In this paper we study the homeomorphisms of the disk that are liftable with respect to a simple branched covering. Since any such homeomorphism maps the branch set of the covering onto itself and liftability is invariant up to isotopy fixing the branch set, we are dealing in fact with liftable braids. We prove that th…
In this paper, we propose one index i1(f)−i2(f) which measures how well-behaved a given finitely determined multigerm f:(Kn,S)→(Kp,0) (n≤p) of corank at most one is from the viewpoint of liftable vector fields; and we answer the following problems when the index indicates that the giv…
The paper studies liftable mapping class groups of cyclic covers of spheres.
problem Understanding liftable mapping class groups of cyclic covers of spheres.
method Derived finite generating sets, provided algorithms, determined isomorphism classes, derived presentations, and calculated normalizers and centralizers.
result Presentations and isomorphism classes of liftable mapping class groups for various covers.
In this paper, a systematic method is given to construct all liftable vector fields over an analytic multigerm f:(Kn,S)→(Kp,0) of corank at most one admitting a one-parameter stable unfolding.
Generators for the module of vector fields liftable over corank 1 stable complex analytic maps from an n-manifold to an (n+1)-manifold are found. This is applied to the classification of the singularities occuring in generic one-parameter families of maps between these spaces.
The hyperelliptic mapping class group has been studied in various contexts within topology and algebraic geometry. What makes this study tractable is that there is a surjective map from the hyperelliptic mapping class group to a mapping class group of a punctured sphere. The more general family of superelliptic mapping…
Let Mod(Sg) be the mapping class group of the closed orientable surface of genus g≥1. For k≥2, we consider the standard k-sheeted regular cover pk:Sk(g−1)+1→Sg, and analyze the liftable mapping class group LModpk(Sg) associated with the cover pk. In particular,…
The paper studies which branched covers can be lifted to braided embeddings.
problem Which branched covers lift to braided embeddings?
method Analyzes conditions for liftability using Hansen's criterion and examples in different dimensions.
result Not all branched covers lift to braided embeddings; examples are provided in various dimensions.
Statistical relational models provide compact encodings of probabilistic dependencies in relational domains, but result in highly intractable graphical models. The goal of lifted inference is to carry out probabilistic inference without needing to reason about each individual separately, by instead treating exchangeabl…
The paper studies mapping class groups of cyclic covers and their liftable counterparts.
problem Understanding the structure of liftable mapping class groups for cyclic covers.
method Analyzes the liftable mapping class groups of regular cyclic covers and derives explicit generating sets.
result The family of self-normalizing subgroups {LModpk(Sg)}k≥2 forms an infinite family in Mod(Sg). Proves a minimal generating set for a specific group of mapping classes.
problem Finding a minimal generating set for a specific group of mapping classes.
method Proved the group is generated by four elements, with minimal exceptions.
result Minimal generating set for the balanced superelliptic mapping class group.
This paper derives finite generating sets for liftable mapping class groups of certain branched covers of tori.
problem Tackles the structure of liftable mapping class groups of specific branched covers of tori.
method Uses Reidemeister-Schreier rewriting process and Birman-Hilden theory to derive finite generating sets.
result Derives finite generating sets for LModpk(S1,2) for all k≥2. Develops algorithm for finite generating set of liftable mapping class groups of regular abelian covers.
problem Finding finite generating sets for liftable mapping class groups of regular abelian covers.
method Algorithm based on a result providing generating sets for groups acting on graphs with finite quotients.
result Provides finite generating sets for LModp(Sg) for various regular abelian covers. This paper extends braid lifting to coloured braid groupoids for all simple disc covers.
problem Lifting braids to homeomorphisms on branched covers of the disc.
method Defines a map from a coloured braid groupoid to a mapping class groupoid for all simple covers of the disc.
result Characterizes the lift of every coloured braid, recovering classical lifting on liftable braids.
In this paper we investigate surfaces in CP2 without complex points and characterize the minimal surfaces without complex points and the minimal Lagrangian surfaces by Ruh-Vilms type theorems. We also discuss the liftability of an immersion from a surface to CP2 into S5 in Appendix A.
In this paper, we consider a compact Kahler manifold with extremal Kahler metric and a Mumford stable holomorphic bundle over it. We proved that, if the holomorphic vector field defining the extremal Kahler metric is liftable to the bundle and if the bundle is relatively stable with respect to the action of automorphis…
Finite presentation for a specific group in 3D handlebody topology.
problem Finding a finite presentation for a specific group in 3D handlebody topology.
method Constructed a finite presentation for the liftable Hilden group to derive the presentation for the balanced superelliptic handlebody group.
result A finite presentation was given for the balanced superelliptic handlebody group.
The paper solves conditions for metacyclic actions on surfaces, including upper bounds and subgroup classifications.
problem Conditions for metacyclic actions on surfaces and their properties.
method Derives necessary and sufficient conditions for conjugates of torsion elements to generate finite metacyclic subgroups.
result Complete solution to liftability of periodic mapping classes under finite cyclic covers, including upper bounds and subgroup classifications.
Finite presentations for mapping class groups of surfaces and surfaces with points/boundaries.
problem Finding finite presentations for balanced superelliptic mapping class groups.
method Construct finite presentations for corresponding liftable mapping class groups in a different generating set.
result Finite presentations for balanced superelliptic mapping class groups of various surfaces.
Three elements generate balanced superelliptic mapping class groups.
problem Generating balanced superelliptic mapping class groups.
method Proving groups are generated by three elements through normalizers and liftable mapping class groups.
result Balanced superelliptic mapping class groups are generated by three elements.
We consider finite-sheeted, regular, possibly branched covering spaces of compact surfaces with boundary and the associated liftable and symmetric mapping class groups. In particular, we classify when either of these subgroups coincides with the entire mapping class group of the surface. As a consequence, we construct …
Let M be a 3-manifold. Every knotted (embedded) surface in M×R can be moved via an ambient isotopy in such a way that its projection into M is a generic surface. A surface is generic if every point on it is either a regular, double or triple value - the transversal intersection of 1, 2 or 3 embedded surfa…
The paper develops finite knot theory using ropelength-filtered Reidemeister graphs.
problem Understanding knot types in bounded ropelength sublevel spaces.
method Study thick representatives in bounded ropelength sublevel spaces through lifted Reidemeister graphs.
result Define characteristic Reidemeister patterns and finite recognition length.
The paper describes new types of picture-valued invariants and their applications.
problem Understanding and categorizing picture-valued invariants on diagrams.
method General description and classification of derivations and functorial maps.
result Two new examples of functorial maps are introduced, including the order and lifting maps.
Study of Poisson homeomorphisms and rigidity of coisotropic submanifolds.
problem Rigidity and non-rigidity phenomena in Poisson geometry.
method Study of Poisson homeomorphisms, use of clean intersection points, and analysis of characteristic partitions.
result Poisson homeomorphisms preserve symplectic foliations and coisotropic submanifolds are flexible.
In this paper we study the Haefliger invariant for long embeddings R4k−1↪R6k in terms of the self-intersections of their projections to R6k−1, under the condition that the projection is a generic long immersion R4k−1↬R6k−1. We…
Study lifts periodic mapping classes under alternating group actions on surfaces.
problem Classifying subgroups of mapping class groups isomorphic to alternating groups.
method Derived conditions for periodic mapping classes to lift under alternating group actions.
result For n≥7, no subgroup of Mod(Sg) can have an irreducible periodic mapping class.