arXiv research

The study finds abundant normal generators for mapping class groups.

The study explores normal generators for mapping class groups and their properties.

Every normal subgroup of Cantor tree's mapping class group is geometric.

New normal subgroups found in mapping class groups.

We provide a simple criterion for an element of the mapping class group of a closed surface to have normal closure equal to the whole mapping class group. We apply this to show that every nontrivial periodic mapping class that is not a hyperelliptic involution is a normal generator for the mapping class group when the …

The study classifies normal subgroups of mapping class groups of surfaces with Cantor subsets.

We prove that if a normal subgroup of the extended mapping class group of a closed surface has an element of sufficiently small support then its automorphism group and abstract commensurator group are both isomorphic to the extended mapping class group. The proof relies on another theorem we prove, which states that ma…

Algorithm counts intersections of normal curves efficiently.

Formal Normal Form created for special CR singularities.

Class Normalization improves zero-shot learning models.

Topological normal generation proved for mapping class groups of certain surfaces.

New descriptions of a subgroup in mapping class groups.

We give explicit examples of degree 3 cohomology classes not Poincare dual to submanifolds, and discuss the realisability of homology classes by submanifolds with Spin-C normal bundles.

Geometrically represents L-homology classes using normal maps.

The system of weak normality equations constitutes a part in the complete system of normality equations. Solutions of each of these two systems of equations are associated with some definite classes of Newtonian dynamical systems in Riemannian manifolds. In this paper for the case of simplest flat Riemannian manifold $…

New inequalities for austere submanifolds established.

The paper studies liftable mapping class groups of cyclic covers of spheres.

Formal normal form created for real-smooth hypersurfaces.

We show that the normal closure of any periodic element of the mapping class group of a non-orientable surface whose order is greater than 2 contains the commutator subgroup, which for $g\geq 7$ is equal to the twist subgroup, and provide necessary and sufficient conditions for the normal closures of involutions to con…

Class of Newtonian dynamical systems admitting normal blow-up of points in Riemannian manifolds is considered. Geometric interpretation for weak normality condition, which arose earlier in the theory of dynamical systems admitting the normal shift of hypersurfaces, is found.

In this paper we construct a large class of new normal forms for Levi-nondegenerate real hypersurfaces in complex spaces. We adopt a general approach illustrating why these normal forms are natural and which role is played by the celebrated Chern-Moser normal form. The latter appears in our class as the one with the "m…

The study examines Lipschitz normally embedded Hölder triangles in 4D space.

Paper defines new stability and metrics for complex spaces.

We prove Chern class equalities for abelian families with a holomorphic normal projective connection.

Calculation of the log-normalizer is a major computational obstacle in applications of log-linear models with large output spaces. The problem of fast normalizer computation has therefore attracted significant attention in the theoretical and applied machine learning literature. In this paper, we analyze a recently pro…

In this paper we show that the normal closure of the mth power of a half-twist has infinite index in the mapping class group of a punctured sphere. Furthermore, in some cases we prove that the quotient of the mapping class group of the punctured sphere by the normal closure of a power of a half-twist contains a free ab…

The paper studies special surfaces in 4D space forms with specific geometric properties.

The paper extends logistic regression for unbounded majority classes and derives asymptotic properties.

We define a generalization of Coxeter graphs and an associated Coxeter system and Coxeter mapping class. These can be used to construct periodic Coxeter mapping classes on surfaces with arbitrarily large genus, preserving lots of symmetries. The periodic mapping classes can in turn be used to construct sequences of pse…

Stochastic normalizing flows improve lattice field theory simulations.

Proves a theorem similar to Moser's using a normalization method.

We solve the local equivalence problem for second order (smooth or analytic) ordinary differential equations. We do so by presenting a {\em complete convergent normal form} for this class of ODEs. The normal form is optimal in the sense that it is defined up to the automorphism group of the model (flat) ODE $y"=0$. For…

We prove that many normal subgroups of the extended mapping class group of a surface with punctures are geometric, that is, that their automorphism groups and abstract commensurator groups are isomorphic to the extended mapping class group. In order to apply our theorem to a normal subgroup we require that the "minimal…

It is constructed a normal form for a class of real-smooth surfaces M\subset\mathbb{C}^{2} defined near a degenerate CR singularity.

Neural collapse occurs in normalized features over a Riemannian manifold.

Proposes a novel model-agnostic training procedure for anomaly detection incorporating known anomalies.

In this paper, we study the class of Finsler metrics, namely (α, β)- metrics, which satisfies the un-normal or normal Ricci flow equation.

Unified framework for shrinkage, thresholding, and regularization in normal mean estimation and linear regression.

The paper studies deformations of Kähler manifolds to normal bundles and restricted volumes of big classes.

In this paper, we study the CR submanifolds of maximal CR dimension with flat normal connection of a complex projective space. We first investigate the position of the umbilical normal vector in the normal bundle, especially for the submanifolds of dimension 3. Then as the application, we prove the non-existence of a c…

New proof shows almost all surface group actions are dense.

Discrete normal surfaces are normal surfaces whose intersection with each tetrahedron of a triangulation has at most one component. They are also natural Poincaré duals to 1-cocycles with $\ZZ/2\ZZ$-coefficients. For a fixed cohomology class in a simplicial poset the average Euler characteristic of the associated discr…

Let $M$ be a hyperbolic fibered 3-manifold. We study properties of sequences $(S_{α_n}, ψ_{α_n})$ of fibers and monodromies for primitive integral classes in the fibered cone of $M$. The main tool is the asymptotic translation length $\ell_{\mathcal{C}} (ψ_{α_n})$ of the pseudo-Anosov monodromy $ψ_{α_n}$ on the curve …

This paper proposes a novel generic one-class feature learning method based on intra-class splitting. In one-class classification, feature learning is challenging, because only samples of one class are available during training. Hence, state-of-the-art methods require reference multi-class datasets to pretrain feature …

In this note we show that many subgroups of mapping class groups of infinite-type surfaces without boundary have trivial centers, including all normal subgroups. Using similar techniques, we show that every nontrivial normal subgroup of a big mapping class group contains a nonabelian free group. In contrast, we show th…

The paper finds formulas for word lengths and conjugacy classes in surface groups.

Residual flows are shown to approximate MMD well.

In this paper we describe a procedure for refining the given triangulation of a 3-manifold that scales the PL-metric according to a given weight function while creating no new normal surfaces. It is known that an incompressible surface $F$ in a triangulated 3-manifold $M$ is isotopic to a normal surface that is of mini…