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Related papers: Equivalences for weak crossed products

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Recent work has highlighted the importance of crossed products in correctly elucidating the operator algebraic approach to quantum field theories. In the gravitational context, the crossed product simultaneously promotes von Neumann…

High Energy Physics - Theory · Physics 2024-06-28 Marc S. Klinger , Robert G. Leigh

We establish the Subgradient Theorem for monotone correspondences -- a monotone correspondence is equal to the subdifferential of a potential if and only if it is conservative, i.e. its integral along a closed path vanishes irrespective of…

Theoretical Economics · Economics 2023-08-10 Nicholas C. Bedard , Jacob K. Goeree

In this paper we obtain a new parametric solution of the problem of finding two triads of biquadrates with equal sums and equal products.

Number Theory · Mathematics 2017-07-31 Ajai Choudhry

Products in double categories, as found in cartesian double categories, are an elegant concept with numerous applications, yet also have a few puzzling aspects. In this paper, we revisit double-categorical products from an unbiased…

Category Theory · Mathematics 2026-03-26 Evan Patterson

We define weak units in a semi-monoidal 2-category $\CC$ as cancellable pseudo-idempotents: they are pairs $(I,\alpha)$ where $I$ is an object such that tensoring with $I$ from either side constitutes a biequivalence of $\CC$, and $\alpha:…

Category Theory · Mathematics 2014-07-15 André Joyal , Joachim Kock

A subset $S$ of a group $(G,+)$ is $t$-weakly sequenceable if there is an ordering $(y_1, \ldots, y_k)$ of its elements such that the partial sums~$s_0, s_1, \ldots, s_k$, given by $s_0 = 0$ and $s_i = \sum_{j=1}^i y_j$ for $1 \leq i \leq…

Combinatorics · Mathematics 2024-02-15 Simone Costa , Stefano Della Fiore

In this paper, we study bimodules over a von Neumann algebra $M$ in two related contexts. The first is an inclusion $M \subseteq M \rtimes_\alpha G$, where $G$ is a discrete group acting on a factor $M$ by outer automorphisms. The second is…

Operator Algebras · Mathematics 2014-01-16 Jan Cameron , Roger R. Smith

We have recently defined a weak Markovian bisimulation equivalence in an integrated-time setting, which reduces sequences of exponentially timed internal actions to individual exponentially timed internal actions having the same average…

Logic in Computer Science · Computer Science 2012-07-05 Marco Bernardo

The (relevance) weighted likelihood was introduced to formally embrace a variety of statistical procedures that trade bias for precision. Unlike its classical counterpart, the weighted likelihood combines all relevant information while…

Statistics Theory · Mathematics 2007-06-13 Xiaogang Wang , James V. Zidek

We define strict and weak duality involutions on 2-categories, and prove a coherence theorem that every bicategory with a weak duality involution is biequivalent to a 2-category with a strict duality involution. For this purpose we…

Category Theory · Mathematics 2018-01-26 Michael Shulman

We prove that various notions of supersolutions to the porous medium equation are equivalent under suitable conditions. More spesifically, we consider weak supersolutions, very weak supersolutions, and $m$-superporous functions defined via…

Analysis of PDEs · Mathematics 2016-03-14 Pekka Lehtelä , Teemu Lukkari

In this paper we establish mixed weak inequalities of Fefferman-Stein type for Calder\'on-Zygmund operators and their commutators, improving some previous results known in the literature. The main estimates also generalize the classical…

Classical Analysis and ODEs · Mathematics 2025-11-20 Rocío Ayala , Fabio Berra , Gladis Pradolini

In this paper we introduce the crossed product construction for a discrete group action on an operator system. In analogy to the work of E. Katsoulis and C. Ramsey, we describe three canonical crossed products arising from such a dynamical…

Operator Algebras · Mathematics 2019-02-08 Samuel J. Harris , Se-Jin Kim

It is well known that the generalized (or quotient) singular values of a matrix pair $(A, C)$ can be obtained from the generalized eigenvalues of a matrix pencil consisting of two augmented matrices. The downside of this reformulation is…

Numerical Analysis · Mathematics 2019-12-19 Ian N. Zwaan

In various analytical contexts, it is proved that a weak Sobolev inequality implies a doubling property for the underlying measure.

Analysis of PDEs · Mathematics 2014-06-10 Lyudmila Korobenko , Diego Maldonado , Cristian Rios

We obtain necessary and sufficient conditions to characterize the boundedness of the composition of dyadic paraproduct operators.

Classical Analysis and ODEs · Mathematics 2016-10-10 Sandra Pott , Maria Carmen Reguera , Eric T. Sawyer , Brett D. Wick

This paper adresses two issues in dealing with bicategories of fractions. The first is to introduce a set of conditions on a class of arrows in a bicategory which is weaker than the one given in Pronk, Etendues and stacks as bicategories of…

Category Theory · Mathematics 2022-08-08 Dorette Pronk , Laura Scull

We construct the Wightman and Green functions in a large class of models of perturbative QFT in the four-dimensional Minkowski space in the Epstein-Glaser framework. To this end we prove the existence of the weak adiabatic limit,…

Mathematical Physics · Physics 2018-03-05 Paweł Duch

We establish the validity of a strong unique continuation property for weakly coupled elliptic systems, including competitive ones. Our proof exploits the system structure and uses Carleman estimates. We apply this result to obtain some…

Analysis of PDEs · Mathematics 2024-10-29 Mónica Clapp , Víctor Hernández-Santamaría , Alberto Saldaña

The weak equivalence principle is studied in a space with noncommutativity of coordinates and noncommutativity of momenta. We find conditions on the parameters of noncommutativity which give the possibility to recover the equivalence…

General Relativity and Quantum Cosmology · Physics 2017-06-27 Kh. P. Gnatenko , V. M. Tkachuk