i>. Springer Nature,
    2024. <a href="https://doi.org/10.1007/s00454-023-00566-1">https://doi.org/10.1007/s00454-023-00566-1</a>.
  ieee: H. Edelsbrunner, A. Garber, M. Ghafari, T. Heiss, and M. Saghafian, “On angles
    in higher order Brillouin tessellations and related tilings in the plane,” <i>Discrete
    and Computational Geometry</i>, vol. 72. Springer Nature, pp. 29–48, 2024.
  ista: Edelsbrunner H, Garber A, Ghafari M, Heiss T, Saghafian M. 2024. On angles
    in higher order Brillouin tessellations and related tilings in the plane. Discrete
    and Computational Geometry. 72, 29–48.
  mla: Edelsbrunner, Herbert, et al. “On Angles in Higher Order Brillouin Tessellations
    and Related Tilings in the Plane.” <i>Discrete and Computational Geometry</i>,
    vol. 72, Springer Nature, 2024, pp. 29–48, doi:<a href="https://doi.org/10.1007/s00454-023-00566-1">10.1007/s00454-023-00566-1</a>.
  short: H. Edelsbrunner, A. Garber, M. Ghafari, T. Heiss, M. Saghafian, Discrete
    and Computational Geometry 72 (2024) 29–48.
corr_author: '1'
date_created: 2023-09-17T22:01:10Z
date_published: 2024-07-01T00:00:00Z
date_updated: 2025-04-23T08:41:59Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-023-00566-1
ec_funded: 1
external_id:
  arxiv:
  - '2204.01076'
  isi:
  - '001060727600004'
  pmid:
  - '39610762'
file:
- access_level: open_access
  checksum: b207b4e00f904e8ea8a30e24f0251f79
  content_type: application/pdf
  creator: dernst
  date_created: 2024-07-22T09:43:19Z
  date_updated: 2024-07-22T09:43:19Z
  file_id: '17301'
  file_name: 2024_DiscreteComputGeom_Edelsbrunner.pdf
  file_size: 892019
  relation: main_file
  success: 1
file_date_updated: 2024-07-22T09:43:19Z
has_accepted_license: '1'
intvolume: '        72'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: 29-48
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: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: On angles in higher order Brillouin tessellations and related tilings in the
  plane
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: 72
year: '2024'
...
---
_id: '11999'
abstract:
- lang: eng
  text: 'A simple drawing D(G) of a graph G is one where each pair of edges share
    at most one point: either a common endpoint or a proper crossing. An edge e in
    the complement of G can be inserted into D(G) if there exists a simple drawing
    of G+e extending D(G). As a result of Levi’s Enlargement Lemma, if a drawing is
    rectilinear (pseudolinear), that is, the edges can be extended into an arrangement
    of lines (pseudolines), then any edge in the complement of G can be inserted.
    In contrast, we show that it is NP-complete to decide whether one edge can be
    inserted into a simple drawing. This remains true even if we assume that the drawing
    is pseudocircular, that is, the edges can be extended to an arrangement of pseudocircles.
    On the positive side, we show that, given an arrangement of pseudocircles A and
    a pseudosegment σ, it can be decided in polynomial time whether there exists a
    pseudocircle Φσ extending σ for which A∪{Φσ} is again an arrangement of pseudocircles.'
acknowledgement: 'This work was started during the 6th Austrian–Japanese–Mexican–Spanish
  Workshop on Discrete Geometry in June 2019 in Austria. We thank all the participants
  for the good atmosphere as well as discussions on the topic. Also, we thank Jan
  Kynčl for sending us remarks on a preliminary version of this work and an anonymous
  referee for further helpful comments.Alan Arroyo was funded by the Marie Skłodowska-Curie
  grant agreement No 754411. Fabian Klute was partially supported by the Netherlands
  Organisation for Scientific Research (NWO) under project no. 612.001.651 and by
  the Austrian Science Fund (FWF): J-4510. Irene Parada and Birgit Vogtenhuber were
  partially supported by the Austrian Science Fund (FWF): W1230 and within the collaborative
  DACH project Arrangements and Drawings as FWF project I 3340-N35. Irene Parada was
  also partially supported by the Independent Research Fund Denmark grant 2020-2023
  (9131-00044B) Dynamic Network Analysis and by the Margarita Salas Fellowship funded
  by the Ministry of Universities of Spain and the European Union (NextGenerationEU).
  Tilo Wiedera was supported by the German Research Foundation (DFG) grant CH 897/2-2.'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: Alan M
  full_name: Arroyo Guevara, Alan M
  id: 3207FDC6-F248-11E8-B48F-1D18A9856A87
  last_name: Arroyo Guevara
  orcid: 0000-0003-2401-8670
- first_name: Fabian
  full_name: Klute, Fabian
  last_name: Klute
- first_name: Irene
  full_name: Parada, Irene
  last_name: Parada
- first_name: Birgit
  full_name: Vogtenhuber, Birgit
  last_name: Vogtenhuber
- first_name: Raimund
  full_name: Seidel, Raimund
  last_name: Seidel
- first_name: Tilo
  full_name: Wiedera, Tilo
  last_name: Wiedera
citation:
  ama: Arroyo Guevara AM, Klute F, Parada I, Vogtenhuber B, Seidel R, Wiedera T. Inserting
    one edge into a simple drawing is hard. <i>Discrete and Computational Geometry</i>.
    2023;69:745–770. doi:<a href="https://doi.org/10.1007/s00454-022-00394-9">10.1007/s00454-022-00394-9</a>
  apa: Arroyo Guevara, A. M., Klute, F., Parada, I., Vogtenhuber, B., Seidel, R.,
    &#38; Wiedera, T. (2023). Inserting one edge into a simple drawing is hard. <i>Discrete
    and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-022-00394-9">https://doi.org/10.1007/s00454-022-00394-9</a>
  chicago: Arroyo Guevara, Alan M, Fabian Klute, Irene Parada, Birgit Vogtenhuber,
    Raimund Seidel, and Tilo Wiedera. “Inserting One Edge into a Simple Drawing Is
    Hard.” <i>Discrete and Computational Geometry</i>. Springer Nature, 2023. <a href="https://doi.org/10.1007/s00454-022-00394-9">https://doi.org/10.1007/s00454-022-00394-9</a>.
  ieee: A. M. Arroyo Guevara, F. Klute, I. Parada, B. Vogtenhuber, R. Seidel, and
    T. Wiedera, “Inserting one edge into a simple drawing is hard,” <i>Discrete and
    Computational Geometry</i>, vol. 69. Springer Nature, pp. 745–770, 2023.
  ista: Arroyo Guevara AM, Klute F, Parada I, Vogtenhuber B, Seidel R, Wiedera T.
    2023. Inserting one edge into a simple drawing is hard. Discrete and Computational
    Geometry. 69, 745–770.
  mla: Arroyo Guevara, Alan M., et al. “Inserting One Edge into a Simple Drawing Is
    Hard.” <i>Discrete and Computational Geometry</i>, vol. 69, Springer Nature, 2023,
    pp. 745–770, doi:<a href="https://doi.org/10.1007/s00454-022-00394-9">10.1007/s00454-022-00394-9</a>.
  short: A.M. Arroyo Guevara, F. Klute, I. Parada, B. Vogtenhuber, R. Seidel, T. Wiedera,
    Discrete and Computational Geometry 69 (2023) 745–770.
date_created: 2022-08-28T22:02:01Z
date_published: 2023-04-01T00:00:00Z
date_updated: 2025-04-14T07:43:59Z
day: '01'
ddc:
- '510'
department:
- _id: UlWa
doi: 10.1007/s00454-022-00394-9
ec_funded: 1
external_id:
  arxiv:
  - '1909.07347'
  isi:
  - '000840292800001'
file:
- access_level: open_access
  checksum: def7ae3b28d9fd6aec16450e40090302
  content_type: application/pdf
  creator: alisjak
  date_created: 2022-08-29T11:23:15Z
  date_updated: 2022-08-29T11:23:15Z
  file_id: '12006'
  file_name: 2022_DiscreteandComputionalGeometry_Arroyo.pdf
  file_size: 1002218
  relation: main_file
  success: 1
file_date_updated: 2022-08-29T11:23:15Z
has_accepted_license: '1'
intvolume: '        69'
isi: 1
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
page: 745–770
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Inserting one edge into a simple drawing is hard
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: 69
year: '2023'
...
---
_id: '12287'
abstract:
- lang: eng
  text: We present criteria for establishing a triangulation of a manifold. Given
    a manifold M, a simplicial complex A, and a map H from the underlying space of
    A to M, our criteria are presented in local coordinate charts for M, and ensure
    that H is a homeomorphism. These criteria do not require a differentiable structure,
    or even an explicit metric on M. No Delaunay property of A is assumed. The result
    provides a triangulation guarantee for algorithms that construct a simplicial
    complex by working in local coordinate patches. Because the criteria are easily
    verified in such a setting, they are expected to be of general use.
acknowledgement: "This work has been funded by the European Research Council under
  the European Union’s ERC Grant Agreement number 339025 GUDHI (Algorithmic Foundations
  of Geometric Understanding in Higher Dimensions). Arijit Ghosh is supported by Ramanujan
  Fellowship (No. SB/S2/RJN-064/2015). Part of this work was done when Arijit Ghosh
  was a Researcher at Max-Planck-Institute for Informatics, Germany, supported by
  the IndoGerman Max Planck Center for Computer Science (IMPECS). Mathijs Wintraecken
  also received funding from the European Union’s Horizon 2020 research and innovation
  programme under the Marie Skłodowska-Curie grant agreement No. 754411 and the Austrian
  Science Fund (FWF): M-3073. A part of the results described in this paper were presented
  at SoCG 2018 and in [3]. \r\nOpen access funding provided by the Austrian Science
  Fund (FWF)."
article_processing_charge: No
article_type: original
author:
- first_name: Jean-Daniel
  full_name: Boissonnat, Jean-Daniel
  last_name: Boissonnat
- first_name: Ramsay
  full_name: Dyer, Ramsay
  last_name: Dyer
- first_name: Arijit
  full_name: Ghosh, Arijit
  last_name: Ghosh
- first_name: Mathijs
  full_name: Wintraecken, Mathijs
  id: 307CFBC8-F248-11E8-B48F-1D18A9856A87
  last_name: Wintraecken
  orcid: 0000-0002-7472-2220
citation:
  ama: Boissonnat J-D, Dyer R, Ghosh A, Wintraecken M. Local criteria for triangulating
    general manifolds. <i>Discrete &#38; Computational Geometry</i>. 2023;69:156-191.
    doi:<a href="https://doi.org/10.1007/s00454-022-00431-7">10.1007/s00454-022-00431-7</a>
  apa: Boissonnat, J.-D., Dyer, R., Ghosh, A., &#38; Wintraecken, M. (2023). Local
    criteria for triangulating general manifolds. <i>Discrete &#38; Computational
    Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-022-00431-7">https://doi.org/10.1007/s00454-022-00431-7</a>
  chicago: Boissonnat, Jean-Daniel, Ramsay Dyer, Arijit Ghosh, and Mathijs Wintraecken.
    “Local Criteria for Triangulating General Manifolds.” <i>Discrete &#38; Computational
    Geometry</i>. Springer Nature, 2023. <a href="https://doi.org/10.1007/s00454-022-00431-7">https://doi.org/10.1007/s00454-022-00431-7</a>.
  ieee: J.-D. Boissonnat, R. Dyer, A. Ghosh, and M. Wintraecken, “Local criteria for
    triangulating general manifolds,” <i>Discrete &#38; Computational Geometry</i>,
    vol. 69. Springer Nature, pp. 156–191, 2023.
  ista: Boissonnat J-D, Dyer R, Ghosh A, Wintraecken M. 2023. Local criteria for triangulating
    general manifolds. Discrete &#38; Computational Geometry. 69, 156–191.
  mla: Boissonnat, Jean-Daniel, et al. “Local Criteria for Triangulating General Manifolds.”
    <i>Discrete &#38; Computational Geometry</i>, vol. 69, Springer Nature, 2023,
    pp. 156–91, doi:<a href="https://doi.org/10.1007/s00454-022-00431-7">10.1007/s00454-022-00431-7</a>.
  short: J.-D. Boissonnat, R. Dyer, A. Ghosh, M. Wintraecken, Discrete &#38; Computational
    Geometry 69 (2023) 156–191.
corr_author: '1'
date_created: 2023-01-16T10:04:06Z
date_published: 2023-01-01T00:00:00Z
date_updated: 2025-04-14T07:44:00Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-022-00431-7
ec_funded: 1
external_id:
  isi:
  - '000862193600001'
file:
- access_level: open_access
  checksum: 46352e0ee71e460848f88685ca852681
  content_type: application/pdf
  creator: dernst
  date_created: 2023-02-02T11:01:10Z
  date_updated: 2023-02-02T11:01:10Z
  file_id: '12488'
  file_name: 2023_DiscreteCompGeometry_Boissonnat.pdf
  file_size: 582850
  relation: main_file
  success: 1
file_date_updated: 2023-02-02T11:01:10Z
has_accepted_license: '1'
intvolume: '        69'
isi: 1
keyword:
- Computational Theory and Mathematics
- Discrete Mathematics and Combinatorics
- Geometry and Topology
- Theoretical Computer Science
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: 156-191
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
- _id: fc390959-9c52-11eb-aca3-afa58bd282b2
  grant_number: M03073
  name: Learning and triangulating manifolds via collapses
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Local criteria for triangulating general manifolds
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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 69
year: '2023'
...
---
_id: '12709'
abstract:
- lang: eng
  text: Given a finite set A ⊂ ℝ^d, let Cov_{r,k} denote the set of all points within
    distance r to at least k points of A. Allowing r and k to vary, we obtain a 2-parameter
    family of spaces that grow larger when r increases or k decreases, called the
    multicover bifiltration. Motivated by the problem of computing the homology of
    this bifiltration, we introduce two closely related combinatorial bifiltrations,
    one polyhedral and the other simplicial, which are both topologically equivalent
    to the multicover bifiltration and far smaller than a Čech-based model considered
    in prior work of Sheehy. Our polyhedral construction is a bifiltration of the
    rhomboid tiling of Edelsbrunner and Osang, and can be efficiently computed using
    a variant of an algorithm given by these authors as well. Using an implementation
    for dimension 2 and 3, we provide experimental results. Our simplicial construction
    is useful for understanding the polyhedral construction and proving its correctness.
acknowledgement: We thank the anonymous reviewers for many helpful comments and suggestions,
  which led to substantial improvements of the paper. The first two authors were supported
  by the Austrian Science Fund (FWF) grant number P 29984-N35 and W1230. The first
  author was partly supported by an Austrian Marshall Plan Scholarship, and by the
  Brummer & Partners MathDataLab. A conference version of this paper was presented
  at the 37th International Symposium on Computational Geometry (SoCG 2021). Open
  access funding provided by the Royal Institute of Technology.
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: René
  full_name: Corbet, René
  last_name: Corbet
- first_name: Michael
  full_name: Kerber, Michael
  id: 36E4574A-F248-11E8-B48F-1D18A9856A87
  last_name: Kerber
  orcid: 0000-0002-8030-9299
- first_name: Michael
  full_name: Lesnick, Michael
  last_name: Lesnick
- first_name: Georg F
  full_name: Osang, Georg F
  id: 464B40D6-F248-11E8-B48F-1D18A9856A87
  last_name: Osang
  orcid: 0000-0002-8882-5116
citation:
  ama: Corbet R, Kerber M, Lesnick M, Osang GF. Computing the multicover bifiltration.
    <i>Discrete and Computational Geometry</i>. 2023;70:376-405. doi:<a href="https://doi.org/10.1007/s00454-022-00476-8">10.1007/s00454-022-00476-8</a>
  apa: Corbet, R., Kerber, M., Lesnick, M., &#38; Osang, G. F. (2023). Computing the
    multicover bifiltration. <i>Discrete and Computational Geometry</i>. Springer
    Nature. <a href="https://doi.org/10.1007/s00454-022-00476-8">https://doi.org/10.1007/s00454-022-00476-8</a>
  chicago: Corbet, René, Michael Kerber, Michael Lesnick, and Georg F Osang. “Computing
    the Multicover Bifiltration.” <i>Discrete and Computational Geometry</i>. Springer
    Nature, 2023. <a href="https://doi.org/10.1007/s00454-022-00476-8">https://doi.org/10.1007/s00454-022-00476-8</a>.
  ieee: R. Corbet, M. Kerber, M. Lesnick, and G. F. Osang, “Computing the multicover
    bifiltration,” <i>Discrete and Computational Geometry</i>, vol. 70. Springer Nature,
    pp. 376–405, 2023.
  ista: Corbet R, Kerber M, Lesnick M, Osang GF. 2023. Computing the multicover bifiltration.
    Discrete and Computational Geometry. 70, 376–405.
  mla: Corbet, René, et al. “Computing the Multicover Bifiltration.” <i>Discrete and
    Computational Geometry</i>, vol. 70, Springer Nature, 2023, pp. 376–405, doi:<a
    href="https://doi.org/10.1007/s00454-022-00476-8">10.1007/s00454-022-00476-8</a>.
  short: R. Corbet, M. Kerber, M. Lesnick, G.F. Osang, Discrete and Computational
    Geometry 70 (2023) 376–405.
date_created: 2023-03-05T23:01:06Z
date_published: 2023-09-01T00:00:00Z
date_updated: 2025-07-10T12:01:57Z
day: '01'
ddc:
- '000'
department:
- _id: HeEd
doi: 10.1007/s00454-022-00476-8
external_id:
  arxiv:
  - '2103.07823'
  isi:
  - '000936496800001'
  pmid:
  - '37581017'
file:
- access_level: open_access
  checksum: 71ce7e59f7ee4620acc704fecca620c2
  content_type: application/pdf
  creator: cchlebak
  date_created: 2023-03-07T14:40:14Z
  date_updated: 2023-03-07T14:40:14Z
  file_id: '12715'
  file_name: 2023_DisCompGeo_Corbet.pdf
  file_size: 1359323
  relation: main_file
  success: 1
file_date_updated: 2023-03-07T14:40:14Z
has_accepted_license: '1'
intvolume: '        70'
isi: 1
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: 376-405
pmid: 1
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: '9605'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Computing the multicover bifiltration
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: 70
year: '2023'
...
---
_id: '12764'
abstract:
- lang: eng
  text: We study a new discretization of the Gaussian curvature for polyhedral surfaces.
    This discrete Gaussian curvature is defined on each conical singularity of a polyhedral
    surface as the quotient of the angle defect and the area of the Voronoi cell corresponding
    to the singularity. We divide polyhedral surfaces into discrete conformal classes
    using a generalization of discrete conformal equivalence pioneered by Feng Luo.
    We subsequently show that, in every discrete conformal class, there exists a polyhedral
    surface with constant discrete Gaussian curvature. We also provide explicit examples
    to demonstrate that this surface is in general not unique.
acknowledgement: Open access funding provided by the Austrian Science Fund (FWF).
  This research was supported by the FWF grant, Project number I4245-N35, and by the
  Deutsche Forschungsgemeinschaft (DFG - German Research Foundation) - Project-ID
  195170736 - TRR109.
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Hana
  full_name: Kourimska, Hana
  id: D9B8E14C-3C26-11EA-98F5-1F833DDC885E
  last_name: Kourimska
  orcid: 0000-0001-7841-0091
citation:
  ama: Kourimska H. Discrete yamabe problem for polyhedral surfaces. <i>Discrete and
    Computational Geometry</i>. 2023;70:123-153. doi:<a href="https://doi.org/10.1007/s00454-023-00484-2">10.1007/s00454-023-00484-2</a>
  apa: Kourimska, H. (2023). Discrete yamabe problem for polyhedral surfaces. <i>Discrete
    and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-023-00484-2">https://doi.org/10.1007/s00454-023-00484-2</a>
  chicago: Kourimska, Hana. “Discrete Yamabe Problem for Polyhedral Surfaces.” <i>Discrete
    and Computational Geometry</i>. Springer Nature, 2023. <a href="https://doi.org/10.1007/s00454-023-00484-2">https://doi.org/10.1007/s00454-023-00484-2</a>.
  ieee: H. Kourimska, “Discrete yamabe problem for polyhedral surfaces,” <i>Discrete
    and Computational Geometry</i>, vol. 70. Springer Nature, pp. 123–153, 2023.
  ista: Kourimska H. 2023. Discrete yamabe problem for polyhedral surfaces. Discrete
    and Computational Geometry. 70, 123–153.
  mla: Kourimska, Hana. “Discrete Yamabe Problem for Polyhedral Surfaces.” <i>Discrete
    and Computational Geometry</i>, vol. 70, Springer Nature, 2023, pp. 123–53, doi:<a
    href="https://doi.org/10.1007/s00454-023-00484-2">10.1007/s00454-023-00484-2</a>.
  short: H. Kourimska, Discrete and Computational Geometry 70 (2023) 123–153.
corr_author: '1'
date_created: 2023-03-26T22:01:09Z
date_published: 2023-07-01T00:00:00Z
date_updated: 2025-04-23T08:59:15Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-023-00484-2
external_id:
  isi:
  - '000948148000001'
  pmid:
  - '37292248'
file:
- access_level: open_access
  checksum: cdbf90ba4a7ddcb190d37b9e9d4cb9d3
  content_type: application/pdf
  creator: dernst
  date_created: 2023-10-04T11:46:24Z
  date_updated: 2023-10-04T11:46:24Z
  file_id: '14396'
  file_name: 2023_DiscreteGeometry_Kourimska.pdf
  file_size: 1026683
  relation: main_file
  success: 1
file_date_updated: 2023-10-04T11:46:24Z
has_accepted_license: '1'
intvolume: '        70'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: 123-153
pmid: 1
project:
- _id: 26AD5D90-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I04245
  name: Algebraic Footprints of Geometric Features in Homology
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Discrete yamabe problem for polyhedral surfaces
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: 70
year: '2023'
...
---
_id: '13270'
abstract:
- lang: eng
  text: "Consider a geodesic triangle on a surface of constant curvature and subdivide
    it recursively into four triangles by joining the midpoints of its edges. We show
    the existence of a uniform δ>0\r\n such that, at any step of the subdivision,
    all the triangle angles lie in the interval (δ,π−δ)\r\n. Additionally, we exhibit
    stabilising behaviours for both angles and lengths as this subdivision progresses."
acknowledgement: Open access funding provided by the Institute of Science and Technology
  (IST Austria).
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Florestan R
  full_name: Brunck, Florestan R
  id: 6ab6e556-f394-11eb-9cf6-9dfb78f00d8d
  last_name: Brunck
citation:
  ama: Brunck FR. Iterated medial triangle subdivision in surfaces of constant curvature.
    <i>Discrete and Computational Geometry</i>. 2023;70(3):1059-1089. doi:<a href="https://doi.org/10.1007/s00454-023-00500-5">10.1007/s00454-023-00500-5</a>
  apa: Brunck, F. R. (2023). Iterated medial triangle subdivision in surfaces of constant
    curvature. <i>Discrete and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-023-00500-5">https://doi.org/10.1007/s00454-023-00500-5</a>
  chicago: Brunck, Florestan R. “Iterated Medial Triangle Subdivision in Surfaces
    of Constant Curvature.” <i>Discrete and Computational Geometry</i>. Springer Nature,
    2023. <a href="https://doi.org/10.1007/s00454-023-00500-5">https://doi.org/10.1007/s00454-023-00500-5</a>.
  ieee: F. R. Brunck, “Iterated medial triangle subdivision in surfaces of constant
    curvature,” <i>Discrete and Computational Geometry</i>, vol. 70, no. 3. Springer
    Nature, pp. 1059–1089, 2023.
  ista: Brunck FR. 2023. Iterated medial triangle subdivision in surfaces of constant
    curvature. Discrete and Computational Geometry. 70(3), 1059–1089.
  mla: Brunck, Florestan R. “Iterated Medial Triangle Subdivision in Surfaces of Constant
    Curvature.” <i>Discrete and Computational Geometry</i>, vol. 70, no. 3, Springer
    Nature, 2023, pp. 1059–89, doi:<a href="https://doi.org/10.1007/s00454-023-00500-5">10.1007/s00454-023-00500-5</a>.
  short: F.R. Brunck, Discrete and Computational Geometry 70 (2023) 1059–1089.
corr_author: '1'
date_created: 2023-07-23T22:01:14Z
date_published: 2023-07-05T00:00:00Z
date_updated: 2024-10-09T21:06:01Z
day: '05'
ddc:
- '510'
department:
- _id: UlWa
doi: 10.1007/s00454-023-00500-5
external_id:
  arxiv:
  - '2107.04112'
  isi:
  - '001023742800003'
file:
- access_level: open_access
  checksum: 865e68daafdd4edcfc280172ec50f5ea
  content_type: application/pdf
  creator: dernst
  date_created: 2024-01-29T11:15:22Z
  date_updated: 2024-01-29T11:15:22Z
  file_id: '14897'
  file_name: 2023_DiscreteComputGeometry_Brunck.pdf
  file_size: 1466020
  relation: main_file
  success: 1
file_date_updated: 2024-01-29T11:15:22Z
has_accepted_license: '1'
intvolume: '        70'
isi: 1
issue: '3'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: 1059-1089
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Iterated medial triangle subdivision in surfaces of constant curvature
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: 70
year: '2023'
...
---
_id: '11593'
abstract:
- lang: eng
  text: 'A drawing of a graph on a surface is independently even if every pair of
    nonadjacent edges in the drawing crosses an even number of times. The Z2 -genus
    of a graph G is the minimum g such that G has an independently even drawing on
    the orientable surface of genus g. An unpublished result by Robertson and Seymour
    implies that for every t, every graph of sufficiently large genus contains as
    a minor a projective t×t grid or one of the following so-called t -Kuratowski
    graphs: K3,t, or t copies of K5 or K3,3 sharing at most two common vertices. We
    show that the Z2-genus of graphs in these families is unbounded in t; in fact,
    equal to their genus. Together, this implies that the genus of a graph is bounded
    from above by a function of its Z2-genus, solving a problem posed by Schaefer
    and Štefankovič, and giving an approximate version of the Hanani–Tutte theorem
    on orientable surfaces. We also obtain an analogous result for Euler genus and
    Euler Z2-genus of graphs.'
acknowledgement: "We thank Zdeněk Dvořák, Xavier Goaoc, and Pavel Paták for helpful
  discussions. We also thank Bojan Mohar, Paul Seymour, Gelasio Salazar, Jim Geelen,
  and John Maharry for information about their unpublished results related to Conjecture
  3.1. Finally we thank the reviewers for corrections and suggestions for improving
  the presentation.\r\nSupported by Austrian Science Fund (FWF): M2281-N35. Supported
  by project 19-04113Y of the Czech Science Foundation (GAČR), by the Czech-French
  collaboration project EMBEDS II (CZ: 7AMB17FR029, FR: 38087RM), and by Charles University
  project UNCE/SCI/004."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Radoslav
  full_name: Fulek, Radoslav
  id: 39F3FFE4-F248-11E8-B48F-1D18A9856A87
  last_name: Fulek
  orcid: 0000-0001-8485-1774
- first_name: Jan
  full_name: Kynčl, Jan
  last_name: Kynčl
citation:
  ama: Fulek R, Kynčl J. The Z2-Genus of Kuratowski minors. <i>Discrete and Computational
    Geometry</i>. 2022;68:425-447. doi:<a href="https://doi.org/10.1007/s00454-022-00412-w">10.1007/s00454-022-00412-w</a>
  apa: Fulek, R., &#38; Kynčl, J. (2022). The Z2-Genus of Kuratowski minors. <i>Discrete
    and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-022-00412-w">https://doi.org/10.1007/s00454-022-00412-w</a>
  chicago: Fulek, Radoslav, and Jan Kynčl. “The Z2-Genus of Kuratowski Minors.” <i>Discrete
    and Computational Geometry</i>. Springer Nature, 2022. <a href="https://doi.org/10.1007/s00454-022-00412-w">https://doi.org/10.1007/s00454-022-00412-w</a>.
  ieee: R. Fulek and J. Kynčl, “The Z2-Genus of Kuratowski minors,” <i>Discrete and
    Computational Geometry</i>, vol. 68. Springer Nature, pp. 425–447, 2022.
  ista: Fulek R, Kynčl J. 2022. The Z2-Genus of Kuratowski minors. Discrete and Computational
    Geometry. 68, 425–447.
  mla: Fulek, Radoslav, and Jan Kynčl. “The Z2-Genus of Kuratowski Minors.” <i>Discrete
    and Computational Geometry</i>, vol. 68, Springer Nature, 2022, pp. 425–47, doi:<a
    href="https://doi.org/10.1007/s00454-022-00412-w">10.1007/s00454-022-00412-w</a>.
  short: R. Fulek, J. Kynčl, Discrete and Computational Geometry 68 (2022) 425–447.
date_created: 2022-07-17T22:01:56Z
date_published: 2022-09-01T00:00:00Z
date_updated: 2025-04-14T13:52:37Z
day: '01'
department:
- _id: UlWa
doi: 10.1007/s00454-022-00412-w
external_id:
  arxiv:
  - '1803.05085'
  isi:
  - '000825014500001'
intvolume: '        68'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1803.05085
month: '09'
oa: 1
oa_version: Preprint
page: 425-447
project:
- _id: 261FA626-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: M02281
  name: Eliminating intersections in drawings of graphs
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: '186'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: The Z2-Genus of Kuratowski minors
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 68
year: '2022'
...
---
_id: '12129'
abstract:
- lang: eng
  text: 'Given a finite point set P in general position in the plane, a full triangulation
    of P is a maximal straight-line embedded plane graph on P. A partial triangulation
    of P is a full triangulation of some subset P′ of P containing all extreme points
    in P. A bistellar flip on a partial triangulation either flips an edge (called
    edge flip), removes a non-extreme point of degree 3, or adds a point in P∖P′ as
    vertex of degree 3. The bistellar flip graph has all partial triangulations as
    vertices, and a pair of partial triangulations is adjacent if they can be obtained
    from one another by a bistellar flip. The edge flip graph is defined with full
    triangulations as vertices, and edge flips determining the adjacencies. Lawson
    showed in the early seventies that these graphs are connected. The goal of this
    paper is to investigate the structure of these graphs, with emphasis on their
    vertex connectivity. For sets P of n points in the plane in general position,
    we show that the edge flip graph is ⌈n/2−2⌉-vertex connected, and the bistellar
    flip graph is (n−3)-vertex connected; both results are tight. The latter bound
    matches the situation for the subfamily of regular triangulations (i.e., partial
    triangulations obtained by lifting the points to 3-space and projecting back the
    lower convex hull), where (n−3)-vertex connectivity has been known since the late
    eighties through the secondary polytope due to Gelfand, Kapranov, & Zelevinsky
    and Balinski’s Theorem. For the edge flip-graph, we additionally show that the
    vertex connectivity is at least as large as (and hence equal to) the minimum degree
    (i.e., the minimum number of flippable edges in any full triangulation), provided
    that n is large enough. Our methods also yield several other results: (i) The
    edge flip graph can be covered by graphs of polytopes of dimension ⌈n/2−2⌉ (products
    of associahedra) and the bistellar flip graph can be covered by graphs of polytopes
    of dimension n−3 (products of secondary polytopes). (ii) A partial triangulation
    is regular, if it has distance n−3 in the Hasse diagram of the partial order of
    partial subdivisions from the trivial subdivision. (iii) All partial triangulations
    of a point set are regular iff the partial order of partial subdivisions has height
    n−3. (iv) There are arbitrarily large sets P with non-regular partial triangulations
    and such that every proper subset has only regular triangulations, i.e., there
    are no small certificates for the existence of non-regular triangulations.'
acknowledgement: "This is a full and revised version of [38] (on partial triangulations)
  in Proceedings of the 36th Annual International Symposium on Computational Geometry
  (SoCG‘20) and of some of the results in [37] (on full triangulations) in Proceedings
  of the 31st Annual ACM-SIAM Symposium on Discrete Algorithms (SODA‘20).\r\nThis
  research started at the 11th Gremo’s Workshop on Open Problems (GWOP), Alp Sellamatt,
  Switzerland, June 24–28, 2013, motivated by a question posed by Filip Mori´c on
  full triangulations. Research was supported by the Swiss National Science Foundation
  within the collaborative DACH project Arrangements and Drawings as SNSF Project
  200021E-171681, and by IST Austria and Berlin Free University during a sabbatical
  stay of the second author. We thank Michael Joswig, Jesús De Loera, and Francisco
  Santos for helpful discussions on the topics of this paper, and Daniel Bertschinger
  and Valentin Stoppiello for carefully reading earlier versions and for many helpful
  comments.\r\nOpen access funding provided by the Swiss Federal Institute of Technology
  Zürich"
article_processing_charge: No
article_type: original
author:
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
- first_name: Emo
  full_name: Welzl, Emo
  last_name: Welzl
citation:
  ama: Wagner U, Welzl E. Connectivity of triangulation flip graphs in the plane.
    <i>Discrete &#38; Computational Geometry</i>. 2022;68(4):1227-1284. doi:<a href="https://doi.org/10.1007/s00454-022-00436-2">10.1007/s00454-022-00436-2</a>
  apa: Wagner, U., &#38; Welzl, E. (2022). Connectivity of triangulation flip graphs
    in the plane. <i>Discrete &#38; Computational Geometry</i>. Springer Nature. <a
    href="https://doi.org/10.1007/s00454-022-00436-2">https://doi.org/10.1007/s00454-022-00436-2</a>
  chicago: Wagner, Uli, and Emo Welzl. “Connectivity of Triangulation Flip Graphs
    in the Plane.” <i>Discrete &#38; Computational Geometry</i>. Springer Nature,
    2022. <a href="https://doi.org/10.1007/s00454-022-00436-2">https://doi.org/10.1007/s00454-022-00436-2</a>.
  ieee: U. Wagner and E. Welzl, “Connectivity of triangulation flip graphs in the
    plane,” <i>Discrete &#38; Computational Geometry</i>, vol. 68, no. 4. Springer
    Nature, pp. 1227–1284, 2022.
  ista: Wagner U, Welzl E. 2022. Connectivity of triangulation flip graphs in the
    plane. Discrete &#38; Computational Geometry. 68(4), 1227–1284.
  mla: Wagner, Uli, and Emo Welzl. “Connectivity of Triangulation Flip Graphs in the
    Plane.” <i>Discrete &#38; Computational Geometry</i>, vol. 68, no. 4, Springer
    Nature, 2022, pp. 1227–84, doi:<a href="https://doi.org/10.1007/s00454-022-00436-2">10.1007/s00454-022-00436-2</a>.
  short: U. Wagner, E. Welzl, Discrete &#38; Computational Geometry 68 (2022) 1227–1284.
corr_author: '1'
date_created: 2023-01-12T12:02:28Z
date_published: 2022-11-14T00:00:00Z
date_updated: 2025-07-10T11:54:56Z
day: '14'
ddc:
- '510'
department:
- _id: UlWa
doi: 10.1007/s00454-022-00436-2
external_id:
  isi:
  - '000883222200003'
file:
- access_level: open_access
  checksum: 307e879d09e52eddf5b225d0aaa9213a
  content_type: application/pdf
  creator: dernst
  date_created: 2023-01-23T11:10:03Z
  date_updated: 2023-01-23T11:10:03Z
  file_id: '12345'
  file_name: 2022_DiscreteCompGeometry_Wagner.pdf
  file_size: 1747581
  relation: main_file
  success: 1
file_date_updated: 2023-01-23T11:10:03Z
has_accepted_license: '1'
intvolume: '        68'
isi: 1
issue: '4'
keyword:
- Computational Theory and Mathematics
- Discrete Mathematics and Combinatorics
- Geometry and Topology
- Theoretical Computer Science
language:
- iso: eng
month: '11'
oa: 1
oa_version: Published Version
page: 1227-1284
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  record:
  - id: '7807'
    relation: earlier_version
    status: public
  - id: '7990'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Connectivity of triangulation flip graphs in the plane
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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 68
year: '2022'
...
---
_id: '10773'
abstract:
- lang: eng
  text: The Voronoi tessellation in Rd is defined by locally minimizing the power
    distance to given weighted points. Symmetrically, the Delaunay mosaic can be defined
    by locally maximizing the negative power distance to other such points. We prove
    that the average of the two piecewise quadratic functions is piecewise linear,
    and that all three functions have the same critical points and values. Discretizing
    the two piecewise quadratic functions, we get the alpha shapes as sublevel sets
    of the discrete function on the Delaunay mosaic, and analogous shapes as superlevel
    sets of the discrete function on the Voronoi tessellation. For the same non-critical
    value, the corresponding shapes are disjoint, separated by a narrow channel that
    contains no critical points but the entire level set of the piecewise linear function.
acknowledgement: Open access funding provided by the Institute of Science and Technology
  (IST Austria).
article_processing_charge: Yes (via OA deal)
article_type: original
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: 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
  last_name: Saghafian
citation:
  ama: Biswas R, Cultrera di Montesano S, Edelsbrunner H, Saghafian M. Continuous
    and discrete radius functions on Voronoi tessellations and Delaunay mosaics. <i>Discrete
    and Computational Geometry</i>. 2022;67:811-842. doi:<a href="https://doi.org/10.1007/s00454-022-00371-2">10.1007/s00454-022-00371-2</a>
  apa: Biswas, R., Cultrera di Montesano, S., Edelsbrunner, H., &#38; Saghafian, M.
    (2022). Continuous and discrete radius functions on Voronoi tessellations and
    Delaunay mosaics. <i>Discrete and Computational Geometry</i>. Springer Nature.
    <a href="https://doi.org/10.1007/s00454-022-00371-2">https://doi.org/10.1007/s00454-022-00371-2</a>
  chicago: Biswas, Ranita, Sebastiano Cultrera di Montesano, Herbert Edelsbrunner,
    and Morteza Saghafian. “Continuous and Discrete Radius Functions on Voronoi Tessellations
    and Delaunay Mosaics.” <i>Discrete and Computational Geometry</i>. Springer Nature,
    2022. <a href="https://doi.org/10.1007/s00454-022-00371-2">https://doi.org/10.1007/s00454-022-00371-2</a>.
  ieee: R. Biswas, S. Cultrera di Montesano, H. Edelsbrunner, and M. Saghafian, “Continuous
    and discrete radius functions on Voronoi tessellations and Delaunay mosaics,”
    <i>Discrete and Computational Geometry</i>, vol. 67. Springer Nature, pp. 811–842,
    2022.
  ista: Biswas R, Cultrera di Montesano S, Edelsbrunner H, Saghafian M. 2022. Continuous
    and discrete radius functions on Voronoi tessellations and Delaunay mosaics. Discrete
    and Computational Geometry. 67, 811–842.
  mla: Biswas, Ranita, et al. “Continuous and Discrete Radius Functions on Voronoi
    Tessellations and Delaunay Mosaics.” <i>Discrete and Computational Geometry</i>,
    vol. 67, Springer Nature, 2022, pp. 811–42, doi:<a href="https://doi.org/10.1007/s00454-022-00371-2">10.1007/s00454-022-00371-2</a>.
  short: R. Biswas, S. Cultrera di Montesano, H. Edelsbrunner, M. Saghafian, Discrete
    and Computational Geometry 67 (2022) 811–842.
corr_author: '1'
date_created: 2022-02-20T23:01:34Z
date_published: 2022-04-01T00:00:00Z
date_updated: 2024-10-09T21:01:38Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-022-00371-2
external_id:
  isi:
  - '000752175300002'
file:
- access_level: open_access
  checksum: 9383d3b70561bacee905e335dc922680
  content_type: application/pdf
  creator: dernst
  date_created: 2022-08-02T06:07:55Z
  date_updated: 2022-08-02T06:07:55Z
  file_id: '11718'
  file_name: 2022_DiscreteCompGeometry_Biswas.pdf
  file_size: 2518111
  relation: main_file
  success: 1
file_date_updated: 2022-08-02T06:07:55Z
has_accepted_license: '1'
intvolume: '        67'
isi: 1
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
page: 811-842
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Continuous and discrete radius functions on Voronoi tessellations and 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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 67
year: '2022'
...
---
_id: '10776'
abstract:
- lang: eng
  text: 'Let K be a convex body in Rn (i.e., a compact convex set with nonempty interior).
    Given a point p in the interior of K, a hyperplane h passing through p is called
    barycentric if p is the barycenter of K∩h. In 1961, Grünbaum raised the question
    whether, for every K, there exists an interior point p through which there are
    at least n+1 distinct barycentric hyperplanes. Two years later, this was seemingly
    resolved affirmatively by showing that this is the case if p=p0 is the point of
    maximal depth in K. However, while working on a related question, we noticed that
    one of the auxiliary claims in the proof is incorrect. Here, we provide a counterexample;
    this re-opens Grünbaum’s question. It follows from known results that for n≥2,
    there are always at least three distinct barycentric cuts through the point p0∈K
    of maximal depth. Using tools related to Morse theory we are able to improve this
    bound: four distinct barycentric cuts through p0 are guaranteed if n≥3.'
acknowledgement: The work by Zuzana Patáková has been partially supported by Charles
  University Research Center Program No. UNCE/SCI/022, and part of it was done during
  her research stay at IST Austria. The work by Martin Tancer is supported by the
  GAČR Grant 19-04113Y and by the Charles University Projects PRIMUS/17/SCI/3 and
  UNCE/SCI/004.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Zuzana
  full_name: Patakova, Zuzana
  id: 48B57058-F248-11E8-B48F-1D18A9856A87
  last_name: Patakova
  orcid: 0000-0002-3975-1683
- first_name: Martin
  full_name: Tancer, Martin
  last_name: Tancer
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
citation:
  ama: Patakova Z, Tancer M, Wagner U. Barycentric cuts through a convex body. <i>Discrete
    and Computational Geometry</i>. 2022;68:1133-1154. doi:<a href="https://doi.org/10.1007/s00454-021-00364-7">10.1007/s00454-021-00364-7</a>
  apa: Patakova, Z., Tancer, M., &#38; Wagner, U. (2022). Barycentric cuts through
    a convex body. <i>Discrete and Computational Geometry</i>. Springer Nature. <a
    href="https://doi.org/10.1007/s00454-021-00364-7">https://doi.org/10.1007/s00454-021-00364-7</a>
  chicago: Patakova, Zuzana, Martin Tancer, and Uli Wagner. “Barycentric Cuts through
    a Convex Body.” <i>Discrete and Computational Geometry</i>. Springer Nature, 2022.
    <a href="https://doi.org/10.1007/s00454-021-00364-7">https://doi.org/10.1007/s00454-021-00364-7</a>.
  ieee: Z. Patakova, M. Tancer, and U. Wagner, “Barycentric cuts through a convex
    body,” <i>Discrete and Computational Geometry</i>, vol. 68. Springer Nature, pp.
    1133–1154, 2022.
  ista: Patakova Z, Tancer M, Wagner U. 2022. Barycentric cuts through a convex body.
    Discrete and Computational Geometry. 68, 1133–1154.
  mla: Patakova, Zuzana, et al. “Barycentric Cuts through a Convex Body.” <i>Discrete
    and Computational Geometry</i>, vol. 68, Springer Nature, 2022, pp. 1133–54, doi:<a
    href="https://doi.org/10.1007/s00454-021-00364-7">10.1007/s00454-021-00364-7</a>.
  short: Z. Patakova, M. Tancer, U. Wagner, Discrete and Computational Geometry 68
    (2022) 1133–1154.
date_created: 2022-02-20T23:01:35Z
date_published: 2022-12-01T00:00:00Z
date_updated: 2023-08-02T14:38:58Z
day: '01'
department:
- _id: UlWa
doi: 10.1007/s00454-021-00364-7
external_id:
  arxiv:
  - '2003.13536'
  isi:
  - '000750681500001'
intvolume: '        68'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2003.13536
month: '12'
oa: 1
oa_version: Preprint
page: 1133-1154
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Barycentric cuts through a convex body
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 68
year: '2022'
...
---
_id: '11446'
abstract:
- lang: eng
  text: Suppose that n is not a prime power and not twice a prime power. We prove
    that for any Hausdorff compactum X with a free action of the symmetric group Sn,
    there exists an Sn-equivariant map X→Rn whose image avoids the diagonal {(x,x,…,x)∈Rn∣x∈R}.
    Previously, the special cases of this statement for certain X were usually proved
    using the equivartiant obstruction theory. Such calculations are difficult and
    may become infeasible past the first (primary) obstruction. We take a different
    approach which allows us to prove the vanishing of all obstructions simultaneously.
    The essential step in the proof is classifying the possible degrees of Sn-equivariant
    maps from the boundary ∂Δn−1 of (n−1)-simplex to itself. Existence of equivariant
    maps between spaces is important for many questions arising from discrete mathematics
    and geometry, such as Kneser’s conjecture, the Square Peg conjecture, the Splitting
    Necklace problem, and the Topological Tverberg conjecture, etc. We demonstrate
    the utility of our result applying it to one such question, a specific instance
    of envy-free division problem.
acknowledgement: S. Avvakumov has received funding from the European Research Council
  under the European Union’s Seventh Framework Programme ERC Grant agreement ERC StG
  716424–CASe. S. Kudrya was supported by the Austrian Academic Exchange Service (OeAD),
  ICM-2019-13577.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
  orcid: 0000-0002-7840-5062
- first_name: Sergey
  full_name: Kudrya, Sergey
  id: ecf01965-d252-11ea-95a5-8ada5f6c6a67
  last_name: Kudrya
citation:
  ama: Avvakumov S, Kudrya S. Vanishing of all equivariant obstructions and the mapping
    degree. <i>Discrete &#38; Computational Geometry</i>. 2021;66(3):1202-1216. doi:<a
    href="https://doi.org/10.1007/s00454-021-00299-z">10.1007/s00454-021-00299-z</a>
  apa: Avvakumov, S., &#38; Kudrya, S. (2021). Vanishing of all equivariant obstructions
    and the mapping degree. <i>Discrete &#38; Computational Geometry</i>. Springer
    Nature. <a href="https://doi.org/10.1007/s00454-021-00299-z">https://doi.org/10.1007/s00454-021-00299-z</a>
  chicago: Avvakumov, Sergey, and Sergey Kudrya. “Vanishing of All Equivariant Obstructions
    and the Mapping Degree.” <i>Discrete &#38; Computational Geometry</i>. Springer
    Nature, 2021. <a href="https://doi.org/10.1007/s00454-021-00299-z">https://doi.org/10.1007/s00454-021-00299-z</a>.
  ieee: S. Avvakumov and S. Kudrya, “Vanishing of all equivariant obstructions and
    the mapping degree,” <i>Discrete &#38; Computational Geometry</i>, vol. 66, no.
    3. Springer Nature, pp. 1202–1216, 2021.
  ista: Avvakumov S, Kudrya S. 2021. Vanishing of all equivariant obstructions and
    the mapping degree. Discrete &#38; Computational Geometry. 66(3), 1202–1216.
  mla: Avvakumov, Sergey, and Sergey Kudrya. “Vanishing of All Equivariant Obstructions
    and the Mapping Degree.” <i>Discrete &#38; Computational Geometry</i>, vol. 66,
    no. 3, Springer Nature, 2021, pp. 1202–16, doi:<a href="https://doi.org/10.1007/s00454-021-00299-z">10.1007/s00454-021-00299-z</a>.
  short: S. Avvakumov, S. Kudrya, Discrete &#38; Computational Geometry 66 (2021)
    1202–1216.
corr_author: '1'
date_created: 2022-06-17T08:45:15Z
date_published: 2021-10-01T00:00:00Z
date_updated: 2025-04-14T09:10:06Z
day: '01'
doi: 10.1007/s00454-021-00299-z
extern: '1'
external_id:
  arxiv:
  - '1910.12628'
intvolume: '        66'
issue: '3'
keyword:
- Computational Theory and Mathematics
- Discrete Mathematics and Combinatorics
- Geometry and Topology
- Theoretical Computer Science
language:
- iso: eng
month: '10'
oa_version: Preprint
page: 1202-1216
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  record:
  - id: '8182'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Vanishing of all equivariant obstructions and the mapping degree
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 66
year: '2021'
...
---
_id: '7905'
abstract:
- lang: eng
  text: We investigate a sheaf-theoretic interpretation of stratification learning
    from geometric and topological perspectives. Our main result is the construction
    of stratification learning algorithms framed in terms of a sheaf on a partially
    ordered set with the Alexandroff topology. We prove that the resulting decomposition
    is the unique minimal stratification for which the strata are homogeneous and
    the given sheaf is constructible. In particular, when we choose to work with the
    local homology sheaf, our algorithm gives an alternative to the local homology
    transfer algorithm given in Bendich et al. (Proceedings of the 23rd Annual ACM-SIAM
    Symposium on Discrete Algorithms, pp. 1355–1370, ACM, New York, 2012), and the
    cohomology stratification algorithm given in Nanda (Found. Comput. Math. 20(2),
    195–222, 2020). Additionally, we give examples of stratifications based on the
    geometric techniques of Breiding et al. (Rev. Mat. Complut. 31(3), 545–593, 2018),
    illustrating how the sheaf-theoretic approach can be used to study stratifications
    from both topological and geometric perspectives. This approach also points toward
    future applications of sheaf theory in the study of topological data analysis
    by illustrating the utility of the language of sheaf theory in generalizing existing
    algorithms.
acknowledgement: Open access funding provided by Institute of Science and Technology
  (IST Austria). This work was partially supported by NSF IIS-1513616 and NSF ABI-1661375.
  The authors would like to thank the anonymous referees for their insightful comments.
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: Bei
  full_name: Wang, Bei
  last_name: Wang
citation:
  ama: Brown A, Wang B. Sheaf-theoretic stratification learning from geometric and
    topological perspectives. <i>Discrete and Computational Geometry</i>. 2021;65:1166-1198.
    doi:<a href="https://doi.org/10.1007/s00454-020-00206-y">10.1007/s00454-020-00206-y</a>
  apa: Brown, A., &#38; Wang, B. (2021). Sheaf-theoretic stratification learning from
    geometric and topological perspectives. <i>Discrete and Computational Geometry</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s00454-020-00206-y">https://doi.org/10.1007/s00454-020-00206-y</a>
  chicago: Brown, Adam, and Bei Wang. “Sheaf-Theoretic Stratification Learning from
    Geometric and Topological Perspectives.” <i>Discrete and Computational Geometry</i>.
    Springer Nature, 2021. <a href="https://doi.org/10.1007/s00454-020-00206-y">https://doi.org/10.1007/s00454-020-00206-y</a>.
  ieee: A. Brown and B. Wang, “Sheaf-theoretic stratification learning from geometric
    and topological perspectives,” <i>Discrete and Computational Geometry</i>, vol.
    65. Springer Nature, pp. 1166–1198, 2021.
  ista: Brown A, Wang B. 2021. Sheaf-theoretic stratification learning from geometric
    and topological perspectives. Discrete and Computational Geometry. 65, 1166–1198.
  mla: Brown, Adam, and Bei Wang. “Sheaf-Theoretic Stratification Learning from Geometric
    and Topological Perspectives.” <i>Discrete and Computational Geometry</i>, vol.
    65, Springer Nature, 2021, pp. 1166–98, doi:<a href="https://doi.org/10.1007/s00454-020-00206-y">10.1007/s00454-020-00206-y</a>.
  short: A. Brown, B. Wang, Discrete and Computational Geometry 65 (2021) 1166–1198.
corr_author: '1'
date_created: 2020-05-30T10:26:04Z
date_published: 2021-06-01T00:00:00Z
date_updated: 2025-04-15T06:53:15Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-020-00206-y
external_id:
  arxiv:
  - '1712.07734'
  isi:
  - '000536324700001'
file:
- access_level: open_access
  checksum: 487a84ea5841b75f04f66d7ebd71b67e
  content_type: application/pdf
  creator: dernst
  date_created: 2020-11-25T09:06:41Z
  date_updated: 2020-11-25T09:06:41Z
  file_id: '8803'
  file_name: 2020_DiscreteCompGeometry_Brown.pdf
  file_size: 1013730
  relation: main_file
  success: 1
file_date_updated: 2020-11-25T09:06:41Z
has_accepted_license: '1'
intvolume: '        65'
isi: 1
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: 1166-1198
project:
- _id: B67AFEDC-15C9-11EA-A837-991A96BB2854
  name: IST Austria Open Access Fund
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Sheaf-theoretic stratification learning from geometric and topological perspectives
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: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 65
year: '2021'
...
---
_id: '8248'
abstract:
- lang: eng
  text: 'We consider the following setting: suppose that we are given a manifold M
    in Rd with positive reach. Moreover assume that we have an embedded simplical
    complex A without boundary, whose vertex set lies on the manifold, is sufficiently
    dense and such that all simplices in A have sufficient quality. We prove that
    if, locally, interiors of the projection of the simplices onto the tangent space
    do not intersect, then A is a triangulation of the manifold, that is, they are
    homeomorphic.'
acknowledgement: "Open access funding provided by the Institute of Science and Technology
  (IST Austria). Arijit Ghosh is supported by the Ramanujan Fellowship (No. SB/S2/RJN-064/2015),
  India.\r\nThis work has been funded by the European Research Council under the European
  Union’s ERC Grant Agreement number 339025 GUDHI (Algorithmic Foundations of Geometric
  Understanding in Higher Dimensions). The third author is supported by Ramanujan
  Fellowship (No. SB/S2/RJN-064/2015), India. The fifth author also received funding
  from the European Union’s Horizon 2020 research and innovation programme under the
  Marie Skłodowska-Curie Grant Agreement No. 754411."
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Jean-Daniel
  full_name: Boissonnat, Jean-Daniel
  last_name: Boissonnat
- first_name: Ramsay
  full_name: Dyer, Ramsay
  last_name: Dyer
- first_name: Arijit
  full_name: Ghosh, Arijit
  last_name: Ghosh
- first_name: Andre
  full_name: Lieutier, Andre
  last_name: Lieutier
- first_name: Mathijs
  full_name: Wintraecken, Mathijs
  id: 307CFBC8-F248-11E8-B48F-1D18A9856A87
  last_name: Wintraecken
  orcid: 0000-0002-7472-2220
citation:
  ama: Boissonnat J-D, Dyer R, Ghosh A, Lieutier A, Wintraecken M. Local conditions
    for triangulating submanifolds of Euclidean space. <i>Discrete and Computational
    Geometry</i>. 2021;66:666-686. doi:<a href="https://doi.org/10.1007/s00454-020-00233-9">10.1007/s00454-020-00233-9</a>
  apa: Boissonnat, J.-D., Dyer, R., Ghosh, A., Lieutier, A., &#38; Wintraecken, M.
    (2021). Local conditions for triangulating submanifolds of Euclidean space. <i>Discrete
    and Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-020-00233-9">https://doi.org/10.1007/s00454-020-00233-9</a>
  chicago: Boissonnat, Jean-Daniel, Ramsay Dyer, Arijit Ghosh, Andre Lieutier, and
    Mathijs Wintraecken. “Local Conditions for Triangulating Submanifolds of Euclidean
    Space.” <i>Discrete and Computational Geometry</i>. Springer Nature, 2021. <a
    href="https://doi.org/10.1007/s00454-020-00233-9">https://doi.org/10.1007/s00454-020-00233-9</a>.
  ieee: J.-D. Boissonnat, R. Dyer, A. Ghosh, A. Lieutier, and M. Wintraecken, “Local
    conditions for triangulating submanifolds of Euclidean space,” <i>Discrete and
    Computational Geometry</i>, vol. 66. Springer Nature, pp. 666–686, 2021.
  ista: Boissonnat J-D, Dyer R, Ghosh A, Lieutier A, Wintraecken M. 2021. Local conditions
    for triangulating submanifolds of Euclidean space. Discrete and Computational
    Geometry. 66, 666–686.
  mla: Boissonnat, Jean-Daniel, et al. “Local Conditions for Triangulating Submanifolds
    of Euclidean Space.” <i>Discrete and Computational Geometry</i>, vol. 66, Springer
    Nature, 2021, pp. 666–86, doi:<a href="https://doi.org/10.1007/s00454-020-00233-9">10.1007/s00454-020-00233-9</a>.
  short: J.-D. Boissonnat, R. Dyer, A. Ghosh, A. Lieutier, M. Wintraecken, Discrete
    and Computational Geometry 66 (2021) 666–686.
corr_author: '1'
date_created: 2020-08-11T07:11:51Z
date_published: 2021-09-01T00:00:00Z
date_updated: 2025-04-14T07:44:05Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1007/s00454-020-00233-9
ec_funded: 1
external_id:
  isi:
  - '000558119300001'
has_accepted_license: '1'
intvolume: '        66'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1007/s00454-020-00233-9
month: '09'
oa: 1
oa_version: Published Version
page: 666-686
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Local conditions for triangulating submanifolds of Euclidean space
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: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 66
year: '2021'
...
---
_id: '8338'
abstract:
- lang: eng
  text: Canonical parametrisations of classical confocal coordinate systems are introduced
    and exploited to construct non-planar analogues of incircular (IC) nets on individual
    quadrics and systems of confocal quadrics. Intimate connections with classical
    deformations of quadrics that are isometric along asymptotic lines and circular
    cross-sections of quadrics are revealed. The existence of octahedral webs of surfaces
    of Blaschke type generated by asymptotic and characteristic lines that are diagonally
    related to lines of curvature is proved theoretically and established constructively.
    Appropriate samplings (grids) of these webs lead to three-dimensional extensions
    of non-planar IC nets. Three-dimensional octahedral grids composed of planes and
    spatially extending (checkerboard) IC-nets are shown to arise in connection with
    systems of confocal quadrics in Minkowski space. In this context, the Laguerre
    geometric notion of conical octahedral grids of planes is introduced. The latter
    generalise the octahedral grids derived from systems of confocal quadrics in Minkowski
    space. An explicit construction of conical octahedral grids is presented. The
    results are accompanied by various illustrations which are based on the explicit
    formulae provided by the theory.
acknowledgement: This research was supported by the DFG Collaborative Research Center
  TRR 109 “Discretization in Geometry and Dynamics”. W.K.S. was also supported by
  the Australian Research Council (DP1401000851). A.V.A. was also supported by the
  European Research Council (ERC) under the European Union’s Horizon 2020 research
  and innovation programme (Grant Agreement No. 78818 Alpha).
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Alexander I.
  full_name: Bobenko, Alexander I.
  last_name: Bobenko
- first_name: Wolfgang K.
  full_name: Schief, Wolfgang K.
  last_name: Schief
- first_name: Jan
  full_name: Techter, Jan
  last_name: Techter
citation:
  ama: Akopyan A, Bobenko AI, Schief WK, Techter J. On mutually diagonal nets on (confocal)
    quadrics and 3-dimensional webs. <i>Discrete and Computational Geometry</i>. 2021;66:938-976.
    doi:<a href="https://doi.org/10.1007/s00454-020-00240-w">10.1007/s00454-020-00240-w</a>
  apa: Akopyan, A., Bobenko, A. I., Schief, W. K., &#38; Techter, J. (2021). On mutually
    diagonal nets on (confocal) quadrics and 3-dimensional webs. <i>Discrete and Computational
    Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-020-00240-w">https://doi.org/10.1007/s00454-020-00240-w</a>
  chicago: Akopyan, Arseniy, Alexander I. Bobenko, Wolfgang K. Schief, and Jan Techter.
    “On Mutually Diagonal Nets on (Confocal) Quadrics and 3-Dimensional Webs.” <i>Discrete
    and Computational Geometry</i>. Springer Nature, 2021. <a href="https://doi.org/10.1007/s00454-020-00240-w">https://doi.org/10.1007/s00454-020-00240-w</a>.
  ieee: A. Akopyan, A. I. Bobenko, W. K. Schief, and J. Techter, “On mutually diagonal
    nets on (confocal) quadrics and 3-dimensional webs,” <i>Discrete and Computational
    Geometry</i>, vol. 66. Springer Nature, pp. 938–976, 2021.
  ista: Akopyan A, Bobenko AI, Schief WK, Techter J. 2021. On mutually diagonal nets
    on (confocal) quadrics and 3-dimensional webs. Discrete and Computational Geometry.
    66, 938–976.
  mla: Akopyan, Arseniy, et al. “On Mutually Diagonal Nets on (Confocal) Quadrics
    and 3-Dimensional Webs.” <i>Discrete and Computational Geometry</i>, vol. 66,
    Springer Nature, 2021, pp. 938–76, doi:<a href="https://doi.org/10.1007/s00454-020-00240-w">10.1007/s00454-020-00240-w</a>.
  short: A. Akopyan, A.I. Bobenko, W.K. Schief, J. Techter, Discrete and Computational
    Geometry 66 (2021) 938–976.
date_created: 2020-09-06T22:01:13Z
date_published: 2021-10-01T00:00:00Z
date_updated: 2025-04-14T07:48:36Z
day: '01'
department:
- _id: HeEd
doi: 10.1007/s00454-020-00240-w
ec_funded: 1
external_id:
  arxiv:
  - '1908.00856'
  isi:
  - '000564488500002'
intvolume: '        66'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1908.00856
month: '10'
oa: 1
oa_version: Preprint
page: 938-976
project:
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
publication: Discrete and Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: On mutually diagonal nets on (confocal) quadrics and 3-dimensional webs
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 66
year: '2021'
...
---
_id: '8940'
abstract:
- lang: eng
  text: We quantise Whitney’s construction to prove the existence of a triangulation
    for any C^2 manifold, so that we get an algorithm with explicit bounds. We also
    give a new elementary proof, which is completely geometric.
acknowledgement: This work has been funded by the European Research Council under
  the European Union’s ERC Grant Agreement Number 339025 GUDHI (Algorithmic Foundations
  of Geometric Understanding in Higher Dimensions). The third author also received
  funding from the European Union’s Horizon 2020 research and innovation programme
  under the Marie Skłodowska-Curie Grant Agreement No. 754411. Open access funding
  provided by the Institute of Science and Technology (IST Austria).
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Jean-Daniel
  full_name: Boissonnat, Jean-Daniel
  last_name: Boissonnat
- first_name: Siargey
  full_name: Kachanovich, Siargey
  last_name: Kachanovich
- first_name: Mathijs
  full_name: Wintraecken, Mathijs
  id: 307CFBC8-F248-11E8-B48F-1D18A9856A87
  last_name: Wintraecken
  orcid: 0000-0002-7472-2220
citation:
  ama: 'Boissonnat J-D, Kachanovich S, Wintraecken M. Triangulating submanifolds:
    An elementary and quantified version of Whitney’s method. <i>Discrete &#38; Computational
    Geometry</i>. 2021;66(1):386-434. doi:<a href="https://doi.org/10.1007/s00454-020-00250-8">10.1007/s00454-020-00250-8</a>'
  apa: 'Boissonnat, J.-D., Kachanovich, S., &#38; Wintraecken, M. (2021). Triangulating
    submanifolds: An elementary and quantified version of Whitney’s method. <i>Discrete
    &#38; Computational Geometry</i>. Springer Nature. <a href="https://doi.org/10.1007/s00454-020-00250-8">https://doi.org/10.1007/s00454-020-00250-8</a>'
  chicago: 'Boissonnat, Jean-Daniel, Siargey Kachanovich, and Mathijs Wintraecken.
    “Triangulating Submanifolds: An Elementary and Quantified Version of Whitney’s
    Method.” <i>Discrete &#38; Computational Geometry</i>. Springer Nature, 2021.
    <a href="https://doi.org/10.1007/s00454-020-00250-8">https://doi.org/10.1007/s00454-020-00250-8</a>.'
  ieee: 'J.-D. Boissonnat, S. Kachanovich, and M. Wintraecken, “Triangulating submanifolds:
    An elementary and quantified version of Whitney’s method,” <i>Discrete &#38; Computational
    Geometry</i>, vol. 66, no. 1. Springer Nature, pp. 386–434, 2021.'
  ista: 'Boissonnat J-D, Kachanovich S, Wintraecken M. 2021. Triangulating submanifolds:
    An elementary and quantified version of Whitney’s method. Discrete &#38; Computational
    Geometry. 66(1), 386–434.'
  mla: 'Boissonnat, Jean-Daniel, et al. “Triangulating Submanifolds: An Elementary
    and Quantified Version of Whitney’s Method.” <i>Discrete &#38; Computational Geometry</i>,
    vol. 66, no. 1, Springer Nature, 2021, pp. 386–434, doi:<a href="https://doi.org/10.1007/s00454-020-00250-8">10.1007/s00454-020-00250-8</a>.'
  short: J.-D. Boissonnat, S. Kachanovich, M. Wintraecken, Discrete &#38; Computational
    Geometry 66 (2021) 386–434.
corr_author: '1'
date_created: 2020-12-12T11:07:02Z
date_published: 2021-07-01T00:00:00Z
date_updated: 2025-04-14T07:43:50Z
day: '01'
ddc:
- '516'
department:
- _id: HeEd
doi: 10.1007/s00454-020-00250-8
ec_funded: 1
external_id:
  isi:
  - '000597770300001'
file:
- access_level: open_access
  checksum: c848986091e56699dc12de85adb1e39c
  content_type: application/pdf
  creator: kschuh
  date_created: 2021-08-06T09:52:29Z
  date_updated: 2021-08-06T09:52:29Z
  file_id: '9795'
  file_name: 2021_DescreteCompGeopmetry_Boissonnat.pdf
  file_size: 983307
  relation: main_file
  success: 1
file_date_updated: 2021-08-06T09:52:29Z
has_accepted_license: '1'
intvolume: '        66'
isi: 1
issue: '1'
keyword:
- Theoretical Computer Science
- Computational Theory and Mathematics
- Geometry and Topology
- Discrete Mathematics and Combinatorics
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: 386-434
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Discrete & Computational Geometry
publication_identifier:
  eissn:
  - 1432-0444
  issn:
  - 0179-5376
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Triangulating submanifolds: An elementary and quantified version of Whitney’s
  method'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 66
year: '2021'
...
