Mallika Roy

I am a postdoctoral fellow at Harish-Chandra Research Institute (HRI), India. Prior to this, I was a Margarita Salas postdoctoral fellow in GTA research group at the University of the Basque Country (UPV), Spain. In UPV I was working with Prof. Montserrat Casals-Ruiz and Prof. Ilya Kazachkov.

I did my PhD as a BGSMath fellow (María de Maeztu) from the Universitat Politècnica de Catalunya under the supervision of Prof. Enric Ventura. After finishing my doctoral studies, I was a visiting researcher (March-June, 2020) in the department of Mathematics of the Universidad del País Vasco UPV/EHU working with Prof. Montserrat Casals-Ruiz. Then I was a visiting researcher (July-December, 2020) in LaBRI at Université Bordeaux I-CNRS working with Prof. Pascal Weil. From February 2021 until June 2022, I was a postdoctoral fellow at Chennai Mathematical Institute (CMI) working with Prof. Priyavrat Deshpande.

Research Interests

My research interest lies in the field of Combinatorial and Geometric Group Theory. Within this area I am interested (mainly but not only) in the study of partially commutative groups (a.k.a right-angled Artin groups), Artin groups, Baumslag-Solitar groups, Bestvina-Brady groups from different perspectives (algebraic, algorithmic, combinatorial and geometric) regarding the following topics:

• Studying the finite generability of the intersection of subgroups.

• Combinatorial computation of finite presentation.

• Lattice of quotients in non-elementary subgroups of Hyperbolic groups and acylindrically hyperbolic groups.

• Dynamics of the automorphisms : their fixed points and computation of stabilizers, closures.

• Pullback construction in the category of graphs of groups.

• Complexities of group theoretic algorithms. 

• Homological invariants of word labelled oriented graph groups, Whitehead asphericity conjecture.

• Twisted conjugacy problem and orbit decidability for Baumslag-Solitar groups.

Publications and Preprints

• Fixed subgroups and computation of auto-fixed closures in free-abelian times free groups, joint work with Enric Ventura ; Journal of Pure and Applied Algebra, Volume 224, Issue 4, April 2020. (journal link) (arXiv).

• Degrees of compression and inertia for free-abelian times free groups, joint work with Enric Ventura ; Journal of Algebra, 568 (2021), 241-272. (journal link)  (arXiv).                                       

• Intersection configurations in free and free times free-abelian groups, joint work with Jordi Delgado and Enric Ventura;  Proceedings of the Royal Society of Edinburgh Section A: Mathematics, Vol. 154 Issue 5 (2024), 1552 - 1582. (journal link) (arXiv).

• On the structure of finitely presented Bestvina-Brady groups, joint work with Priyavrat Deshpande; International Journal of Algebra and Computation, Vol. 34, No. 01, pp. 69-85 (2024). (journal link) (arXiv ).

• The central tree property and algorithmic problems on subgroups of free groups, joint work with Enric Ventura and Pascal Weil; Journal of Group Theory, Vol. 27, Issue 5, (2024) 1059-1089. (journal link) (arxiv).

• Computation of endo-fixed closures in free-abelian times free groups, joint work with Enric Ventura; Forum Mathematicum. (journal link) (arxiv).

• Quotient-saturated groups, joint work with Jordi Delgado and Enric Ventura; Journal of Pure and Applied Algebra. (journal link) (arxiv).

• Presentation of kernels of rational characters of right-angled Artin groups, joint work with Montserrat Casals-Ruiz and Ilya Kazachkov; Bulletin of the London Mathematical Society. (journal link) (arxiv).

• Bogomolov multipliers of word labelled oriented graph groups; under review, (arxiv).

• Pullbacks and intersections in categories of graphs of groups, joint work with Jordi Delgado, Marco Linton, Jone Lopez de Gamiz Zearra and Pascal Weil; under review, (arxiv).

• Twisted conjugacy in BS(n,1), joint work with Oorna Mitra and Enric Ventura; under review, (arxiv).

• The finitely generated intersection property in fundamental groups of graphs of groups, joint work with Jordi Delgado, Marco Linton, Jone Lopez de Gamiz Zearra and Pascal Weil; under review, (arxiv).

• Endo-Twisted Conjugacy and Outer Fixed Points in Solvable Baumslag--Solitar Groups; under review, (arxiv).