arXiv research

The paper explores methods to decompose periodic maps into Dehn twists.

Constructs differential models for twisted Spin^c-bordism and its dual, defining a new anomaly map.

Solves generalized twisted rabbit problems for higher degree polynomials.

The paper explores the twisted Rokhlin property in mapping class groups of surfaces.

Study of codimension-1 embeddings in 3-manifolds using twist maps and push maps.

Develops moment map theory for twisted scalar curvature in Kähler geometry.

Calculates Dehn twist actions on conformal blocks for modular categories.

The Burau representation of the braid group can be used to recover the Alexander polynomial of the closure of a braid. We define twisted Burau maps and use them to compute twisted Alexander polynomials.

We give a small generating set for the twist subgroup of the mapping class group of a non-orientable surface by Dehn twists. The difference between the number of the generators and a lower bound of numbers of generators for the twist subgroup by Dehn twists is one. The lower bounds is obtained from an argument of Hiros…

We establish the Thom isomorphism in twisted K-theory for any real vector bundle and develop the push-forward map in twisted K-theory for any differentiable proper map $f: X\to Y$ (not necessarily K-oriented). The push-forward map generalizes the push-forward map in ordinary K-theory for any $K$-oriented differentiable…

We obtain a finite generating set for the level 2 twist subgroup of the mapping class group of a closed non-orientable surface. The generating set consists of crosscap pushing maps along non-separating two-sided simple loops and squares of Dehn twists along non-separating two-sided simple closed curves. We also prove t…

New natural presentation of supergravity c-map using Hodge structures.

We construct the geometric Baum-Connes assembly map for twisted Lie groupoids, that means for Lie groupoids together with a given groupoid equivariant $PU(H)-$principle bundle. The construction is based on the use of geometric deformation groupoids, these objects allow in particular to give a geometric construction of …

Locally maximizing orbits studied in twist maps and billiards.

We consider a twisted version of the Hurewicz map on the complement of a hyperplane arrangement. The purpose of this paper is to prove surjectivity of the twisted Hurewicz map under some genericity conditions. As a corollary, we also prove that a generic section of the complement of a hyperplane arrangement has non-tri…

The authors study in detail new types of varieties with degenerate Gauss maps: varieties with multiple foci and their particular case, the so-called twisted cones. They prove an existence theorem for twisted cones and describe their structure.

Shifts are not type-preserving on surface graphs.

The paper explores mapping class group quotients by Dehn twists and their representations.

New relation found in 4D symplectic mapping class group.

This is a PhD thesis in low-dimensional topology. Its main purpose is to examine so-called tête-à-tête twists. Those were defined by A'Campo and give an easy combinatorial description of certain mapping classes on surfaces with boundary. Whereas the well-known Dehn twists are twists around a simple closed curve, tête-à…

Paper examines Dehn twists on non-orientable surfaces and their limitations.

We give new upper bounds on the stable commutator lengths of Dehn twists in mapping class groups and new lower bounds on the stable commutator lengths of Dehn twists in hyperelliptic mapping class groups. In particular, we show that the stable commutator lengths of Dehn twists about a nonseparating and a separating cur…

Study on realizing subgroup twists in 3-manifolds.

This paper provides an infinite presentation for a subgroup of mapping class groups of non-orientable surfaces.

We show that our earlier work in \cite{LT05} extends to the twisted case, that is, we defined a notion of moment map and reduction in both twisted generalized complex geometry and twisted generalized Kähler geometry.

Study shows Dehn twist coefficients are consistent across different actions on surfaces.

Boundary Dehn twists become trivial after abelianization.

We study subgroups of the mapping class group of the torus generated by powers generated by powers of Dehn twists. We give a criterion to show when a collection of powers Dehn twists generates a free group using the ping pong lemma. We show that the subgroup generated by three uniform powers of Dehn twists can be eithe…

Study spherical twists on K3 surfaces, compute their centers.

Growth rate of Dehn twist lattice points in Teichmüller space is slower than mapping class group lattice points.

We show that on a nonorientable surface of genus at least 7 any power of a Dehn twist is equal to a single commutator in the mapping class group and the same is true, under additional assumptions, for the twist subgroup, and also for the extended mapping class group of an orientable surface of genus at least 3.

We study monodromies of plane curve singularities and pseudo-periodic homeomorphisms of oriented surfaces with boundary, following an original idea of the first author: tête-à-tête graphs and twists. We completely characterize mapping classes that can be represented by tête-à-tête twists, and generalize the notion to b…

The paper generalizes a result on smooth mapping class groups and proves a property of Dehn twists in 4-manifolds.

Consider a fibred compact Kähler manifold X endowed with a relatively ample line bundle, such that each fibre admits a constant scalar curvature Kähler metric and has discrete automorphism group. Assuming the base of the fibration admits a twisted extremal metric where the twisting form is a certain Weil-Petersson type…

Twisted spectral triples are a twisting of the notion of spectral triple aiming at dealing with some type III geometric situations. In the first part of the paper, we give a geometric construction of the index map of a twisted spectral triple in terms of $σ$-connections on finitely generated projective modules. This ma…

We present a formula expressing Earle's twisted 1-cocycle on the mapping class group of a closed oriented surface of genus >=2 relative to a fixed base point, with coefficients in the first homology group of the surface. For this purpose we compare it with Morita's twisted 1-cocycle which is combinatorial. The key is t…

A geometric model for twisted $K$-homology is introduced. It is modeled after the Mathai-Melrose-Singer fractional analytic index theorem in the same way as the Baum-Douglas model of $K$-homology was modeled after the Atiyah-Singer index theorem. A natural transformation from twisted geometric $K$-homology to the new g…

The paper explores the dynamics of composite symplectic Dehn twists with nonuniform hyperbolicity.

Study shows non-spin 4-manifolds where smooth Nielsen realization fails.

Researchers study Prym representations for handlebody groups, focusing on cyclic cases.

Solves infinite family of cubic polynomial problems.

In this paper, we consider generalized moment maps for Hamiltonian actions on $H$-twisted generalized complex manifolds introduced by Lin and Tolman \cite{Lin}. The main purpose of this paper is to show convexity and connectedness properties for generalized moment maps. We study Hamiltonian torus actions on compact $H$…

Boundary Dehn twist on $K3$ surfaces becomes trivial after abelianization.

Study subgroup actions on mapping class groups using Heisenberg representations.

For any unoriented loop on a compact connected oriented surface with one boundary component, the generalized Dehn twist along the loop is defined as an automorphism of the completed group ring of the fundamental group of the surface. If the loop is simple, this is the usual right handed Dehn twist, in particular realiz…

New bounds on specific torsion lengths for periodic mapping classes.

The study examines the rigidity of mapping class groups under large powers of twists.

Model for assembly map of bordism-invariant functors.