English
Related papers

Related papers: Uniform continuity of POVMs

200 papers

We prove that an equivalent condition for a uniform space to be coverable is that the images of the natural projections in the fundamental inverse system are uniformly open in a certain sense. As corollaries we (1) obtain a concrete way to…

General Topology · Mathematics 2007-10-11 Conrad Plaut

A stable-like process is a Feller process $(X_t)_{t\geq 0}$ taking values in $\mathbb{R}^d$ and whose generator behaves, locally, like an $\alpha$-stable L\'evy process, but the index $\alpha$ and all other characteristics may depend on the…

Probability · Mathematics 2020-05-19 V. Knopova , A. Kulik , R. Schilling

We report an optical detector with tunable positive operator-valued measures (POVMs). The device is based on a combination of weak-field homodyne techniques and photon-number-resolving detection. The resulting POVMs can be continuously…

We express notions of K-stability of polarized spherical varieties in terms of combinatorial data, vastly generalizing the case of toric varieties. We then provide a combinatorial sufficient condition of G-uniform K-stability by studying…

Algebraic Geometry · Mathematics 2026-03-25 Thibaut Delcroix

We characterize the extremal points of the convex set of quantum measurements that are covariant under a finite-dimensional projective representation of a compact group, with action of the group on the measurement probability space which is…

Quantum Physics · Physics 2007-05-23 G. Chiribella , G. M. D'Ariano

We discuss the Berezin transform, a Markov operator associated to positive operator valued measures (POVMs), in a number of contexts including the Berezin-Toeplitz quantization, Donaldson's dynamical system on the space of Hermitian…

Mathematical Physics · Physics 2020-04-23 Louis Ioos , Victoria Kaminker , Leonid Polterovich , Dor Shmoish

Let M be a space of homogeneous type and denote by F^\infty_{cont}(M) the space of finite linear combinations of continuous (1,\infty)-atoms. In this note we give a simple function theoretic proof of the equivalence on F^\infty_{cont}(M) of…

Functional Analysis · Mathematics 2010-04-06 G. Mauceri , S. Meda

We consider metrics which are preserved under a $p$-Wasserstein transport map, up to a possible contraction. In the case $p=1$ this corresponds to a metric which is uniformly curved in the sense of coarse Ricci curvature. We investigate the…

Probability · Mathematics 2017-12-08 Florian Völlering

We consider Markov chains that obey the following general non-linear state space model: $\Phi_{k+1} = F(\Phi_k, \alpha(\Phi_k, U_{k+1}))$ where the function $F$ is $C^1$ while $\alpha$ is typically discontinuous and $\{U_k: k \in…

Probability · Mathematics 2019-02-07 Alexandre Chotard , Anne Auger

Every exchangeable Feller process taking values in a suitably nice combinatorial state space can be constructed by a system of iterated random Lipschitz functions. In discrete time, the construction proceeds by iterated application of…

Probability · Mathematics 2016-05-27 Harry Crane , Henry Towsner

We consider particles prepared by the von Neumann-L\"uders projection. For those particles the standard deviation of the momentum is discussed. We show that infinite standard deviations are not exceptions but rather typical. A necessary and…

Quantum Physics · Physics 2010-06-29 Thomas Schürmann , Ingo Hoffmann

Statistical ensemble formalism of Kim, Mandel and Wolf (J. Opt. Soc. Am. A 4, 433 (1987)) offers a realistic model for characterizing the effect of stochastic non-image forming optical media on the state of polarization of transmittedlight.…

Optics · Physics 2007-06-26 Sudha , A. V. Gopala Rao , A. R. Usha Devi , A. K. Rajagopal

It is shown that mean value of any observable with bounded spectrum can be uniquely determined from binary statistics of the measurement performed on {\it single} qubit ancilla coupled to a given system. The observable structure is fully…

Quantum Physics · Physics 2009-11-07 Pawel Horodecki

Quantum coherence is a crucial resource in quantum resource theory. Previous study mainly focused on standard coherence under a complete orthogonal reference basis. The standard coherence has recently been extended to general…

Quantum Physics · Physics 2023-07-18 Yu-Cheng Chen , Jiong Cheng , Wen-Zhao Zhang , Cheng-Jie Zhang

We show that kernel-based quadrature rules for computing integrals can be seen as a special case of random feature expansions for positive definite kernels, for a particular decomposition that always exists for such kernels. We provide a…

Machine Learning · Computer Science 2015-11-10 Francis Bach

By using the decomposition of the decoherence-free subalgebra N(T) in direct integrals of factors, we obtain a structure theorem for every uniformly continuous QMSs. Moreover we prove that, when there exists a faithful normal invariant…

Quantum Physics · Physics 2021-01-14 Emanuela Sasso , Veronica Umanità

In the present work we consider off-diagonal Jacobi matrices with uncertainty in the position of sparse perturbations. We prove (Theorem 3.2) that the sequence of Pr\"ufer angles (\theta_{k}^{\omega})_{k\geq 1} is u.d mod \pi for all \phi…

Spectral Theory · Mathematics 2011-11-08 S. L. Carvalho , D. H. U. Marchetti , W. F. Wreszinski

When modeling directional data, that is, unit-norm multivariate vectors, a first natural question is to ask whether the directions are uniformly distributed or, on the contrary, whether there exist modes of variation significantly different…

Methodology · Statistics 2018-04-04 Eduardo García-Portugués , Thomas Verdebout

We consider generic i.e., forming an everywhere dense massive subset classes of Markov operators in the space $L^2(X,\mu)$ with a finite continuous measure. Since there is a canonical correspondence that associates with each Markov operator…

Functional Analysis · Mathematics 2007-05-23 A. Vershik

Kernels of $\alpha$-permanental processes of the form \[ v(x,y)=u(x,y)+f(y),\qquad x,y\in S, \] in which $u(x,y)$ is symmetric, and $f$ is an excessive function for the Borel right process with potential densities $u(x,y)$, are considered.…

Probability · Mathematics 2018-02-23 Michael B. Marcus , Jay Rosen