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We show that any of the new knot invariants obtained from Chern-Simons theory based on an arbitrary non-abelian gauge group do not distinguish isotopically inequivalent mutant knots and links. In an attempt to distinguish these knots and…

High Energy Physics - Theory · Physics 2009-10-28 P. Ramadevi , T. R. Govindarajan , R. K. Kaul

Given a contraction of a variety X to a base Y, we enhance the locus in Y over which the contraction is not an isomorphism with a certain sheaf of noncommutative rings D, under mild assumptions which hold in the case of (1) crepant partial…

Algebraic Geometry · Mathematics 2018-11-28 Will Donovan , Michael Wemyss

An n-tuple (n \geq 2), T = (T_1, \ldots, T_n), of commuting bounded linear operators on a Hilbert space \mathcal{H} is doubly commuting if T_i T_j^* = T_j^* T_i for all $1 \leq i < j \leq n$. If in addition, each T_i \in C_{\cdot 0}, then…

Functional Analysis · Mathematics 2016-07-08 T. Bhattacharyya , E. K. Narayanan , Jaydeb Sarkar

We introduce the non-commutative $f$-divergence functional $\Theta(\widetilde{A},\widetilde{B}):=\int_TB_t^{\frac{1}{2}}f\left(B_t^{-\frac{1}{2}} A_tB_t^{-\frac{1}{2}}\right)B_t^{\frac{1}{2}}d\mu(t)$ for an operator convex function $f$,…

Functional Analysis · Mathematics 2014-11-04 Mohammad Sal Moslehian , Mohsen Kian

We establish a dilation-theoretic characterization of the Choquet order on the space of measures on a compact convex set using ideas from the theory of operator algebras. This yields an extension of Cartier's dilation theorem to the…

Operator Algebras · Mathematics 2021-05-03 Kenneth R. Davidson , Matthew Kennedy

In this paper, we develop a novel framework for quantitative mean ergodic theorems in the noncommutative setting, with a focus on actions of amenable groups and semigroups. We prove square function inequalities for ergodic averages arising…

Operator Algebras · Mathematics 2026-01-06 Guixiang Hong , Wei Liu , Samya Kumar Ray , Bang Xu

We consider the discrete Schr\"odinger operator $H = -\Delta + V$ on $\ell^2(\mathbb{Z}^d)$ with a decaying potential, in arbitrary lattice dimension $d\in\mathbb{N}^*$, where $\Delta$ is the standard discrete Laplacian and $V_n =…

Mathematical Physics · Physics 2026-05-12 David Damanik , Zhiyan Zhao

We present a noncommutative extension of Einstein-Hilbert gravity in the context of twist-deformed space-time, with a $\star$-product associated to a quite general triangular Drinfeld twist. In particular the $\star$-product can be chosen…

High Energy Physics - Theory · Physics 2009-07-22 Paolo Aschieri , Leonardo Castellani

This note contains two remarks about the application of the d-invariant in Heegaard Floer homology and Donaldson's diagonalization theorem to knot theory. The first is the equivalence of two obstructions they give to a 2-bridge knot being…

Geometric Topology · Mathematics 2015-12-29 Joshua Evan Greene

We give again a proof of non-homogeneous T1 theorem. Our proof consists of three main parts: a construction of a random dyadic lattice; an estimate of matrix coefficients of a Calder\'on--Zygmund operator with respect to random Haar basis…

Analysis of PDEs · Mathematics 2013-03-05 Alexander Volberg

A determinant in algebraic $K$-theory is associated to any two almost commuting Fredholm operators. On the other hand, one can calculate a homologically defined invariant known as joint torsion. We answer in the affirmative a conjecture of…

K-Theory and Homology · Mathematics 2014-09-24 Joseph Migler

We consider characterisations of unitary dilations and approximations of irreversible classical dynamical systems on a Hilbert space. In the commutative case, building on the work in [9], one can express well known approximants (e.g. Hille-…

Functional Analysis · Mathematics 2023-07-24 Raj Dahya

We characterize Beurling quotient subspaces for pure doubly commuting isometric representations of product systems. As a consequence, we derive a concrete regular dilation theorem for a pure completely contractive covariant representation…

Operator Algebras · Mathematics 2023-10-17 Azad Rohilla , Harsh Trivedi , Shankar Veerabathiran

We investigate some smoothness properties for a transport-diffusion equation involving a class of non-degerate L{\'e}vy type operators with singular drift. Our main argument is based on a duality method using the molecular decomposition of…

Analysis of PDEs · Mathematics 2016-01-06 Diego Chamorro , Stéphane Menozzi

The problems considered in this paper come as a natural continuation of our program to develop a free analogue of Sz.-Nagy-Foias theory, for row contractions. The paper is structured as follows: Introduction Part I. Unitary invariants for…

Operator Algebras · Mathematics 2009-11-29 Gelu Popescu

We introduce a notion of a noncommutative function defined on a domain of $d$-tuples of bounded operators on an infinite dimensional Hilbert space. Inverse and implicit function theorems in this setting are established. When these…

Functional Analysis · Mathematics 2021-08-25 Mark E. Mancuso

The paper presents a new functional model for completely non-unitary contractions on a Hilbert space. This model is based on the observation that the theory of contractions shares a common geometric basis with the extension theory of…

Functional Analysis · Mathematics 2025-03-19 Wang Yicao

We introduce the notion of joint torsion for several commuting operators satisfying a Fredholm condition. This new secondary invariant takes values in the group of invertibles of a field. It is constructed by comparing determinants…

K-Theory and Homology · Mathematics 2010-11-30 Jens Kaad

For commuting contractions $T_1,\dots ,T_n$ acting on a Hilbert space $\mathcal H$ with $T=\prod_{i=1}^n T_i$, we show that $(T_1, \dots, T_n)$ dilates to commuting isometries $(V_1, \dots , V_n)$ on the minimal isometric dilation space of…

Functional Analysis · Mathematics 2024-01-22 Sourav Pal , Prajakta Sahasrabuddhe

We consider non-self-adjoint Schr\"{o}dinger operators $H_{{\rm c}}=-\Delta+V_{{\rm c}}$ (resp. $H_{{\rm r}}=-\Delta+V_{{\rm r}}$) acting in $L^2(\mathbb R^d)$, $d\ge 1$, with dilation analytic complex (resp. real) potentials. We were able…

Spectral Theory · Mathematics 2020-11-16 Norihiro Someyama