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Related papers: 50 Open Problems: Ultraproduct II$_1$ factors

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A selection of open problems in the theory of composites is presented. Particular attention is drawn to the question of whether two-dimensional, two-phase, composites with general geometries have the same set of possible effective tensors…

Analysis of PDEs · Mathematics 2021-06-09 Graeme W. Milton

A theorem is derived which (i) provides a new class of subfactors which may be interpreted as generalized asymptotic subfactors, and which (ii) ensures the existence of two-dimensional local quantum field theories associated with certain…

Operator Algebras · Mathematics 2007-05-23 K. -H. Rehren

We present lower bounds on the sum and product of the distinct prime factors of an odd perfect number, which provide a lower bound on the size of the odd perfect number as a function of the number of its distinct prime factors.

Number Theory · Mathematics 2010-08-09 Anirudh Prabhu

Several characterizations are given for a square matrix that can be written as the product of two positive (semidefinite) projections. Based on one of these characterizations, and the theory of alternating projections, a Matlab program is…

Rings and Algebras · Mathematics 2016-03-23 Chi-Kwong Li , Diane Christine Pelejo , Kuo-Zhong Wang

This article is a snap-shot of a web site, which has been collecting open problems in quantum information for several years, and documenting the progress made on these problems. By posting it we make the complete collection available in one…

Quantum Physics · Physics 2007-05-23 O. Krueger , R. F. Werner

Certain new inequalities for the sums of factorials are presented.

General Mathematics · Mathematics 2008-06-03 Mihaly Bencze , Florentin Smarandache

We prove a Kurosh type theorem for free-product type II_1 factors. In particular, if M = LF_2 \otimes R, then the free-product type II_1 factors M*...*M are all prime and pairwise non-isomorphic. This paper is a continuation of [N. Ozawa,…

Operator Algebras · Mathematics 2011-11-10 Narutaka Ozawa

In this paper, we study the formulae for a product of two product Euler polynomials. From this study, we derive some formulae for the integral of the product of two or more Ruler polynomials.

Number Theory · Mathematics 2012-11-21 Taekyun Kim

We consider a variant of the knapsack problem, where items are available with different possible weights. Using a separate budget for these item improvements, the question is: Which items should be improved to which degree such that the…

Optimization and Control · Mathematics 2016-07-29 Marc Goerigk , Yogish Sabharwal , Anita Schöbel , Sandeep Sen

We give an exact coefficients formula of any infinite product of power series with constant term equal to $1$, by using structures from partitions of integers and permutation groups. This is an universal theorem for various of Binomial-type…

Combinatorics · Mathematics 2024-11-05 Kui-Yo Chen , Zhong-Tang Wu

We introduce and study the family of uniformly super McDuff II$_1$ factors. This family is shown to be closed under elementary equivalence and also coincides with the family of II$_1$ factors with the Brown property introduced in…

Operator Algebras · Mathematics 2023-03-07 Isaac Goldbring , David Jekel , Srivatsav Kunnawalkam Elayavalli , Jennifer Pi

We present some questions and suggestion on the second part of the Hilbert 16th problem

Dynamical Systems · Mathematics 2023-02-13 Ali Taghavi

Since it first emerged in Wijsman's seminal work [29], the Wijsman topology has been intensively studied in the past 50 years. In particular, topological properties of Wijsman hyperspaces, relationships between the Wijsman topology and…

General Topology · Mathematics 2016-09-13 Jiling Cao

We show that indecomposable weak Kac algebras are free over their Cartan subalgebras and prove a duality theorem for their actions. Using this result, for any biconnected weak Kac algebra we construct a minimal action on the hyperfinite…

Quantum Algebra · Mathematics 2007-05-23 D. Nikshych

The extending structures problem for Zinbiel 2-algebras is studied. We introduce the concept of unified products for Zinbiel 2-algebras. Some special cases of unified products such as crossed product and matched pair of Zinbiel 2-algebras…

Rings and Algebras · Mathematics 2022-03-01 Ling Zhang , Tao Zhang

Let Q be any II_1-factor. It is shown that any standard lattice G can be realized as the standard invariant of a free product of (several) rescalings of Q. In particular, if Q has fundamental group equal to the positive reals and if P is…

Operator Algebras · Mathematics 2007-05-23 Ken Dykema

We discuss some open problems in a program of constructing and studying two-dimensional conformal field theories using the representation theory of vertex operator algebras.

Quantum Algebra · Mathematics 2017-02-02 Yi-Zhi Huang

We introduce a n-term quadrature to integrate inner products of n functions, as opposed to a Gaussian quadrature to integrate 2n functions. We will characterize and provide computational tools to construct the inner product quadrature, and…

Numerical Analysis · Mathematics 2012-05-04 Yu Chen

The purpose of this paper is to give an effective construction for some induced structures on spheres or product of spheres of codimension 1, 2 or 3, respectively, in Euclidean space endowed with an almost product structure.

Differential Geometry · Mathematics 2007-05-23 Cristina-Elena Hreţcanu

In this small paper we bring together various open problems on geometric multidimensional continued fractions.

Number Theory · Mathematics 2017-12-06 Oleg Karpenkov