arXiv research

VAEs struggle with surjective multimodal data, especially class labels describing images.

The symplectic representation of mapping classes is not surjective for certain types of mapping classes.

The paper proves neural networks are almost always surjective, impacting model safety.

The paper introduces two-tone colorings for links and shows conditions for surjective dihedral representations.

SSNL improves simulation-based inference for high-dimensional data.

Simplified proof of K3 surface period map surjectivity.

The Hilbert map's image is discussed, showing when it's surjective.

If phi: G-->G' is a surjective homomorphism, we prove that the twisted Alexander polynomial of G is divisible by the twisted Alexander polynomial of G'. As an application, we show non-existence of surjective homomorphism between certain knot groups.

Finite-gap solutions approximate jets of initial data for certain BKM systems.

Proves generic surjectivity of vector bundles via degeneration.

Proves surjectivity of certain smooth maps with non-properness sets.

Period maps surjective for certain gravitational instantons.

The paper studies symmetries in quandles and their relative versions.

Eisenhart's theorem extended to sub-Riemannian metrics on specific Lie algebras.

Study surjectivity of Kirwan map for generalized hyperkähler reduction.

Let $G$ be a compact Lie group, and let $LG$ denote the corresponding loop group. Let $(X,ω)$ be a weakly symplectic Banach manifold. Consider a Hamiltonian action of $LG$ on $(X,ω)$, and assume that the moment map $μ: X \to L\fg^*$ is proper. We consider the function $|μ|^2: X \to \R$, and use a version of Morse theor…

This paper is motivated by a relatively recent work by Joyce in special Lagrangian geometry, but the basic idea of the present paper goes back to an earlier pioneering work of Donaldson in Yang--Mills gauge theory; Donaldson discovered a global structure of a (compactified) moduli space of Yang--Mills instantons, and a…

The paper proves that certain surface mapping class groups do not virtually surject to the integers.

We use Klyachko's methods to prove that the natural map G to G-hat, where G is a torsion-free group and G-hat is obtained by adding a new generator t and a new relator w, is surjective only if w is conjugate to gt or gt^{-1} for some g in G. This solves a special case of the surjectivity problem for group extensions, r…

We prove an analogue of Kirwan surjectivity in the setting of equivariant basic cohomology of K-contact manifolds. If the Reeb vector field induces a free $S^1$-action, the $S^1$-quotient is a symplectic manifold and our result reproduces Kirwan's surjectivity for these symplectic manifolds. We further prove a Tolman-W…

We consider localized deformation for initial data sets of the Einstein field equations with the dominant energy condition. Deformation results with the weak inequality need to be handled delicately. We introduce a modified constraint operator to absorb the first order change of the metric in the dominant energy condit…

Surjectivity of Cannon-Thurston map proven for metric graph bundles.

Study on ALH manifolds with boundary, showing surjectivity of scalar curvature map and mass rigidity.

P. Buser and P. Sarnak showed in 1994 that the maximum, over the moduli space of Riemann surfaces of genus s, of the least conformal length of a nonseparating loop, is logarithmic in s. We present an application of (polynomially) dense Euclidean packings, to estimates for an analogous 2-dimensional conformal systolic i…

Any hyperbolic surface bundle over the circle gives rise to a continuous surjection from the circle to the sphere, by work of Cannon and Thurston. We prove that the order in which this surjection fills out the sphere is dictated by a natural triangulation of the surface bundle (introduced by Agol) when all singularitie…

Let $K$ be a prime knot in $S^3$ and $G(K)=π_1(S^3-K)$ the knot group. We write $K_1 \geq K_2$ if there exists a surjective homomorphism from $G(K_1)$ onto $G(K_2)$. In this paper, we determine this partial order on the set of prime knots with up to 11 crossings. There exist such 801 prime knots and then $640,800$ shou…

This paper uses Morse-theoretic techniques to compute the equivariant Betti numbers of the space of semistable rank two degree zero Higgs bundles over a compact Riemann surface, a method in the spirit of Atiyah and Bott's original approach for semistable holomorphic bundles. This leads to a natural proof that the hyper…

This paper extends Thurston and Tsuboi's work on foliations of $S^3$.

Let G be a compact connected Lie group, and (M,ω) a Hamiltonian G-space with proper moment map μ. We give a surjectivity result which expresses the K-theory of the symplectic quotient M//G in terms of the equivariant K-theory of the original manifold M, under certain technical conditions on μ. This result is a natural …

In this article we introduce conformal Riemannian morphisms. The idea of conformal Riemannian morphism generalizes the notions of an isometric immersion, a Riemannian submersion, an isometry, a Riemannian map and a conformal Riemannian map. We show that every injective conformal Riemannian morphism is an injective conf…

Let $f:M^m\to N^n$ be a smooth map between two differential manifolds with $N$ connected, $f(M)$ closed and $f(M)\neq N$. In this short note, we show that either all the points of $M$ are critical points of $f$ or the dimension the collection of all critical points of $f$ is not less than $n-1$. Some consequences of th…

Maps between classifying spaces for certain groups are studied, with rational cohomology results.

We study a model situation in which direct limit ($\text{colim}$) and inverse limit ($\lim$) do not commute, and offer some computations of their "commutator". The homology of a separable metrizable space $X$ has two well-known approximants: $qH_n(X)$ ("Čech homology") and $pH_n(X)$ ("Čech homology with compact support…

This paper proves a map from flow-spines to contact structures is surjective.

Injective and surjective neural operators for function spaces.

New rigidity theorem on static manifolds with boundary.

New properties established for SO(3) quantum representations, showing density and surjectivity.

Let $PB_n(S_{g,p})$ be the pure braid group of a genus $g>1$ surface with $p$ punctures. In this paper we prove that any surjective homomorphism $PB_n(S_{g,p})\to PB_m(S_{g,p})$ factors through one of the forgetful homomorphisms. We then compute the automorphism group of $PB_n(S_{g,p})$, extending Irmak, Ivanov and McC…

The study generalizes cohomology results for hyperbolic groups.

The paper studies Morse theory for Lie algebra actions on Riemannian foliations.

This paper studies the relationship between fundamental groups of manifolds and their effective regular sets.

We consider a class of topological objects in the 3-sphere $S^3$ which will be called {\it $n$-punctured ball tangles}. Using the Kauffman bracket at $A=e^{πi/4}$, an invariant for a special type of $n$-punctured ball tangles is defined. The invariant $F$ takes values in $PM_{2\times2^n}(\mathbb Z)$, that is the set of…

SurVAE Flows combine VAEs and flows using surjective transformations.

Generalising previous results on classical braid groups by Artin and Lin, we determine the values of m, n $\in$ N for which there exists a surjection between the n-and m-string braid groups of an orientable surface without boundary. This result is essentially based on specific properties of their lower central series, …

A new layer, funnel, reduces dimensionality in flows for better performance.

The paper calculates Alexander polynomials for knots using finite group representations.

Let $(X,J)$ be an almost-complex manifold. In \cite{li-zhang} Li and Zhang introduce $H^{(p,q),(q,p)}_J(X)_{\rr}$ as the cohomology subgroups of the $(p+q)$-th de Rham cohomology group formed by classes represented by real pure-type forms. Given a proper, surjective, pseudo-holomorphic map between two almost-complex ma…

We use controlled topology applied to the action of the infinite dihedral group on a partially compactified plane and deduce two consequences for algebraic K-theory. The first is that the family in the K-theoretic Farrell-Jones conjecture can be reduced to only those virtually cyclic groups which admit a surjection wit…