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We prove that any finite collection of polygons of equal area has a common hinged dissection. That is, for any such collection of polygons there exists a chain of polygons hinged at vertices that can be folded in the plane continuously…

Computational Geometry · Computer Science 2008-06-12 Timothy G. Abbott , Zachary Abel , David Charlton , Erik D. Demaine , Martin L. Demaine , Scott D. Kominers

Let X be a complex manifold and c a simple closed curve in X. We address the question: What conditions on c ensure the existence of a 1-dimensional complex subvariety V with boundary c in X. When X = C^n, an answer to this question involves…

Complex Variables · Mathematics 2008-08-21 H. Blaine Lawson , John Wermer

Cauchy horizons are shown to be differentiable at endpoints where only a single null generator leaves the horizon. A Cauchy horizon fails to have any null generator endpoints on a given open subset iff it is differentiable on the open…

General Relativity and Quantum Cosmology · Physics 2015-06-25 John K. Beem , Andrzej Krolak

The (n+1)-sphere contains a simple family of constant mean curvature (CMC) hypersurfaces which are products of lower-dimensional spheres called the generalized Clifford hypersurfaces. This paper demonstrates that new, topologically…

Differential Geometry · Mathematics 2007-05-23 Adrian Butscher , Frank Pacard

We prove that if a separable metrizable $X$ is a union of two disjoint 0-dimensional sets $E$, $F$, $E$ is absolutely $G_{\delta}$ and $F$ is absolutely $F_{\sigma\delta}$ then there is a closed embedding $h$ into the union of countable…

General Topology · Mathematics 2025-03-25 Elżbieta Pol , Roman Pol , Mirosława Reńska

For an integer $m\geq 1$, a combinatorial manifold $\widetilde{M}$ is defined to be a geometrical object $\widetilde{M}$ such that for $\forall p\in\widetilde{M}$, there is a local chart $(U_p,\phi_p)$ enable $\phi_p:U_p\to…

General Mathematics · Mathematics 2009-09-29 Linfan Mao

A celebrated theorem of P.M.Cohn says that for any two division rings (not necessarily finite dimensional) over a field F, their amalgamated product over F is a domain which can be embedded in a division ring. Note that even with the two…

Rings and Algebras · Mathematics 2010-09-08 Louis Rowen , David J Saltman

We characterise the set of fundamental groups for which there exist $n$-manifolds that are $h$-cobordant (hence homotopy equivalent) but not simple homotopy equivalent, when $n$ is sufficiently large. In particular, for $n \ge 12$ even, we…

Geometric Topology · Mathematics 2024-09-06 Csaba Nagy , John Nicholson , Mark Powell

Suppose $E$ is an end of an irreducible, properly convex, real-projective $n$-manifold $M$. If $\pi_1E$ contains a subgroup of finite index isomorphic to ${\mathbb Z}^{n-1}$, and $E\hookrightarrow M$ is $\pi_1$-injective, then $E$ is a…

Geometric Topology · Mathematics 2020-09-15 Daryl Cooper , Stephan Tillmann

A generalized quadrangle is a point-line incidence geometry $\mathcal{Q}$ such that: (i) any two points lie on at most one line, and (ii) given a line $\ell$ and a point $P$ not incident with $\ell$, there is a unique point of $\ell$…

Combinatorics · Mathematics 2015-08-17 John Bamberg , Cai Heng Li , Eric Swartz

In this paper, we show that D-compactness in Generalized \v{S}erstnev spaces implies D-boundedness and as in the classical case, a D-bounded and closed subset of a characteristic Generalized \v{S}erstnev is not D-compact in general.…

General Topology · Mathematics 2007-05-23 M. Alimohammady , R. Saadati

A non RNP Banach space E is constructed such that $E^{*}$ is separable and RNP is equivalent to PCP on the subsets of E.

Functional Analysis · Mathematics 2009-09-25 Spiros A. Argyros , Irene Deliyanni

We develop a family of finite element spaces of differential forms defined on cubical meshes in any number of dimensions. The family contains elements of all polynomial degrees and all form degrees. In two dimensions, these include the…

Numerical Analysis · Mathematics 2018-11-13 Douglas N. Arnold , Gerard Awanou

We demonstrate that a phenomenologically viable four-dimensional grand unified theory with no proton decay can be constructed. This is done in the framework of the minimal non-supersymmetric SU(5) GUT by introducing new representations and…

High Energy Physics - Phenomenology · Physics 2018-11-22 Bartosz Fornal , Benjamin Grinstein

We show that the notion of generalized Lenard chains naturally allows formulation of the theory of multi-separable and superintegrable systems in the context of bi-Hamiltonian geometry. We prove that the existence of generalized Lenard…

Exactly Solvable and Integrable Systems · Physics 2015-06-05 Piergiulio Tempesta , Giorgio Tondo

We extend the Colombeau algebra of generalized functions to arbitrary (infinitely differentiable, paracompact) n-dimensional manifolds M. Embedding of continuous functions and distributions is achieved with the help of a family of n-forms…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Balasin

We initiate the study of the generalized quaternionic manifolds by classifying the generalized quaternionic vector spaces, and by giving two classes of nonclassical examples of such manifolds. Thus, we show that any complex symplectic…

Differential Geometry · Mathematics 2011-11-02 Radu Pantilie

F-theory admits 7-branes with exceptional gauge symmetries, which can be compactified to give phenomenological four-dimensional GUT models. Here we study general supersymmetric compactifications of eight-dimensional Yang-Mills theory. They…

High Energy Physics - Theory · Physics 2009-04-09 Ron Donagi , Martijn Wijnholt

A generalized quadrangle is a point-line incidence geometry such that any two points lie on at most one line and, given a line $\ell$ and a point $P$ not incident with $\ell$, there is a unique point of $\ell$ collinear with $P$. We study…

Combinatorics · Mathematics 2018-12-21 Eric Swartz

For any topological group $G$ the dual object $\hat G$ is defined as the set of equivalence classes of irreducible unitary representations of $G$ equipped with the Fell topology. If $G$ is compact, $\hat G$ is discrete. In an earlier paper…

Representation Theory · Mathematics 2021-08-30 M. Ferrer , S. Hernández , V. Uspenskij