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Let C be a separable unital C*-algebra, not isomorphic to the complex numbers, equipped with a faithful tracial state. Let A be a unital direct limit of one dimensional NCCW complexes, also equipped with a faithful tracial state. Suppose…

Operator Algebras · Mathematics 2026-02-12 Ilan Hirshberg , N. Christopher Phillips

We use gauge theoretic and algebraic methods to examine sufficient conditions for smooth points on the moduli space of flat connections on a compact manifold and on the character variety of a finitely generated and presented group. We give…

Differential Geometry · Mathematics 2018-09-13 Nan-Kuo Ho , Graeme Wilkin , Siye Wu

We propose a cut-free cyclic system for Transitive Closure Logic (TCL) based on a form of hypersequents, suitable for automated reasoning via proof search. We show that previously proposed sequent systems are cut-free incomplete for basic…

Logic in Computer Science · Computer Science 2022-05-19 Anupam Das , Marianna Girlando

In this note we show that there exist a $2^\mathfrak{c}$-generated free algebra $\mathcal{S} \subset \mathbb{R}^\mathbb{R}$ of Riemann integrable functions and a free algebra $\mathcal{C} \subset \mathbb{R}^{[0,1]}$ of continuous functions,…

Functional Analysis · Mathematics 2024-02-27 E. D'Aniello , J. Fernández-Sánchez , M. Maiuriello , J. B. Seoane Sepúlveda

Replacing operators with continuous operator-valued functions, we prove time-dependent versions of well-known results on compressions and diagonals of bounded operators. The setting of smooth functions is also addressed. Our results have no…

Functional Analysis · Mathematics 2025-12-18 Vladimir Müller , Yuri Tomilov

We give an exposition of the semantics of the simply-typed lambda-calculus, and its linear and ordered variants, using multi-ary structures. We define universal properties for multicategories, and use these to derive familiar rules for…

Logic in Computer Science · Computer Science 2024-05-06 Philip Saville

In this paper, using a relationship between the Schur multiplier of a group $G$, the fundamental group, and the second homology group of the Eilenberg-MacLane space of $G$, we present new proofs for some famous properties of the Schur…

Algebraic Topology · Mathematics 2010-12-16 Behrooz Mashayekhy , Hanieh Mirebrahimi

Szlach\'anyi's skew monoidal categories are a well-motivated variation of monoidal categories in which the unitors and associator are not required to be natural isomorphisms, but merely natural transformations in a particular direction. We…

Logic in Computer Science · Computer Science 2020-03-12 Tarmo Uustalu , Niccolò Veltri , Noam Zeilberger

Each element of the commutator subgroup of a group can be represented as a product of commutators. The minimal number of factors in such a product is called the commutator length of the element. The commutator length of a group is defined…

Symplectic Geometry · Mathematics 2007-05-23 Michael Entov

The swing-twist decomposition is a standard routine in motion planning for humanoid limbs. In this paper the decomposition formulas are derived and discussed in terms of Clifford algebra. With the decomposition one can express an arbitrary…

Robotics · Computer Science 2015-06-19 Przemysław Dobrowolski

It is shown that, given a lattice H in a totally disconnected, locally compact group G, the contraction subgroups in G and the values of the scale function on G are determined by their restrictions to H. Group theoretic properties intrinsic…

Group Theory · Mathematics 2016-02-16 George A. Willis

In this paper we prove the connectedness of symplectic ball packings in the complement of a spherical Lagrangian, S^2 or RP^2, in symplectic manifolds that are rational or ruled. Via a symplectic cutting construction this is a natural…

Symplectic Geometry · Mathematics 2014-02-20 Matthew Strom Borman , Tian-Jun Li , Weiwei Wu

In this note the smooth (i.e. with open stabilizers) linear and {\sl semilinear} representations of certain permutation groups (such as infinite symmetric group or automorphism group of an infinite-dimensional vector space over a finite…

Representation Theory · Mathematics 2015-08-18 M. Rovinsky

This paper gives necessary and sufficient conditions that the free product with amalgamation of circularly-ordered groups admit a circular ordering extending the given orderings of the factors. Our result follows from establishing a…

Group Theory · Mathematics 2019-12-11 Adam Clay , Tyrone Ghaswala

We provide a general structural criterion implying that a group has infinite $m$-almost palindromic width. In particular, we prove that both HNN extensions and free products exhibit infinite $m$-almost palindromic width, with the unique…

Group Theory · Mathematics 2026-03-02 Krishnendu Gongopadhyay , Shrinit Singh

We show that the space of metrics of positive scalar curvature on any 3-manifold is either empty or contractible. Second, we show that the diffeomorphism group of every 3-dimensional spherical space form deformation retracts to its isometry…

Differential Geometry · Mathematics 2019-09-20 Richard H. Bamler , Bruce Kleiner

Using Isabelle/HOL, we verify the state-of-the-art decision procedure for multi-level syllogistic with singleton (MLSS for short), which is a quantifier-free fragment of set theory. We formalise its syntax and semantics as well as a sound…

Logic in Computer Science · Computer Science 2023-07-04 Lukas Stevens

A characterization of freeness for plane curves in terms of the Hilbert function of the associated Milnor algebra is given as well as many new examples of rational cuspidal curves which are free. Some stronger properties are stated as…

Algebraic Geometry · Mathematics 2019-09-17 Alexandru Dimca , Gabriel Sticlaru

Let ${\mathcal C}= \bigcup_{i=1}^n C_i \subseteq \mathbb{P}^2$ be a collection of smooth rational plane curves. We prove that the addition-deletion operation used in the study of hyperplane arrangements has an extension which works for a…

Commutative Algebra · Mathematics 2012-01-31 Hal Schenck , Stefan O. Tohaneanu

We give an explicit expression for the (finitely) flat remainder after analytic normal form reduction of a family of planar saddles of diffeomorphisms or vector fields. We distinguish between a rational or irrational ratio of the moduli of…

Dynamical Systems · Mathematics 2008-02-27 Patrick Bonckaert , Freek Verstringe