English
Related papers

Related papers: Pure maps are strict monomorphisms

200 papers

Let $\mathsf{Q}$ be a commutative and unital quantale. By a $\mathsf{Q}$-map we mean a left adjoint in the quantaloid of sets and $\mathsf{Q}$-relations, and by a partial $\mathsf{Q}$-map we refer to a Kleisli morphism with respect to the…

Category Theory · Mathematics 2025-05-14 Lili Shen , Xiaoye Tang

Theories of classification distinguish classes with some good structure theorem from those for which none is possible. Some classes (dense linear orders, for instance) are non-classifiable in general, but are classifiable when we consider…

Logic · Mathematics 2007-05-23 Wesley Calvert

We consider harmonic maps into pseudo-Riemannian manifolds. We show the removability of isolated singularities for continuous maps, i.e. that any continuous map from an open subset of R^m into a pseudo-Riemannian manifold which is two times…

Analysis of PDEs · Mathematics 2007-05-23 Frederic Helein

A compact K\"ahler manifold is shown to be simply-connected if its `symmetric cotangent algebra' is trivial. Conjecturally, such a manifold should even be rationally connected. The relative version is also shown: a proper surjective…

Algebraic Geometry · Mathematics 2015-11-06 Yohan Brunebarbe , Frédéric Campana

A topological monoid is isomorphic to an endomorphism monoid of a countable structure if and only if it is separable and has a compatible complete ultrametric such that composition from the left is non-expansive. We also give a topological…

Logic · Mathematics 2018-10-16 Manuel Bodirsky , Friedrich Martin Schneider

We consider infinite graphs and the associated energy forms. We show that a graph is canonically compactifiable (i.e. all functions of finite energy are bounded) if and only if the underlying set is totally bounded with respect to any…

Metric Geometry · Mathematics 2020-09-28 Simon Puchert

An oriented compact closed manifold is called inflexible if the set of mapping degrees ranging over all continuous self-maps is finite. Inflexible manifolds have become of importance in the theory of functorial semi-norms on homology.…

Algebraic Topology · Mathematics 2011-09-06 Manuel Amann

If $\lambda$ is (strongly) inaccessible and $2^\lambda = \lambda^+$, then there is a nowhere trivial automorphism of the Boolean algebra $\mathcal P(\lambda)/[\lambda]^{<\lambda}$.

Logic · Mathematics 2024-11-19 Jakob Kellner , Saharon Shelah

We show, assuming the consistency of one measurable cardinal, that it is consistent for there to be exactly kappa+ many normal measures on the least measurable cardinal kappa. This answers a question of Stewart Baldwin. The methods…

Logic · Mathematics 2007-05-23 Arthur W. Apter , James Cummings , Joel David Hamkins

We completely classify the orientable infinite-type surfaces $S$ such that $\operatorname{PMap}(S)$, the pure mapping class group, has automatic continuity. This classification includes surfaces with noncompact boundary. In the case of…

Geometric Topology · Mathematics 2024-06-17 Ryan Dickmann

Given a closed ideal $I$ in a C*-algebra $A$, we show that $A$ is pure if and only if $I$ and $A/I$ are pure. More generally, we study permanence of comparison and divisibility properties when passing to extensions. As an application we…

Operator Algebras · Mathematics 2025-06-13 Francesc Perera , Hannes Thiel , Eduard Vilalta

Let $X$ be a compact metric space which is locally absolutely retract and let $\phi: C(X)\to C(Y, M_n)$ be a unital homomorphism, where $Y$ is a compact metric space with ${\rm dim}Y\le 2.$ It is proved that there exists a sequence of $n$…

Operator Algebras · Mathematics 2009-09-10 Huaxin Lin

Bilinear maps and their classifying tensor products are well-known in the theory of linear algebra, and their generalization to algebras of commutative monads is a classical result of monad theory. Motivated by constructions needed in…

Category Theory · Mathematics 2022-05-12 Tomáš Jakl , Dan Marsden , Nihil Shah

In this paper, we discuss the associated family of harmonic maps $\mathcal{F}: M \rightarrow G/K$ from a Riemann surface $M$ into inner symmetric spaces of compact or non-compact type which are either algebraic or totally symmetric. These…

Differential Geometry · Mathematics 2024-08-23 Josef F. Dorfmeister , Peng Wang

We consider polynomial maps described by so-called "(multivariate) linearized polynomials". These polynomials are defined using a fixed prime power, say q. Linearized polynomials have no mixed terms. Considering invertible polynomial maps…

Commutative Algebra · Mathematics 2012-10-09 Joost Berson

It is shown that the crossed product of a unital AH-algebra with slow dimension growth by an endomorphism is purely infinite when it is simple, provided the endomorphism does not leave a trace state invariant and maps the unit to a full…

Operator Algebras · Mathematics 2010-11-04 Klaus Thomsen

Yet another proof of the result asserting that a morphism of commutative rings is an effective descent morphism for modules if and only if it is pure is given. Moreover, it is shown that this result cannot be derived from Moerdijk's descent…

Category Theory · Mathematics 2012-06-18 Bachuki Mesablishvili

Let $X$ and $Y$ be compact connected complex manifolds of the same dimension with $b_2(X)= b_2(Y)$. We prove that any surjective holomorphic map of degree one from $X$ to $Y$ is a biholomorphism. A version of this was established by the…

Complex Variables · Mathematics 2016-10-21 Gautam Bharali , Indranil Biswas , Georg Schumacher

An argument is given to associate integrable nonintegrable transition of discrete maps with the transition of Lawvere's fixed point theorem to its own contrapositive. We show that the classical description of nonlinear maps is neither…

Dynamical Systems · Mathematics 2016-02-29 S. Saito , N. Saitoh , T. Hatanaka , Y. Wakimoto , T. Yumibayashi

We prove that holomorphic maps from an open subset of a complex smooth projective curve to a complex smooth projective rationally simply connected variety can be approximated by algebraic maps for the compact-open topology. This theorem can…

Algebraic Geometry · Mathematics 2025-08-22 Olivier Benoist , Olivier Wittenberg