---
_id: '10220'
abstract:
- lang: eng
  text: "We study conditions under which a finite simplicial complex K can be mapped
    to ℝd without higher-multiplicity intersections. An almost r-embedding is a map
    f: K → ℝd such that the images of any r pairwise disjoint simplices of K do not
    have a common point. We show that if r is not a prime power and d ≥ 2r + 1, then
    there is a counterexample to the topological Tverberg conjecture, i.e., there
    is an almost r-embedding of the (d +1)(r − 1)-simplex in ℝd. This improves on
    previous constructions of counterexamples (for d ≥ 3r) based on a series of papers
    by M. Özaydin, M. Gromov, P. Blagojević, F. Frick, G. Ziegler, and the second
    and fourth present authors.\r\n\r\nThe counterexamples are obtained by proving
    the following algebraic criterion in codimension 2: If r ≥ 3 and if K is a finite
    2(r − 1)-complex, then there exists an almost r-embedding K → ℝ2r if and only
    if there exists a general position PL map f: K → ℝ2r such that the algebraic intersection
    number of the f-images of any r pairwise disjoint simplices of K is zero. This
    result can be restated in terms of a cohomological obstruction and extends an
    analogous codimension 3 criterion by the second and fourth authors. As another
    application, we classify ornaments f: S3 ⊔ S3 ⊔ S3 → ℝ5 up to ornament concordance.\r\n\r\nIt
    follows from work of M. Freedman, V. Krushkal and P. Teichner that the analogous
    criterion for r = 2 is false. We prove a lemma on singular higher-dimensional
    Borromean rings, yielding an elementary proof of the counterexample."
acknowledgement: Research supported by the Swiss National Science Foundation (Project
  SNSF-PP00P2-138948), by the Austrian Science Fund (FWF Project P31312-N35), by the
  Russian Foundation for Basic Research (Grants No. 15-01-06302 and 19-01-00169),
  by a Simons-IUM Fellowship, and by the D. Zimin Dynasty Foundation Grant. We would
  like to thank E. Alkin, A. Klyachko, V. Krushkal, S. Melikhov, M. Tancer, P. Teichner
  and anonymous referees for helpful comments and discussions.
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
- first_name: Isaac
  full_name: Mabillard, Isaac
  id: 32BF9DAA-F248-11E8-B48F-1D18A9856A87
  last_name: Mabillard
- first_name: Arkadiy B.
  full_name: Skopenkov, Arkadiy B.
  last_name: Skopenkov
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
citation:
  ama: Avvakumov S, Mabillard I, Skopenkov AB, Wagner U. Eliminating higher-multiplicity
    intersections. III. Codimension 2. <i>Israel Journal of Mathematics</i>. 2021;245:501–534.
    doi:<a href="https://doi.org/10.1007/s11856-021-2216-z">10.1007/s11856-021-2216-z</a>
  apa: Avvakumov, S., Mabillard, I., Skopenkov, A. B., &#38; Wagner, U. (2021). Eliminating
    higher-multiplicity intersections. III. Codimension 2. <i>Israel Journal of Mathematics</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s11856-021-2216-z">https://doi.org/10.1007/s11856-021-2216-z</a>
  chicago: Avvakumov, Sergey, Isaac Mabillard, Arkadiy B. Skopenkov, and Uli Wagner.
    “Eliminating Higher-Multiplicity Intersections. III. Codimension 2.” <i>Israel
    Journal of Mathematics</i>. Springer Nature, 2021. <a href="https://doi.org/10.1007/s11856-021-2216-z">https://doi.org/10.1007/s11856-021-2216-z</a>.
  ieee: S. Avvakumov, I. Mabillard, A. B. Skopenkov, and U. Wagner, “Eliminating higher-multiplicity
    intersections. III. Codimension 2,” <i>Israel Journal of Mathematics</i>, vol.
    245. Springer Nature, pp. 501–534, 2021.
  ista: Avvakumov S, Mabillard I, Skopenkov AB, Wagner U. 2021. Eliminating higher-multiplicity
    intersections. III. Codimension 2. Israel Journal of Mathematics. 245, 501–534.
  mla: Avvakumov, Sergey, et al. “Eliminating Higher-Multiplicity Intersections. III.
    Codimension 2.” <i>Israel Journal of Mathematics</i>, vol. 245, Springer Nature,
    2021, pp. 501–534, doi:<a href="https://doi.org/10.1007/s11856-021-2216-z">10.1007/s11856-021-2216-z</a>.
  short: S. Avvakumov, I. Mabillard, A.B. Skopenkov, U. Wagner, Israel Journal of
    Mathematics 245 (2021) 501–534.
date_created: 2021-11-07T23:01:24Z
date_published: 2021-10-30T00:00:00Z
date_updated: 2023-08-14T11:43:55Z
day: '30'
department:
- _id: UlWa
doi: 10.1007/s11856-021-2216-z
external_id:
  arxiv:
  - '1511.03501'
  isi:
  - '000712942100013'
intvolume: '       245'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1511.03501
month: '10'
oa: 1
oa_version: Preprint
page: '501–534 '
project:
- _id: 26611F5C-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P31312
  name: Algorithms for Embeddings and Homotopy Theory
publication: Israel Journal of Mathematics
publication_identifier:
  eissn:
  - 1565-8511
  issn:
  - 0021-2172
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
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  - id: '8183'
    relation: earlier_version
    status: public
  - id: '9308'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Eliminating higher-multiplicity intersections. III. Codimension 2
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 245
year: '2021'
...
---
_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
- 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.
date_created: 2022-06-17T08:45:15Z
date_published: 2021-10-01T00:00:00Z
date_updated: 2023-02-23T13:26:41Z
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: '9308'
acknowledgement: This research was carried out with the support of the Russian Foundation
  for Basic Research(grant no. 19-01-00169)
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
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
- first_name: Isaac
  full_name: Mabillard, Isaac
  id: 32BF9DAA-F248-11E8-B48F-1D18A9856A87
  last_name: Mabillard
- first_name: A. B.
  full_name: Skopenkov, A. B.
  last_name: Skopenkov
citation:
  ama: Avvakumov S, Wagner U, Mabillard I, Skopenkov AB. Eliminating higher-multiplicity
    intersections, III. Codimension 2. <i>Russian Mathematical Surveys</i>. 2020;75(6):1156-1158.
    doi:<a href="https://doi.org/10.1070/RM9943">10.1070/RM9943</a>
  apa: Avvakumov, S., Wagner, U., Mabillard, I., &#38; Skopenkov, A. B. (2020). Eliminating
    higher-multiplicity intersections, III. Codimension 2. <i>Russian Mathematical
    Surveys</i>. IOP Publishing. <a href="https://doi.org/10.1070/RM9943">https://doi.org/10.1070/RM9943</a>
  chicago: Avvakumov, Sergey, Uli Wagner, Isaac Mabillard, and A. B. Skopenkov. “Eliminating
    Higher-Multiplicity Intersections, III. Codimension 2.” <i>Russian Mathematical
    Surveys</i>. IOP Publishing, 2020. <a href="https://doi.org/10.1070/RM9943">https://doi.org/10.1070/RM9943</a>.
  ieee: S. Avvakumov, U. Wagner, I. Mabillard, and A. B. Skopenkov, “Eliminating higher-multiplicity
    intersections, III. Codimension 2,” <i>Russian Mathematical Surveys</i>, vol.
    75, no. 6. IOP Publishing, pp. 1156–1158, 2020.
  ista: Avvakumov S, Wagner U, Mabillard I, Skopenkov AB. 2020. Eliminating higher-multiplicity
    intersections, III. Codimension 2. Russian Mathematical Surveys. 75(6), 1156–1158.
  mla: Avvakumov, Sergey, et al. “Eliminating Higher-Multiplicity Intersections, III.
    Codimension 2.” <i>Russian Mathematical Surveys</i>, vol. 75, no. 6, IOP Publishing,
    2020, pp. 1156–58, doi:<a href="https://doi.org/10.1070/RM9943">10.1070/RM9943</a>.
  short: S. Avvakumov, U. Wagner, I. Mabillard, A.B. Skopenkov, Russian Mathematical
    Surveys 75 (2020) 1156–1158.
date_created: 2021-04-04T22:01:22Z
date_published: 2020-12-01T00:00:00Z
date_updated: 2023-08-14T11:43:54Z
day: '01'
department:
- _id: UlWa
doi: 10.1070/RM9943
external_id:
  arxiv:
  - '1511.03501'
  isi:
  - '000625983100001'
intvolume: '        75'
isi: 1
issue: '6'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1511.03501
month: '12'
oa: 1
oa_version: Preprint
page: 1156-1158
publication: Russian Mathematical Surveys
publication_identifier:
  issn:
  - 0036-0279
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
related_material:
  record:
  - id: '8183'
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    status: public
  - id: '10220'
    relation: later_version
    status: public
scopus_import: '1'
status: public
title: Eliminating higher-multiplicity intersections, III. Codimension 2
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 75
year: '2020'
...
---
_id: '7991'
abstract:
- lang: eng
  text: 'We define and study a discrete process that generalizes the convex-layer
    decomposition of a planar point set. Our process, which we call homotopic curve
    shortening (HCS), starts with a closed curve (which might self-intersect) in the
    presence of a set P⊂ ℝ² of point obstacles, and evolves in discrete steps, where
    each step consists of (1) taking shortcuts around the obstacles, and (2) reducing
    the curve to its shortest homotopic equivalent. We find experimentally that, if
    the initial curve is held fixed and P is chosen to be either a very fine regular
    grid or a uniformly random point set, then HCS behaves at the limit like the affine
    curve-shortening flow (ACSF). This connection between HCS and ACSF generalizes
    the link between "grid peeling" and the ACSF observed by Eppstein et al. (2017),
    which applied only to convex curves, and which was studied only for regular grids.
    We prove that HCS satisfies some properties analogous to those of ACSF: HCS is
    invariant under affine transformations, preserves convexity, and does not increase
    the total absolute curvature. Furthermore, the number of self-intersections of
    a curve, or intersections between two curves (appropriately defined), does not
    increase. Finally, if the initial curve is simple, then the number of inflection
    points (appropriately defined) does not increase.'
alternative_title:
- LIPIcs
article_number: 12:1 - 12:15
article_processing_charge: No
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Gabriel
  full_name: Nivasch, Gabriel
  last_name: Nivasch
citation:
  ama: 'Avvakumov S, Nivasch G. Homotopic curve shortening and the affine curve-shortening
    flow. In: <i>36th International Symposium on Computational Geometry</i>. Vol 164.
    Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2020. doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2020.12">10.4230/LIPIcs.SoCG.2020.12</a>'
  apa: 'Avvakumov, S., &#38; Nivasch, G. (2020). Homotopic curve shortening and the
    affine curve-shortening flow. In <i>36th International Symposium on Computational
    Geometry</i> (Vol. 164). Zürich, Switzerland: Schloss Dagstuhl - Leibniz-Zentrum
    für Informatik. <a href="https://doi.org/10.4230/LIPIcs.SoCG.2020.12">https://doi.org/10.4230/LIPIcs.SoCG.2020.12</a>'
  chicago: Avvakumov, Sergey, and Gabriel Nivasch. “Homotopic Curve Shortening and
    the Affine Curve-Shortening Flow.” In <i>36th International Symposium on Computational
    Geometry</i>, Vol. 164. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020.
    <a href="https://doi.org/10.4230/LIPIcs.SoCG.2020.12">https://doi.org/10.4230/LIPIcs.SoCG.2020.12</a>.
  ieee: S. Avvakumov and G. Nivasch, “Homotopic curve shortening and the affine curve-shortening
    flow,” in <i>36th International Symposium on Computational Geometry</i>, Zürich,
    Switzerland, 2020, vol. 164.
  ista: 'Avvakumov S, Nivasch G. 2020. Homotopic curve shortening and the affine curve-shortening
    flow. 36th International Symposium on Computational Geometry. SoCG: Symposium
    on Computational Geometry, LIPIcs, vol. 164, 12:1-12:15.'
  mla: Avvakumov, Sergey, and Gabriel Nivasch. “Homotopic Curve Shortening and the
    Affine Curve-Shortening Flow.” <i>36th International Symposium on Computational
    Geometry</i>, vol. 164, 12:1-12:15, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2020, doi:<a href="https://doi.org/10.4230/LIPIcs.SoCG.2020.12">10.4230/LIPIcs.SoCG.2020.12</a>.
  short: S. Avvakumov, G. Nivasch, in:, 36th International Symposium on Computational
    Geometry, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020.
conference:
  end_date: 2020-06-26
  location: Zürich, Switzerland
  name: 'SoCG: Symposium on Computational Geometry'
  start_date: 2020-06-22
date_created: 2020-06-22T09:14:19Z
date_published: 2020-06-01T00:00:00Z
date_updated: 2021-01-12T08:16:23Z
day: '01'
ddc:
- '510'
department:
- _id: UlWa
doi: 10.4230/LIPIcs.SoCG.2020.12
external_id:
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  - '1909.00263'
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license: https://creativecommons.org/licenses/by/3.0/
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 26611F5C-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P31312
  name: Algorithms for Embeddings and Homotopy Theory
publication: 36th International Symposium on Computational Geometry
publication_identifier:
  isbn:
  - '9783959771436'
  issn:
  - '18688969'
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: Homotopic curve shortening and the affine curve-shortening flow
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/3.0/legalcode
  name: Creative Commons Attribution 3.0 Unported (CC BY 3.0)
  short: CC BY (3.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 164
year: '2020'
...
---
_id: '8156'
abstract:
- lang: eng
  text: 'We present solutions to several problems originating from geometry and discrete
    mathematics: existence of equipartitions, maps without Tverberg multiple points,
    and inscribing quadrilaterals. Equivariant obstruction theory is the natural topological
    approach to these type of questions. However, for the specific problems we consider
    it had yielded only partial or no results. We get our results by complementing
    equivariant obstruction theory with other techniques from topology and geometry.'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
citation:
  ama: Avvakumov S. Topological methods in geometry and discrete mathematics. 2020.
    doi:<a href="https://doi.org/10.15479/AT:ISTA:8156">10.15479/AT:ISTA:8156</a>
  apa: Avvakumov, S. (2020). <i>Topological methods in geometry and discrete mathematics</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:8156">https://doi.org/10.15479/AT:ISTA:8156</a>
  chicago: Avvakumov, Sergey. “Topological Methods in Geometry and Discrete Mathematics.”
    Institute of Science and Technology Austria, 2020. <a href="https://doi.org/10.15479/AT:ISTA:8156">https://doi.org/10.15479/AT:ISTA:8156</a>.
  ieee: S. Avvakumov, “Topological methods in geometry and discrete mathematics,”
    Institute of Science and Technology Austria, 2020.
  ista: Avvakumov S. 2020. Topological methods in geometry and discrete mathematics.
    Institute of Science and Technology Austria.
  mla: Avvakumov, Sergey. <i>Topological Methods in Geometry and Discrete Mathematics</i>.
    Institute of Science and Technology Austria, 2020, doi:<a href="https://doi.org/10.15479/AT:ISTA:8156">10.15479/AT:ISTA:8156</a>.
  short: S. Avvakumov, Topological Methods in Geometry and Discrete Mathematics, Institute
    of Science and Technology Austria, 2020.
date_created: 2020-07-23T09:51:29Z
date_published: 2020-07-24T00:00:00Z
date_updated: 2023-12-18T10:51:01Z
day: '24'
ddc:
- '514'
degree_awarded: PhD
department:
- _id: UlWa
doi: 10.15479/AT:ISTA:8156
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page: '119'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
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  - id: '8185'
    relation: part_of_dissertation
    status: public
  - id: '8184'
    relation: part_of_dissertation
    status: public
  - id: '6355'
    relation: part_of_dissertation
    status: public
  - id: '75'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
title: Topological methods in geometry and discrete mathematics
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '8182'
abstract:
- lang: eng
  text: "Suppose that $n\\neq p^k$ and $n\\neq 2p^k$ for all $k$ and all primes $p$.
    We prove that for any Hausdorff compactum $X$ with a free action of the symmetric
    group $\\mathfrak S_n$ there exists an $\\mathfrak S_n$-equivariant map $X \\to\r\n{\\mathbb
    R}^n$ whose image avoids the diagonal $\\{(x,x\\dots,x)\\in {\\mathbb R}^n|x\\in
    {\\mathbb R}\\}$.\r\n  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\r\ntake 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 $\\mathfrak S_n$-equivariant maps from the boundary\r\n$\\partial\\Delta^{n-1}$
    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."
article_number: '1910.12628'
article_processing_charge: No
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- 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>arXiv</i>.
  apa: Avvakumov, S., &#38; Kudrya, S. (n.d.). Vanishing of all equivariant obstructions
    and the mapping degree. <i>arXiv</i>. arXiv.
  chicago: Avvakumov, Sergey, and Sergey Kudrya. “Vanishing of All Equivariant Obstructions
    and the Mapping Degree.” <i>ArXiv</i>. arXiv, n.d.
  ieee: S. Avvakumov and S. Kudrya, “Vanishing of all equivariant obstructions and
    the mapping degree,” <i>arXiv</i>. arXiv.
  ista: Avvakumov S, Kudrya S. Vanishing of all equivariant obstructions and the mapping
    degree. arXiv, 1910.12628.
  mla: Avvakumov, Sergey, and Sergey Kudrya. “Vanishing of All Equivariant Obstructions
    and the Mapping Degree.” <i>ArXiv</i>, 1910.12628, arXiv.
  short: S. Avvakumov, S. Kudrya, ArXiv (n.d.).
date_created: 2020-07-30T10:45:08Z
date_published: 2019-10-28T00:00:00Z
date_updated: 2023-09-07T13:12:17Z
day: '28'
department:
- _id: UlWa
external_id:
  arxiv:
  - '1910.12628'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1910.12628
month: '10'
oa: 1
oa_version: Preprint
project:
- _id: 26611F5C-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P31312
  name: Algorithms for Embeddings and Homotopy Theory
publication: arXiv
publication_status: submitted
publisher: arXiv
related_material:
  record:
  - id: '11446'
    relation: later_version
    status: public
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Vanishing of all equivariant obstructions and the mapping degree
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2019'
...
---
_id: '8184'
abstract:
- lang: eng
  text: "Denote by ∆N the N-dimensional simplex. A map f : ∆N → Rd is an almost r-embedding
    if fσ1∩. . .∩fσr = ∅ whenever σ1, . . . , σr are pairwise disjoint faces. A counterexample
    to the topological Tverberg conjecture asserts that if r is not a prime power
    and d ≥ 2r + 1, then there is an almost r-embedding ∆(d+1)(r−1) → Rd. This was
    improved by Blagojevi´c–Frick–Ziegler using a simple construction of higher-dimensional
    counterexamples by taking k-fold join power of lower-dimensional ones. We improve
    this further (for d large compared to r): If r is not a prime power and N := (d+
    1)r−r l\r\nd + 2 r + 1 m−2, then there is an almost r-embedding ∆N → Rd. For the
    r-fold van Kampen–Flores conjecture we also produce counterexamples which are
    stronger than previously known. Our proof is based on generalizations of the Mabillard–Wagner
    theorem on construction of almost r-embeddings from equivariant maps, and of the
    Ozaydin theorem on existence of equivariant maps. "
acknowledgement: We would like to thank F. Frick for helpful discussions
article_number: '1908.08731'
article_processing_charge: No
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: R.
  full_name: Karasev, R.
  last_name: Karasev
- first_name: A.
  full_name: Skopenkov, A.
  last_name: Skopenkov
citation:
  ama: Avvakumov S, Karasev R, Skopenkov A. Stronger counterexamples to the topological
    Tverberg conjecture. <i>arXiv</i>.
  apa: Avvakumov, S., Karasev, R., &#38; Skopenkov, A. (n.d.). Stronger counterexamples
    to the topological Tverberg conjecture. <i>arXiv</i>. arXiv.
  chicago: Avvakumov, Sergey, R. Karasev, and A. Skopenkov. “Stronger Counterexamples
    to the Topological Tverberg Conjecture.” <i>ArXiv</i>. arXiv, n.d.
  ieee: S. Avvakumov, R. Karasev, and A. Skopenkov, “Stronger counterexamples to the
    topological Tverberg conjecture,” <i>arXiv</i>. arXiv.
  ista: Avvakumov S, Karasev R, Skopenkov A. Stronger counterexamples to the topological
    Tverberg conjecture. arXiv, 1908.08731.
  mla: Avvakumov, Sergey, et al. “Stronger Counterexamples to the Topological Tverberg
    Conjecture.” <i>ArXiv</i>, 1908.08731, arXiv.
  short: S. Avvakumov, R. Karasev, A. Skopenkov, ArXiv (n.d.).
date_created: 2020-07-30T10:45:34Z
date_published: 2019-08-23T00:00:00Z
date_updated: 2023-09-08T11:20:02Z
day: '23'
department:
- _id: UlWa
external_id:
  arxiv:
  - '1908.08731'
  isi:
  - '000986519600004'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1908.08731
month: '08'
oa: 1
oa_version: Preprint
project:
- _id: 26611F5C-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P31312
  name: Algorithms for Embeddings and Homotopy Theory
publication: arXiv
publication_status: submitted
publisher: arXiv
related_material:
  record:
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Stronger counterexamples to the topological Tverberg conjecture
type: preprint
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2019'
...
---
_id: '8185'
abstract:
- lang: eng
  text: "In this paper we study envy-free division problems. The classical approach
    to some of such problems, used by David Gale, reduces to considering continuous
    maps of a simplex to itself and finding sufficient conditions when this map hits
    the center of the simplex. The mere continuity is not sufficient for such a conclusion,
    the usual assumption (for example, in the Knaster--Kuratowski--Mazurkiewicz and
    the Gale theorem) is a certain boundary condition.\r\n  We follow Erel Segal-Halevi,
    Fr\\'ed\\'eric Meunier, and Shira Zerbib, and replace the boundary condition by
    another assumption, which has the economic meaning of possibility for a player
    to prefer an empty part in the segment\r\npartition problem. We solve the problem
    positively when $n$, the number of players that divide the segment, is a prime
    power, and we provide counterexamples for every $n$ which is not a prime power.
    We also provide counterexamples relevant to a wider class of fair or envy-free
    partition problems when $n$ is odd and not a prime power."
article_number: '1907.11183'
article_processing_charge: No
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Roman
  full_name: Karasev, Roman
  last_name: Karasev
citation:
  ama: Avvakumov S, Karasev R. Envy-free division using mapping degree. <i>arXiv</i>.
    doi:<a href="https://doi.org/10.48550/arXiv.1907.11183">10.48550/arXiv.1907.11183</a>
  apa: Avvakumov, S., &#38; Karasev, R. (n.d.). Envy-free division using mapping degree.
    <i>arXiv</i>. <a href="https://doi.org/10.48550/arXiv.1907.11183">https://doi.org/10.48550/arXiv.1907.11183</a>
  chicago: Avvakumov, Sergey, and Roman Karasev. “Envy-Free Division Using Mapping
    Degree.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/arXiv.1907.11183">https://doi.org/10.48550/arXiv.1907.11183</a>.
  ieee: S. Avvakumov and R. Karasev, “Envy-free division using mapping degree,” <i>arXiv</i>.
    .
  ista: Avvakumov S, Karasev R. Envy-free division using mapping degree. arXiv, 1907.11183.
  mla: Avvakumov, Sergey, and Roman Karasev. “Envy-Free Division Using Mapping Degree.”
    <i>ArXiv</i>, 1907.11183, doi:<a href="https://doi.org/10.48550/arXiv.1907.11183">10.48550/arXiv.1907.11183</a>.
  short: S. Avvakumov, R. Karasev, ArXiv (n.d.).
date_created: 2020-07-30T10:45:51Z
date_published: 2019-07-25T00:00:00Z
date_updated: 2023-09-07T13:12:17Z
day: '25'
department:
- _id: UlWa
doi: 10.48550/arXiv.1907.11183
external_id:
  arxiv:
  - '1907.11183'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1907.11183
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: 26611F5C-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P31312
  name: Algorithms for Embeddings and Homotopy Theory
publication: arXiv
publication_status: submitted
related_material:
  link:
  - relation: later_version
    url: https://doi.org/10.1112/mtk.12059
  record:
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Envy-free division using mapping degree
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2019'
...
---
_id: '6419'
abstract:
- lang: eng
  text: Characterizing the fitness landscape, a representation of fitness for a large
    set of genotypes, is key to understanding how genetic information is interpreted
    to create functional organisms. Here we determined the evolutionarily-relevant
    segment of the fitness landscape of His3, a gene coding for an enzyme in the histidine
    synthesis pathway, focusing on combinations of amino acid states found at orthologous
    sites of extant species. Just 15% of amino acids found in yeast His3 orthologues
    were always neutral while the impact on fitness of the remaining 85% depended
    on the genetic background. Furthermore, at 67% of sites, amino acid replacements
    were under sign epistasis, having both strongly positive and negative effect in
    different genetic backgrounds. 46% of sites were under reciprocal sign epistasis.
    The fitness impact of amino acid replacements was influenced by only a few genetic
    backgrounds but involved interaction of multiple sites, shaping a rugged fitness
    landscape in which many of the shortest paths between highly fit genotypes are
    inaccessible.
article_number: e1008079
article_processing_charge: No
author:
- first_name: Victoria
  full_name: Pokusaeva, Victoria
  id: 3184041C-F248-11E8-B48F-1D18A9856A87
  last_name: Pokusaeva
  orcid: 0000-0001-7660-444X
- first_name: Dinara R.
  full_name: Usmanova, Dinara R.
  last_name: Usmanova
- first_name: Ekaterina V.
  full_name: Putintseva, Ekaterina V.
  last_name: Putintseva
- first_name: Lorena
  full_name: Espinar, Lorena
  last_name: Espinar
- first_name: Karen
  full_name: Sarkisyan, Karen
  id: 39A7BF80-F248-11E8-B48F-1D18A9856A87
  last_name: Sarkisyan
  orcid: 0000-0002-5375-6341
- first_name: Alexander S.
  full_name: Mishin, Alexander S.
  last_name: Mishin
- first_name: Natalya S.
  full_name: Bogatyreva, Natalya S.
  last_name: Bogatyreva
- first_name: Dmitry
  full_name: Ivankov, Dmitry
  id: 49FF1036-F248-11E8-B48F-1D18A9856A87
  last_name: Ivankov
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Inna S.
  full_name: Povolotskaya, Inna S.
  last_name: Povolotskaya
- first_name: Guillaume J.
  full_name: Filion, Guillaume J.
  last_name: Filion
- first_name: Lucas B.
  full_name: Carey, Lucas B.
  last_name: Carey
- first_name: Fyodor
  full_name: Kondrashov, Fyodor
  id: 44FDEF62-F248-11E8-B48F-1D18A9856A87
  last_name: Kondrashov
  orcid: 0000-0001-8243-4694
citation:
  ama: Pokusaeva V, Usmanova DR, Putintseva EV, et al. An experimental assay of the
    interactions of amino acids from orthologous sequences shaping a complex fitness
    landscape. <i>PLoS Genetics</i>. 2019;15(4). doi:<a href="https://doi.org/10.1371/journal.pgen.1008079">10.1371/journal.pgen.1008079</a>
  apa: Pokusaeva, V., Usmanova, D. R., Putintseva, E. V., Espinar, L., Sarkisyan,
    K., Mishin, A. S., … Kondrashov, F. (2019). An experimental assay of the interactions
    of amino acids from orthologous sequences shaping a complex fitness landscape.
    <i>PLoS Genetics</i>. Public Library of Science. <a href="https://doi.org/10.1371/journal.pgen.1008079">https://doi.org/10.1371/journal.pgen.1008079</a>
  chicago: Pokusaeva, Victoria, Dinara R. Usmanova, Ekaterina V. Putintseva, Lorena
    Espinar, Karen Sarkisyan, Alexander S. Mishin, Natalya S. Bogatyreva, et al. “An
    Experimental Assay of the Interactions of Amino Acids from Orthologous Sequences
    Shaping a Complex Fitness Landscape.” <i>PLoS Genetics</i>. Public Library of
    Science, 2019. <a href="https://doi.org/10.1371/journal.pgen.1008079">https://doi.org/10.1371/journal.pgen.1008079</a>.
  ieee: V. Pokusaeva <i>et al.</i>, “An experimental assay of the interactions of
    amino acids from orthologous sequences shaping a complex fitness landscape,” <i>PLoS
    Genetics</i>, vol. 15, no. 4. Public Library of Science, 2019.
  ista: Pokusaeva V, Usmanova DR, Putintseva EV, Espinar L, Sarkisyan K, Mishin AS,
    Bogatyreva NS, Ivankov D, Akopyan A, Avvakumov S, Povolotskaya IS, Filion GJ,
    Carey LB, Kondrashov F. 2019. An experimental assay of the interactions of amino
    acids from orthologous sequences shaping a complex fitness landscape. PLoS Genetics.
    15(4), e1008079.
  mla: Pokusaeva, Victoria, et al. “An Experimental Assay of the Interactions of Amino
    Acids from Orthologous Sequences Shaping a Complex Fitness Landscape.” <i>PLoS
    Genetics</i>, vol. 15, no. 4, e1008079, Public Library of Science, 2019, doi:<a
    href="https://doi.org/10.1371/journal.pgen.1008079">10.1371/journal.pgen.1008079</a>.
  short: V. Pokusaeva, D.R. Usmanova, E.V. Putintseva, L. Espinar, K. Sarkisyan, A.S.
    Mishin, N.S. Bogatyreva, D. Ivankov, A. Akopyan, S. Avvakumov, I.S. Povolotskaya,
    G.J. Filion, L.B. Carey, F. Kondrashov, PLoS Genetics 15 (2019).
date_created: 2019-05-13T07:58:38Z
date_published: 2019-04-10T00:00:00Z
date_updated: 2023-08-25T10:30:37Z
day: '10'
ddc:
- '570'
department:
- _id: FyKo
doi: 10.1371/journal.pgen.1008079
ec_funded: 1
external_id:
  isi:
  - '000466866000029'
file:
- access_level: open_access
  checksum: cf3889c8a8a16053dacf9c3776cbe217
  content_type: application/pdf
  creator: dernst
  date_created: 2019-05-14T08:26:08Z
  date_updated: 2020-07-14T12:47:30Z
  file_id: '6445'
  file_name: 2019_PLOSGenetics_Pokusaeva.pdf
  file_size: 3726017
  relation: main_file
file_date_updated: 2020-07-14T12:47:30Z
has_accepted_license: '1'
intvolume: '        15'
isi: 1
issue: '4'
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
project:
- _id: 2564DBCA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '665385'
  name: International IST Doctoral Program
publication: PLoS Genetics
publication_identifier:
  eissn:
  - '15537404'
publication_status: published
publisher: Public Library of Science
quality_controlled: '1'
related_material:
  record:
  - id: '9789'
    relation: research_data
    status: public
  - id: '9790'
    relation: research_data
    status: public
  - id: '9797'
    relation: research_data
    status: public
scopus_import: '1'
status: public
title: An experimental assay of the interactions of amino acids from orthologous sequences
  shaping a complex fitness landscape
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: 15
year: '2019'
...
---
_id: '9789'
article_processing_charge: No
author:
- first_name: Victoria
  full_name: Pokusaeva, Victoria
  id: 3184041C-F248-11E8-B48F-1D18A9856A87
  last_name: Pokusaeva
  orcid: 0000-0001-7660-444X
- first_name: Dinara R.
  full_name: Usmanova, Dinara R.
  last_name: Usmanova
- first_name: Ekaterina V.
  full_name: Putintseva, Ekaterina V.
  last_name: Putintseva
- first_name: Lorena
  full_name: Espinar, Lorena
  last_name: Espinar
- first_name: Karen
  full_name: Sarkisyan, Karen
  id: 39A7BF80-F248-11E8-B48F-1D18A9856A87
  last_name: Sarkisyan
  orcid: 0000-0002-5375-6341
- first_name: Alexander S.
  full_name: Mishin, Alexander S.
  last_name: Mishin
- first_name: Natalya S.
  full_name: Bogatyreva, Natalya S.
  last_name: Bogatyreva
- first_name: Dmitry
  full_name: Ivankov, Dmitry
  id: 49FF1036-F248-11E8-B48F-1D18A9856A87
  last_name: Ivankov
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Inna S.
  full_name: Povolotskaya, Inna S.
  last_name: Povolotskaya
- first_name: Guillaume J.
  full_name: Filion, Guillaume J.
  last_name: Filion
- first_name: Lucas B.
  full_name: Carey, Lucas B.
  last_name: Carey
- first_name: Fyodor
  full_name: Kondrashov, Fyodor
  id: 44FDEF62-F248-11E8-B48F-1D18A9856A87
  last_name: Kondrashov
  orcid: 0000-0001-8243-4694
citation:
  ama: Pokusaeva V, Usmanova DR, Putintseva EV, et al. Multiple alignment of His3
    orthologues. 2019. doi:<a href="https://doi.org/10.1371/journal.pgen.1008079.s010">10.1371/journal.pgen.1008079.s010</a>
  apa: Pokusaeva, V., Usmanova, D. R., Putintseva, E. V., Espinar, L., Sarkisyan,
    K., Mishin, A. S., … Kondrashov, F. (2019). Multiple alignment of His3 orthologues.
    Public Library of Science. <a href="https://doi.org/10.1371/journal.pgen.1008079.s010">https://doi.org/10.1371/journal.pgen.1008079.s010</a>
  chicago: Pokusaeva, Victoria, Dinara R. Usmanova, Ekaterina V. Putintseva, Lorena
    Espinar, Karen Sarkisyan, Alexander S. Mishin, Natalya S. Bogatyreva, et al. “Multiple
    Alignment of His3 Orthologues.” Public Library of Science, 2019. <a href="https://doi.org/10.1371/journal.pgen.1008079.s010">https://doi.org/10.1371/journal.pgen.1008079.s010</a>.
  ieee: V. Pokusaeva <i>et al.</i>, “Multiple alignment of His3 orthologues.” Public
    Library of Science, 2019.
  ista: Pokusaeva V, Usmanova DR, Putintseva EV, Espinar L, Sarkisyan K, Mishin AS,
    Bogatyreva NS, Ivankov D, Akopyan A, Avvakumov S, Povolotskaya IS, Filion GJ,
    Carey LB, Kondrashov F. 2019. Multiple alignment of His3 orthologues, Public Library
    of Science, <a href="https://doi.org/10.1371/journal.pgen.1008079.s010">10.1371/journal.pgen.1008079.s010</a>.
  mla: Pokusaeva, Victoria, et al. <i>Multiple Alignment of His3 Orthologues</i>.
    Public Library of Science, 2019, doi:<a href="https://doi.org/10.1371/journal.pgen.1008079.s010">10.1371/journal.pgen.1008079.s010</a>.
  short: V. Pokusaeva, D.R. Usmanova, E.V. Putintseva, L. Espinar, K. Sarkisyan, A.S.
    Mishin, N.S. Bogatyreva, D. Ivankov, A. Akopyan, S. Avvakumov, I.S. Povolotskaya,
    G.J. Filion, L.B. Carey, F. Kondrashov, (2019).
date_created: 2021-08-06T08:38:50Z
date_published: 2019-04-10T00:00:00Z
date_updated: 2023-08-25T10:30:36Z
day: '10'
department:
- _id: FyKo
doi: 10.1371/journal.pgen.1008079.s010
month: '04'
oa_version: Published Version
publisher: Public Library of Science
related_material:
  record:
  - id: '6419'
    relation: used_in_publication
    status: public
status: public
title: Multiple alignment of His3 orthologues
type: research_data_reference
user_id: 6785fbc1-c503-11eb-8a32-93094b40e1cf
year: '2019'
...
---
_id: '9790'
article_processing_charge: No
author:
- first_name: Victoria
  full_name: Pokusaeva, Victoria
  id: 3184041C-F248-11E8-B48F-1D18A9856A87
  last_name: Pokusaeva
  orcid: 0000-0001-7660-444X
- first_name: Dinara R.
  full_name: Usmanova, Dinara R.
  last_name: Usmanova
- first_name: Ekaterina V.
  full_name: Putintseva, Ekaterina V.
  last_name: Putintseva
- first_name: Lorena
  full_name: Espinar, Lorena
  last_name: Espinar
- first_name: Karen
  full_name: Sarkisyan, Karen
  id: 39A7BF80-F248-11E8-B48F-1D18A9856A87
  last_name: Sarkisyan
  orcid: 0000-0002-5375-6341
- first_name: Alexander S.
  full_name: Mishin, Alexander S.
  last_name: Mishin
- first_name: Natalya S.
  full_name: Bogatyreva, Natalya S.
  last_name: Bogatyreva
- first_name: Dmitry
  full_name: Ivankov, Dmitry
  id: 49FF1036-F248-11E8-B48F-1D18A9856A87
  last_name: Ivankov
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Inna S.
  full_name: Povolotskaya, Inna S.
  last_name: Povolotskaya
- first_name: Guillaume J.
  full_name: Filion, Guillaume J.
  last_name: Filion
- first_name: Lucas B.
  full_name: Carey, Lucas B.
  last_name: Carey
- first_name: Fyodor
  full_name: Kondrashov, Fyodor
  id: 44FDEF62-F248-11E8-B48F-1D18A9856A87
  last_name: Kondrashov
  orcid: 0000-0001-8243-4694
citation:
  ama: Pokusaeva V, Usmanova DR, Putintseva EV, et al. A statistical summary of segment
    libraries and sequencing results. 2019. doi:<a href="https://doi.org/10.1371/journal.pgen.1008079.s011">10.1371/journal.pgen.1008079.s011</a>
  apa: Pokusaeva, V., Usmanova, D. R., Putintseva, E. V., Espinar, L., Sarkisyan,
    K., Mishin, A. S., … Kondrashov, F. (2019). A statistical summary of segment libraries
    and sequencing results. Public Library of Science. <a href="https://doi.org/10.1371/journal.pgen.1008079.s011">https://doi.org/10.1371/journal.pgen.1008079.s011</a>
  chicago: Pokusaeva, Victoria, Dinara R. Usmanova, Ekaterina V. Putintseva, Lorena
    Espinar, Karen Sarkisyan, Alexander S. Mishin, Natalya S. Bogatyreva, et al. “A
    Statistical Summary of Segment Libraries and Sequencing Results.” Public Library
    of Science, 2019. <a href="https://doi.org/10.1371/journal.pgen.1008079.s011">https://doi.org/10.1371/journal.pgen.1008079.s011</a>.
  ieee: V. Pokusaeva <i>et al.</i>, “A statistical summary of segment libraries and
    sequencing results.” Public Library of Science, 2019.
  ista: Pokusaeva V, Usmanova DR, Putintseva EV, Espinar L, Sarkisyan K, Mishin AS,
    Bogatyreva NS, Ivankov D, Akopyan A, Avvakumov S, Povolotskaya IS, Filion GJ,
    Carey LB, Kondrashov F. 2019. A statistical summary of segment libraries and sequencing
    results, Public Library of Science, <a href="https://doi.org/10.1371/journal.pgen.1008079.s011">10.1371/journal.pgen.1008079.s011</a>.
  mla: Pokusaeva, Victoria, et al. <i>A Statistical Summary of Segment Libraries and
    Sequencing Results</i>. Public Library of Science, 2019, doi:<a href="https://doi.org/10.1371/journal.pgen.1008079.s011">10.1371/journal.pgen.1008079.s011</a>.
  short: V. Pokusaeva, D.R. Usmanova, E.V. Putintseva, L. Espinar, K. Sarkisyan, A.S.
    Mishin, N.S. Bogatyreva, D. Ivankov, A. Akopyan, S. Avvakumov, I.S. Povolotskaya,
    G.J. Filion, L.B. Carey, F. Kondrashov, (2019).
date_created: 2021-08-06T08:50:15Z
date_published: 2019-04-10T00:00:00Z
date_updated: 2023-08-25T10:30:36Z
day: '10'
department:
- _id: FyKo
doi: 10.1371/journal.pgen.1008079.s011
month: '04'
oa_version: Published Version
publisher: Public Library of Science
related_material:
  record:
  - id: '6419'
    relation: used_in_publication
    status: public
status: public
title: A statistical summary of segment libraries and sequencing results
type: research_data_reference
user_id: 6785fbc1-c503-11eb-8a32-93094b40e1cf
year: '2019'
...
---
_id: '75'
abstract:
- lang: eng
  text: We prove that any convex body in the plane can be partitioned into m convex
    parts of equal areas and perimeters for any integer m≥2; this result was previously
    known for prime powers m=pk. We also give a higher-dimensional generalization.
article_number: '1804.03057'
article_processing_charge: No
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: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Roman
  full_name: Karasev, Roman
  last_name: Karasev
citation:
  ama: Akopyan A, Avvakumov S, Karasev R. Convex fair partitions into arbitrary number
    of pieces. 2018. doi:<a href="https://doi.org/10.48550/arXiv.1804.03057">10.48550/arXiv.1804.03057</a>
  apa: Akopyan, A., Avvakumov, S., &#38; Karasev, R. (2018). Convex fair partitions
    into arbitrary number of pieces. arXiv. <a href="https://doi.org/10.48550/arXiv.1804.03057">https://doi.org/10.48550/arXiv.1804.03057</a>
  chicago: Akopyan, Arseniy, Sergey Avvakumov, and Roman Karasev. “Convex Fair Partitions
    into Arbitrary Number of Pieces.” arXiv, 2018. <a href="https://doi.org/10.48550/arXiv.1804.03057">https://doi.org/10.48550/arXiv.1804.03057</a>.
  ieee: A. Akopyan, S. Avvakumov, and R. Karasev, “Convex fair partitions into arbitrary
    number of pieces.” arXiv, 2018.
  ista: Akopyan A, Avvakumov S, Karasev R. 2018. Convex fair partitions into arbitrary
    number of pieces. 1804.03057.
  mla: Akopyan, Arseniy, et al. <i>Convex Fair Partitions into Arbitrary Number of
    Pieces</i>. 1804.03057, arXiv, 2018, doi:<a href="https://doi.org/10.48550/arXiv.1804.03057">10.48550/arXiv.1804.03057</a>.
  short: A. Akopyan, S. Avvakumov, R. Karasev, (2018).
date_created: 2018-12-11T11:44:30Z
date_published: 2018-09-13T00:00:00Z
date_updated: 2023-12-18T10:51:02Z
day: '13'
department:
- _id: HeEd
- _id: JaMa
doi: 10.48550/arXiv.1804.03057
ec_funded: 1
external_id:
  arxiv:
  - '1804.03057'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1804.03057
month: '09'
oa: 1
oa_version: Preprint
project:
- _id: 256E75B8-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '716117'
  name: Optimal Transport and Stochastic Dynamics
publication_status: published
publisher: arXiv
related_material:
  record:
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Convex fair partitions into arbitrary number of pieces
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2018'
...
---
_id: '6355'
abstract:
- lang: eng
  text: We  prove  that  any  cyclic  quadrilateral  can  be  inscribed  in  any  closed  convex
    C1-curve.  The smoothness condition is not required if the quadrilateral is a
    rectangle.
article_number: e7
article_processing_charge: No
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: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
citation:
  ama: Akopyan A, Avvakumov S. Any cyclic quadrilateral can be inscribed in any closed
    convex smooth curve. <i>Forum of Mathematics, Sigma</i>. 2018;6. doi:<a href="https://doi.org/10.1017/fms.2018.7">10.1017/fms.2018.7</a>
  apa: Akopyan, A., &#38; Avvakumov, S. (2018). Any cyclic quadrilateral can be inscribed
    in any closed convex smooth curve. <i>Forum of Mathematics, Sigma</i>. Cambridge
    University Press. <a href="https://doi.org/10.1017/fms.2018.7">https://doi.org/10.1017/fms.2018.7</a>
  chicago: Akopyan, Arseniy, and Sergey Avvakumov. “Any Cyclic Quadrilateral Can Be
    Inscribed in Any Closed Convex Smooth Curve.” <i>Forum of Mathematics, Sigma</i>.
    Cambridge University Press, 2018. <a href="https://doi.org/10.1017/fms.2018.7">https://doi.org/10.1017/fms.2018.7</a>.
  ieee: A. Akopyan and S. Avvakumov, “Any cyclic quadrilateral can be inscribed in
    any closed convex smooth curve,” <i>Forum of Mathematics, Sigma</i>, vol. 6. Cambridge
    University Press, 2018.
  ista: Akopyan A, Avvakumov S. 2018. Any cyclic quadrilateral can be inscribed in
    any closed convex smooth curve. Forum of Mathematics, Sigma. 6, e7.
  mla: Akopyan, Arseniy, and Sergey Avvakumov. “Any Cyclic Quadrilateral Can Be Inscribed
    in Any Closed Convex Smooth Curve.” <i>Forum of Mathematics, Sigma</i>, vol. 6,
    e7, Cambridge University Press, 2018, doi:<a href="https://doi.org/10.1017/fms.2018.7">10.1017/fms.2018.7</a>.
  short: A. Akopyan, S. Avvakumov, Forum of Mathematics, Sigma 6 (2018).
date_created: 2019-04-30T06:09:57Z
date_published: 2018-05-31T00:00:00Z
date_updated: 2023-09-19T14:50:12Z
day: '31'
ddc:
- '510'
department:
- _id: UlWa
- _id: HeEd
- _id: JaMa
doi: 10.1017/fms.2018.7
ec_funded: 1
external_id:
  arxiv:
  - '1712.10205'
  isi:
  - '000433915500001'
file:
- access_level: open_access
  checksum: 5a71b24ba712a3eb2e46165a38fbc30a
  content_type: application/pdf
  creator: dernst
  date_created: 2019-04-30T06:14:58Z
  date_updated: 2020-07-14T12:47:28Z
  file_id: '6356'
  file_name: 2018_ForumMahtematics_Akopyan.pdf
  file_size: 249246
  relation: main_file
file_date_updated: 2020-07-14T12:47:28Z
has_accepted_license: '1'
intvolume: '         6'
isi: 1
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: 256E75B8-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '716117'
  name: Optimal Transport and Stochastic Dynamics
publication: Forum of Mathematics, Sigma
publication_identifier:
  issn:
  - 2050-5094
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
  record:
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Any cyclic quadrilateral can be inscribed in any closed convex smooth curve
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: 6
year: '2018'
...
---
_id: '1522'
abstract:
- lang: eng
  text: 'We classify smooth Brunnian (i.e., unknotted on both components) embeddings
    (S2 × S1) ⊔ S3 → ℝ6. Any Brunnian embedding (S2 × S1) ⊔ S3 → ℝ6 is isotopic to
    an explicitly constructed embedding fk,m,n for some integers k, m, n such that
    m ≡ n (mod 2). Two embeddings fk,m,n and fk′ ,m′,n′ are isotopic if and only if
    k = k′, m ≡ m′ (mod 2k) and n ≡ n′ (mod 2k). We use Haefliger’s classification
    of embeddings S3 ⊔ S3 → ℝ6 in our proof. The relation between the embeddings (S2
    × S1) ⊔ S3 → ℝ6 and S3 ⊔ S3 → ℝ6 is not trivial, however. For example, we show
    that there exist embeddings f: (S2 ×S1) ⊔ S3 → ℝ6 and g, g′ : S3 ⊔ S3 → ℝ6 such
    that the componentwise embedded connected sum f # g is isotopic to f # g′ but
    g is not isotopic to g′.'
acknowledgement: "I thank A. Skopenkov for telling me about the problem and for his
  useful remarks.  I also thank A. Sossinsky,\r\nA. Zhubr, M. Skopenkov, P. Akhmetiev,
  and an anonymous referee for their feedback.  Author was partially\r\nsupported
  by Dobrushin fellowship, 2013, and by RFBR grant 15-01-06302."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Serhii
  full_name: Avvakumov, Serhii
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
citation:
  ama: Avvakumov S. The classification of certain linked 3-manifolds in 6-space. <i>Moscow
    Mathematical Journal</i>. 2016;16(1):1-25. doi:<a href="https://doi.org/10.17323/1609-4514-2016-16-1-1-25">10.17323/1609-4514-2016-16-1-1-25</a>
  apa: Avvakumov, S. (2016). The classification of certain linked 3-manifolds in 6-space.
    <i>Moscow Mathematical Journal</i>. Independent University of Moscow. <a href="https://doi.org/10.17323/1609-4514-2016-16-1-1-25">https://doi.org/10.17323/1609-4514-2016-16-1-1-25</a>
  chicago: Avvakumov, Sergey. “The Classification of Certain Linked 3-Manifolds in
    6-Space.” <i>Moscow Mathematical Journal</i>. Independent University of Moscow,
    2016. <a href="https://doi.org/10.17323/1609-4514-2016-16-1-1-25">https://doi.org/10.17323/1609-4514-2016-16-1-1-25</a>.
  ieee: S. Avvakumov, “The classification of certain linked 3-manifolds in 6-space,”
    <i>Moscow Mathematical Journal</i>, vol. 16, no. 1. Independent University of
    Moscow, pp. 1–25, 2016.
  ista: Avvakumov S. 2016. The classification of certain linked 3-manifolds in 6-space.
    Moscow Mathematical Journal. 16(1), 1–25.
  mla: Avvakumov, Sergey. “The Classification of Certain Linked 3-Manifolds in 6-Space.”
    <i>Moscow Mathematical Journal</i>, vol. 16, no. 1, Independent University of
    Moscow, 2016, pp. 1–25, doi:<a href="https://doi.org/10.17323/1609-4514-2016-16-1-1-25">10.17323/1609-4514-2016-16-1-1-25</a>.
  short: S. Avvakumov, Moscow Mathematical Journal 16 (2016) 1–25.
date_created: 2018-12-11T11:52:30Z
date_published: 2016-01-01T00:00:00Z
date_updated: 2022-02-25T10:15:57Z
day: '01'
department:
- _id: UlWa
doi: 10.17323/1609-4514-2016-16-1-1-25
external_id:
  arxiv:
  - '1408.3918'
intvolume: '        16'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://arxiv.org/abs/1408.3918
month: '01'
oa: 1
oa_version: Preprint
page: 1 - 25
publication: Moscow Mathematical Journal
publication_identifier:
  eissn:
  - 1609-4514
publication_status: published
publisher: Independent University of Moscow
publist_id: '5652'
quality_controlled: '1'
scopus_import: '1'
status: public
title: The classification of certain linked 3-manifolds in 6-space
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 16
year: '2016'
...
---
_id: '8183'
abstract:
- lang: eng
  text: "We study conditions under which a finite simplicial complex $K$ can be mapped
    to $\\mathbb R^d$ without higher-multiplicity intersections. An almost $r$-embedding
    is a map $f: K\\to \\mathbb R^d$ such that the images of any $r$\r\npairwise disjoint
    simplices of $K$ do not have a common point. We show that if $r$ is not a prime
    power and $d\\geq 2r+1$, then there is a counterexample to the topological Tverberg
    conjecture, i.e., there is an almost $r$-embedding of\r\nthe $(d+1)(r-1)$-simplex
    in $\\mathbb R^d$. This improves on previous constructions of counterexamples
    (for $d\\geq 3r$) based on a series of papers by M. \\\"Ozaydin, M. Gromov, P.
    Blagojevi\\'c, F. Frick, G. Ziegler, and the second and fourth present authors.
    The counterexamples are obtained by proving the following algebraic criterion
    in codimension 2: If $r\\ge3$ and if $K$ is a finite $2(r-1)$-complex then there
    exists an almost $r$-embedding $K\\to \\mathbb R^{2r}$ if and only if there exists
    a general position PL map $f:K\\to \\mathbb R^{2r}$ such that the algebraic intersection
    number of the $f$-images of any $r$ pairwise disjoint simplices of $K$ is zero.
    This result can be restated in terms of cohomological obstructions or equivariant
    maps, and extends an analogous codimension 3 criterion by the second and fourth
    authors. As another application we classify ornaments $f:S^3 \\sqcup S^3\\sqcup
    S^3\\to \\mathbb R^5$ up to ornament\r\nconcordance. It follows from work of M.
    Freedman, V. Krushkal and P. Teichner that the analogous criterion for $r=2$ is
    false. We prove a lemma on singular higher-dimensional Borromean rings, yielding
    an elementary proof of the counterexample."
acknowledgement: We would like to thank A. Klyachko, V. Krushkal, S. Melikhov, M.
  Tancer, P. Teichner and anonymous referees for helpful discussions.
article_number: '1511.03501'
article_processing_charge: No
arxiv: 1
author:
- first_name: Sergey
  full_name: Avvakumov, Sergey
  id: 3827DAC8-F248-11E8-B48F-1D18A9856A87
  last_name: Avvakumov
- first_name: Isaac
  full_name: Mabillard, Isaac
  id: 32BF9DAA-F248-11E8-B48F-1D18A9856A87
  last_name: Mabillard
- first_name: A.
  full_name: Skopenkov, A.
  last_name: Skopenkov
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
citation:
  ama: Avvakumov S, Mabillard I, Skopenkov A, Wagner U. Eliminating higher-multiplicity
    intersections, III. Codimension 2. <i>arXiv</i>.
  apa: Avvakumov, S., Mabillard, I., Skopenkov, A., &#38; Wagner, U. (n.d.). Eliminating
    higher-multiplicity intersections, III. Codimension 2. <i>arXiv</i>.
  chicago: Avvakumov, Sergey, Isaac Mabillard, A. Skopenkov, and Uli Wagner. “Eliminating
    Higher-Multiplicity Intersections, III. Codimension 2.” <i>ArXiv</i>, n.d.
  ieee: S. Avvakumov, I. Mabillard, A. Skopenkov, and U. Wagner, “Eliminating higher-multiplicity
    intersections, III. Codimension 2,” <i>arXiv</i>. .
  ista: Avvakumov S, Mabillard I, Skopenkov A, Wagner U. Eliminating higher-multiplicity
    intersections, III. Codimension 2. arXiv, 1511.03501.
  mla: Avvakumov, Sergey, et al. “Eliminating Higher-Multiplicity Intersections, III.
    Codimension 2.” <i>ArXiv</i>, 1511.03501.
  short: S. Avvakumov, I. Mabillard, A. Skopenkov, U. Wagner, ArXiv (n.d.).
date_created: 2020-07-30T10:45:19Z
date_published: 2015-11-15T00:00:00Z
date_updated: 2023-09-07T13:12:17Z
day: '15'
department:
- _id: UlWa
external_id:
  arxiv:
  - '1511.03501'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1511.03501
month: '11'
oa: 1
oa_version: Preprint
publication: arXiv
publication_status: submitted
related_material:
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    relation: later_version
    status: public
  - id: '10220'
    relation: later_version
    status: public
  - id: '8156'
    relation: dissertation_contains
    status: public
status: public
title: Eliminating higher-multiplicity intersections, III. Codimension 2
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2015'
...
