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By taking the need for quantum reference frames into account, it is shown that Hilbert-space factorization is a dissipative process requiring on the order of kT to reduce by one bit an observer's uncertainty in the provenance of a…

Quantum Physics · Physics 2014-02-07 Chris Fields

Let T be a bounded operator on a Hilbert space H, and F = {f_j: j in J} an at most countable set of vectors in H. In this note, we characterize the pairs {T, F} such that {T^n f: f in F, n in I} form a frame of H, for the cases of I = N_0…

Functional Analysis · Mathematics 2023-03-21 Carlos Cabrelli , Ursula Molter , Daniel Suárez

Just as knowing some roots of a polynomial allows one to factor it, a well-known result provides a factorization of any scalar differential operator given a set of linearly independent functions in its kernel. This note provides a…

Rings and Algebras · Mathematics 2015-09-18 Alex Kasman

The density classification (DC) task, a computation which maps global density information to local density, is studied using one-dimensional non-unitary quantum cellular automata (QCAs). Two approaches are considered: one that preserves the…

Quantum Physics · Physics 2025-01-22 Elisabeth Wagner , Federico Dell'Anna , Ramil Nigmatullin , Gavin K. Brennen

The volume operator plays a central role in both the kinematics and dynamics of canonical approaches to quantum gravity which are based on algebras of generalized Wilson loops. We introduce a method for simplifying its spectral analysis,…

General Relativity and Quantum Cosmology · Physics 2009-10-30 R. Loll

We propose a mixedness quantifier based on entropy fluctuations. It provides information about the degree of mixedness either for finite dimensional and infinite dimensional Hilbert spaces. It may be used to determine the reduction of the…

Quantum Physics · Physics 2019-07-18 Jorge A. Anaya-Contreras , Arturo Zúñiga-Segundo , Héctor M. Moya-Cessa

A modeling methodology and matrix formalism is presented that permits analysis of arbitrarily complex interferometric waveguide systems, including polarization and backreflection effects. Considerable improvement results from separation of…

Mathematical Physics · Physics 2015-05-20 Robert P. Dahlgren

Finite frame quantization is a discrete version of the coherent state quantization. In the case of a quantum system with finite-dimensional Hilbert space, the finite frame quantization allows us to associate a linear operator to each…

Quantum Physics · Physics 2022-07-18 Nicolae Cotfas

We propose a simpler derivation of the probability density function of Feller Diffusion using the Fourier Transform and solving the resulting equation via the Method of Characteristics. We also discuss simulation algorithms and confirm key…

Probability · Mathematics 2019-06-28 Ranjiva Munasinghe , Leslie Kanthan , Pathum Kossinna

We will study rigorously the notion of mixed states and their density operators (or matrices.) We will also discuss the quantum-mechanical consequences of possible variations of Planck's constant h. This Review has been written having in…

Quantum Physics · Physics 2019-04-17 Maurice A. de Gosson

The quantum density matrix generalises the classical concept of probability distribution to quantum theory. It gives the complete description of a quantum state as well as the observable quantities that can be extracted from it. Its…

Quantum Physics · Physics 2023-08-31 Apoorva D. Patel

We review some of the significant generalizations and applications of the celebrated Douglas theorem on the equivalence of factorization, range inclusion, and majorization of operators. We then apply it to find a characterization of the…

Functional Analysis · Mathematics 2019-10-09 Mohammad Sal Moslehian , Mohsen Kian , Qingxiang Xu

We recall the notion of a differential operator over a smooth map (in linear and non-linear settings) and consider its versions such as formal $\hbar$-differential operators over a map. We study constructions and examples of such operators,…

Differential Geometry · Mathematics 2020-09-29 Ekaterina Shemyakova , Theodore Voronov

Nuclear density functional theory (DFT) is one of the main theoretical tools used to study the properties of heavy and superheavy elements, or to describe the structure of nuclei far from stability. While on-going efforts seek to better…

Nuclear Theory · Physics 2015-12-23 N. Schunck , J. D. McDonnell , D. Higdon , J. Sarich , S. M. Wild

This paper investigates spectral properties of certain classes of positive operators originated from different matrices appeared in linear complementarity problem. These positive operators play a crucial role in various areas of mathematics…

Functional Analysis · Mathematics 2025-02-25 Rashid A. , P Sam Johnson

We determine the density of eigenvalues of the scattering matrix of the Schrodinger operator with a short range potential in the high energy asymptotic regime. We give an explicit formula for this density in terms of the X-ray transform of…

Spectral Theory · Mathematics 2015-05-30 Daniel Bulger , Alexander Pushnitski

To a generalized tight continuous frame in a Hilbert space $\H$ indexed by a locally compact space $\Si$ endowed with a Radon measure, one associates a coorbit theory converting spaces of functions on $\Si$ in spaces of vectors comparable…

Functional Analysis · Mathematics 2014-06-30 M. Mantoiu , D. Parra

A density function for an algebraic invariant is a measurable function on $\mathbb{R}$ which measures the invariant on an $\mathbb{R}$-scale. This function carries a lot more information related to the invariant without seeking extra data.…

Commutative Algebra · Mathematics 2025-04-01 Suprajo Das , Sudeshna Roy , Vijaylaxmi Trivedi

Using the properties of the local Boltzmann weights of integrable interaction-round-a-face (IRF or face) models we express local operators in terms of generalized transfer matrices. This allows for the derivation of discrete functional…

Statistical Mechanics · Physics 2021-09-15 Holger Frahm , Daniel Westerfeld

We present a method to numerically estimate the densities of a discretely sampled data based on binary space partitioning tree. We start with a root node containing all the particles and then recursively divide each node into two nodes each…

Astrophysics · Physics 2015-06-24 Sanjib Sharma , Matthias Steinmetz
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