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Suppose A and B are unital C*-algebras and A is separable. Let Rep(A,B) denote the set of all unital *-homomorphisms from A to B with the topology of pointwise convergence. We consider the problem of when the closure of the unitary orbit of…

Operator Algebras · Mathematics 2020-08-11 Don Hadwin , Wenjing Liu

Jayne and Rogers proved that every function from an analytic space into a separable metric space is decomposable into countably many continuous functions with closed domains if and only if the preimage of each $F_\sigma$ set under it is…

Logic · Mathematics 2016-09-06 Takayuki Kihara

We study one parameter deformations of a pair consisting of an analytic singular space $X_0$ and a function $f_0$ on it, in case this defines an isolated singularity. We prove, under general conditions, a bouquet decomposition of the Milnor…

Algebraic Geometry · Mathematics 2007-05-23 Guangfeng Jiang , Mihai Tibar

This paper defines a new pseudometric for binary relations between finite sets that measures consensus among subsets. The main results are (1) a concise restatement of this pseudometric with an intuitively appealing interpretation via a…

Geometric Topology · Mathematics 2021-09-28 Kenneth P. Ewing , Michael Robinson

We establish new and different kinds of proofs of properties that arise due to the orthogonal decomposition of the Hilbert space, including projections, over the unit interval of one dimension. We also see angles between functions,…

Functional Analysis · Mathematics 2015-10-28 Dejenie A. Lakew

In the first section of this paper we prove a theorem for the number of columns of a rectangular area that are identical to the given one. In the next section we apply this theorem to derive several combinatorial identities by counting…

Combinatorics · Mathematics 2007-05-23 Milan Janjic

Let $(f, g)$ be a pair of complex analytic functions on a singular analytic space $X$. We give ``the correct'' definition of the relative polar curve of $(f, g)$, and we give a very formal generalization of L\^e's attaching result, which…

Algebraic Geometry · Mathematics 2007-05-23 David B. Massey

We prove some asymptotic results for the radius and the profile of large random bipartite planar maps. Using a bijection due to Bouttier, Di Francesco and Guitter between rooted bipartite planar maps and certain two-type trees with positive…

Probability · Mathematics 2007-05-23 Mathilde Weill

It is well-known that to every binary relation on a non-void set I there can be assigned its incidence matrix, also in the case when I is infinite. We show that a certain kind of "multiplication" of such incidence matrices corresponds to…

Rings and Algebras · Mathematics 2021-11-12 Ivan Chajda , Helmut Länger

We prove a number of results about countable Borel equivalence relations with forcing constructions and arguments. These results reveal hidden regularity properties of Borel complete sections on certain orbits. As consequences they imply…

Logic · Mathematics 2015-03-27 Su Gao , Steve Jackson , Edward Krohne , Brandon Seward

Alternating bilinear maps with few relations allow to define a combinatorial closure similarly as in [2]. For the $\aleph_0$-categorical case we show that this closure is part of the algebraic closure.

Rings and Algebras · Mathematics 2009-09-25 Andreas Baudisch

A separable space is strongly sequentially separable if, for each countable dense set, every point in the space is a limit of a sequence from the dense set. We consider this and related properties, for the spaces of continous and Borel…

General Topology · Mathematics 2019-11-11 Alexander V. Osipov , Piotr Szewczak , Boaz Tsaban

We establish necessary and sufficient conditions for a polynomial to be divisible by a cyclotomic polynomials and derive new formulas involving Ramanujan sums as an application of our results. Additionally, we provide new insights into the…

Number Theory · Mathematics 2025-08-06 Laura De Carli , Maurizio Laporta

In this paper we state and prove ad hoc "Separation Theorems" of the so-called Smooth Commutative Algebra, the Commutative Algebra of \(\mathcal{C}^{\infty}-\)rings. These results are formally similar to the ones we find in (ordinary)…

Commutative Algebra · Mathematics 2021-10-27 Jean Cerqueira Berni , Hugo Luiz Mariano

Some properties of diagonal binomial coefficients were studied in respect to frequency of their units digits. An approach was formulated that led to use of difference tables to predict if certain units digits can appear in the values of…

Number Theory · Mathematics 2017-05-02 Vladimir L. Gavrikov

Let X be a separable Banach space which admits a separating polynomial; in particular X a separable Hilbert space. Let $f:X \rightarrow R$ be bounded, Lipschitz, and $C^1$ with uniformly continuous derivative. Then for each {\epsilon}>0,…

Functional Analysis · Mathematics 2010-11-23 D. Azagra , R. Fry , L. Keener

We consider the problem of determining the complexity of the uniform homeomorphism relation between separable Banach spaces in the Borel reducibility hierarchy of analytic equivalence relations. We prove that the complete $K_{\sigma}$…

Functional Analysis · Mathematics 2009-04-08 Su Gao , Steve Jackson , Bünyamin Sari

It is shown that a linear separation relations are fundamental objects for integration by quadratures of St\"{a}ckel separable Liouville integrable systems (the so-called St\"{a}ckel systems). These relations are further employed for the…

Mathematical Physics · Physics 2015-05-13 Maciej Blaszak

We study matrix three term relations for orthogonal polynomials in two variables constructed from orthogonal polynomials in one variable. Using the three term recurrence relation for the involved univariate orthogonal polynomials, the…

Classical Analysis and ODEs · Mathematics 2016-03-24 Misael Marriaga , Teresa E. Pérez , Miguel A. Piñar

Denote by $x$ a random infinite path in the graph of Pascal's triangle (left and right turns are selected independently with fixed probabilities) and by $d_n(x)$ the binomial coefficient at the $n$'th level along the path $x$. Then for a…

Dynamical Systems · Mathematics 2007-05-23 Terrence M. Adams , Karl E. Petersen