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BIMSA Topology Seminar
BIMSA Topology Seminar
Alexander-Markov correspondence for doodles on closed surfaces
Alexander-Markov correspondence for doodles on closed surfaces
Organizers
Speaker
Komal Negi
Time
Thursday, September 17, 2026 3:00 PM - 4:00 PM
Venue
A3-4-301
Online
Zoom 242 742 6089
(BIMSA)
Abstract
In this talk, I will talk about twisted virtual doodles, defined as stable equivalence classes of immersed circles on closed surfaces that may be non-orientable. These objects admit planar representative diagrams, considered up to a suitable set of Reidemeister-type moves. To develop the associated braid-theoretic framework, we define twisted virtual twin groups as natural extensions of virtual twin groups, and establish Alexander- and Markov- type theorems in this set-up. This shows that twisted virtual doodles unify and extend both classical and virtual doodle theories. We further investigate the structure of the pure twisted virtual twin group, providing a presentation and deriving several structural and combinatorial properties. In particular, we obtain two interesting decompositions of the twisted virtual twin group and its pure subgroup, from which it follows that both groups have trivial center and are residually finite as well as Hopfian. This is a joint work with Prof. Mahender Singh.
Speaker Intro
Komal Negi completed her Ph.D. from the Indian Institute of Technology Ropar in 2025. Her research interests lie in knot theory and its generalizations, particularly virtual knot theory and twisted knot theory. A central focus of her work is the construction and study of invariants for twisted knots. She is currently a Postdoctoral Researcher at Science Knot, WPI-SKCM², Hiroshima University, Japan.