Nansen Petrosyan

Ph.D. 2006, University of Wisconsin-Madison
Associate Professor
Department of Mathematics
University of Southampton
n dot last name at soton dot ac dot uk

I am the principal investigator of the EPSRC-funded research project Classifying spaces for proper actions and almost-flat manifolds

Curriculum Vitae

B.S. Department of Mathematics, Brigham Young University, 1997-2000

Ph.D. Department of Mathematics, University of Wisconsin-Madison, 2001-2006

Visiting Assistant Professor, Department of Mathematics, Indiana Univesity, 2006-07

Postdoctoral Fellow, Department of Mathematics, KU Leuven, 2007-2013

Visiting Positions: University of British Columbia, Canada (Winter 2005), University of Neuchatel, Switzerland (May 2009),

Max Planck Institute, Bonn, Germany (May 2010, March 2012), University of Gdansk, Poland (April 2013, November 2015)

Research Interests

General Areas
Geometric Group Theory and Topology

Specific Interests
Discrete group actions
Classifying spaces of groups for families of subgroups
Crystallographic groups and their generalisations, Coxeter groups, Bestvina-Brady groups
Flat and almost-flat manifolds
Cohomology of groups and Lie algebras, Bredon cohomology


  • Types of manifolds and Poincaré complexes, (joint with J. F. Davis)
    Survey notes.

  • Publications

    1. Bestvina complex for group actions with a strict fundamental domain, (joint with T. Prytula)

    2. Spin structures of flat manifolds of diagonal type, (joint with R. Lutowski, J. Popko, and A. Szczepanski)

    3. Hierarchically cocompact classifying spaces for mapping class groups of surfaces, (joint with B. E. A. Nucinkis)
      Bulletin of the London Mathematical Society (2018) To appear.

    4. Classification of spin structures on four-dimensional almost-flat manifolds, (joint with R. Lutowski and A. Szczepanski)
      Mathematika 64 (2018), 253-266.

    5. On dimensions of groups with cocompact classifying spaces for proper actions, (joint with Ian Leary)
      Advances in Mathematics 311 (2017), 730 - 747.

    6. Complete Bredon cohomology and its applications to hierarchically defined groups, (joint with B. E. A. Nucinkis)
      Mathematical Proceedings of the Cambridge Philosophical Society 161 (2016), no. 1, 143 - 156.

    7. Spin structures on almost-flat manifolds, (joint with A. Gasior and A. Szczepanski)
      Algebraic & Geometric Topology 16 (2016), no. 2, 783 - 796.

    8. Bredon cohomological dimensions for groups acting on CAT(0)-spaces, (joint with D. Degrijse)
      Groups, Geometry, and Dynamics 9 (2015), no. 4, 1231-1265.

    9. Classifying spaces with virtually cyclic stabilizers for linear groups, (joint with D. Degrijse and R. Koehl)
      Transformation Groups 20 (2015) no. 2, 381 - 394.

    10. Action-induced nested classes of groups and jump cohomology,
      Forum Mathematicum 27 (2015), no. 3, 1591-1612.

    11. Crystallographic actions on contractible algebraic manifolds, (joint with K. Dekimpe)
      Transactions of the American Mathematical Society (2015) 367 (4), 2765-2786.

    12. Geometric dimension of groups for the family of virtually cyclic subgroups, (joint with D. Degrijse)
      Journal of Topology (2014) 7 (3), 697-726.

    13. F-structures and Bredon-Galois cohomology, (joint with D. Degrijse)
      Applied Categorical Structures 21 (2013), 545-586.

    14. Commensurators and classifying spaces with virtually cyclic stabilizers, (joint with D. Degrijse)
      Groups, Geometry, and Dynamics 7 (2013), no. 3, 543-555.

    15. On cohomology of crystallographic groups with cyclic holonomy of split type, (joint with B. Putrycz)
      Journal of Algebra 367 (1) (2012), 237-246

    16. On generators of crystallographic groups and actions on flat orbifolds, (joint with A. Adem, K. Dekimpe, and B. Putrycz)
      Journal of Group Theory 15 (2012), 553-561

    17. Intermediaries in Bredon (co)homology and classifying spaces, (joint with F. Dembegioti and O. Talelli)
      Publicacions Matemàtiques 56 (2) (2012), 393-412

    18. On cohomology of split Lie algebra extensions, (joint with D. Degrijse)
      Journal of Lie Theory 22 (1) (2012), 1-15

    19. Characteristic classes for cohomology of split Hopf algebra extensions, (joint with D. Degrijse)
      Journal of Algebra 332 (2011), 366-385

    20. Fiberwise volume non-increasing diffeomorphisms on product manifolds, (joint with D. Dreesen), (extended version)
      Geometriae Dedicate 149 (2010), 417-424

    21. Homology of Hantzsche-Wendt groups, (joint with K. Dekimpe)
      Contemporary Mathematics AMS 501 (2009), 87-103

    22. Cohomology of split group extensions and characteristic classes,
      Journal of Algebra 321 (2009), 2916-2925

    23. Compatible actions and cohomology of crystallographic groups, (joint with A. Adem, J. Ge, and J. Pan),
      Journal of Algebra 320 (2008), 341-353

    24. Jumps in cohomology and free group actions,
      Journal of Pure and Applied Algebra 210 (2007), 695-703

    25. Jumps in cohomology of groups,
      Mathematics in Higher School 2(1) (2006), 11-15. Ministry of Education and Sciences of Republic of Armenia.

    26. Classification of singular fibres of rational elliptic surfaces in characteristic three, (joint with T. Jarvis, W. Lang, G. Rimmasch, J. Roger, and E. Summers),
      Communications in Algebra 33 (2005), 1-34

    Students and Postdocs

  • Tomasz Prytula EPSRC Postdoctoral Fellow 2017-18

  • Ho Yiu Chung PhD 2019 (expected)
    Thesis subject: Crystallographic groups, their generalisations and associated quotient spaces

  • Ana Lopes Onorio PhD 2018 (expected)
    Thesis subject: Relative ends of groups and Bredon cohomology
    joint with Ian Leary

  • Dieter Degrijse PhD 2013
    Thesis subject: Cohomology of split extensions and classifying spaces for families of subgroups

  • Jeroen Wynen MS 2013
    Thesis subject: The construction of buildings and the correspondence with groups

  • Current Teaching

    Hyperbolic Geometry - MATH 6079 Semester I (University of Southampton, 2018-19)

    Some Slide Talks

    Bredon Finiteness Properties for Groups Acting on CAT(0)-spaces (Durham Symposium, 20 August, 2013)

    Crystallographic Actions on Contractible Algebraic Manifolds (Oostende, Belgium, 30 May, 2011)

    Crystallographic Groups and Their Generalizations (Southampton, UK, 6 May, 2011)

    New Action Induced Nested Classes of Groups and Jump (Co)homology (Copenhagen, Denmark, 27 January, 2010)

    An Evolution of the Topological Spherical Space Form Problem (extended slides, Leuven, Belgium, 5 December, 2008)

    Cohomology of Split Group Extensions and Characteristic Classes (Gdansk, Poland, 12 June, 2008)

    Homology of Hantzsche-Wendt Groups (Kortrijk, Belgium, 29 May, 2008)

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