The decoherence-free subalgebra of Gaussian Quantum Markov Semigroups
- URL: http://arxiv.org/abs/2112.13781v2
- Date: Sat, 27 Aug 2022 13:56:38 GMT
- Title: The decoherence-free subalgebra of Gaussian Quantum Markov Semigroups
- Authors: Juli\'an Agredo, Franco Fagnola, Damiano Poletti
- Abstract summary: We show that $mathcalN(mathcalT)$ is a type I von Neumann algebra $Linfty(mathbbRd_c;mathbbC)barotimesmathcalB(Gamma(Gamma(mathbbCd))$ determined, up to unitary equivalence, by two natural numbers $d_c,d_fleq d$.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We demonstrate a method for finding the decoherence-subalgebra
$\mathcal{N}(\mathcal{T})$ of a Gaussian quantum Markov semigroup on the von
Neumann algebra $\mathcal{B}(\Gamma(\mathbb{C}^d))$ of all bounded operator on
the Fock space $\Gamma(\mathbb{C}^d)$ on $\mathbb{C}^d$. We show that
$\mathcal{N}(\mathcal{T})$ is a type I von Neumann algebra
$L^\infty(\mathbb{R}^{d_c};\mathbb{C})\bar{\otimes}\mathcal{B}(\Gamma(\mathbb{C}^{d_f}))$
determined, up to unitary equivalence, by two natural numbers $d_c,d_f\leq d$.
This result is illustrated by some applications and examples.
Related papers
- The Communication Complexity of Approximating Matrix Rank [50.6867896228563]
We show that this problem has randomized communication complexity $Omega(frac1kcdot n2log|mathbbF|)$.
As an application, we obtain an $Omega(frac1kcdot n2log|mathbbF|)$ space lower bound for any streaming algorithm with $k$ passes.
arXiv Detail & Related papers (2024-10-26T06:21:42Z) - Quantum charges of harmonic oscillators [55.2480439325792]
We show that the energy eigenfunctions $psi_n$ with $nge 1$ are complex coordinates on orbifolds $mathbbR2/mathbbZ_n$.
We also discuss "antioscillators" with opposite quantum charges and the same positive energy.
arXiv Detail & Related papers (2024-04-02T09:16:18Z) - Provably learning a multi-head attention layer [55.2904547651831]
Multi-head attention layer is one of the key components of the transformer architecture that sets it apart from traditional feed-forward models.
In this work, we initiate the study of provably learning a multi-head attention layer from random examples.
We prove computational lower bounds showing that in the worst case, exponential dependence on $m$ is unavoidable.
arXiv Detail & Related papers (2024-02-06T15:39:09Z) - A Unified Framework for Uniform Signal Recovery in Nonlinear Generative
Compressed Sensing [68.80803866919123]
Under nonlinear measurements, most prior results are non-uniform, i.e., they hold with high probability for a fixed $mathbfx*$ rather than for all $mathbfx*$ simultaneously.
Our framework accommodates GCS with 1-bit/uniformly quantized observations and single index models as canonical examples.
We also develop a concentration inequality that produces tighter bounds for product processes whose index sets have low metric entropy.
arXiv Detail & Related papers (2023-09-25T17:54:19Z) - Increasing subsequences, matrix loci, and Viennot shadows [0.0]
We show that the quotient $mathbbF[mathbfx_n times n]/I_n$ admits a standard monomial basis.
We also calculate the structure of $mathbbF[mathbfx_n times n]/I_n$ as a graded $mathfrakS_n times mathfrakS_n$-module.
arXiv Detail & Related papers (2023-06-14T19:48:01Z) - Learning a Single Neuron with Adversarial Label Noise via Gradient
Descent [50.659479930171585]
We study a function of the form $mathbfxmapstosigma(mathbfwcdotmathbfx)$ for monotone activations.
The goal of the learner is to output a hypothesis vector $mathbfw$ that $F(mathbbw)=C, epsilon$ with high probability.
arXiv Detail & Related papers (2022-06-17T17:55:43Z) - Topological phases of unitary dynamics: Classification in Clifford category [0.0]
A quantum cellular automaton (QCA) or a causal unitary is by definition an automorphism of local operator algebra.
A Clifford QCA is one that maps any Pauli operator to a finite tensor product of Pauli operators.
arXiv Detail & Related papers (2022-05-18T18:00:38Z) - Markovian Repeated Interaction Quantum Systems [0.0]
We study a class of dynamical semigroups $(mathbbLn)_ninmathbbN$ that emerge, by a Feynman--Kac type formalism, from a random quantum dynamical system.
As a physical application, we consider the case where the $mathcalL_omega$'s are the reduced dynamical maps describing the repeated interactions of a system with thermal probes.
arXiv Detail & Related papers (2022-02-10T20:52:40Z) - Uncertainties in Quantum Measurements: A Quantum Tomography [52.77024349608834]
The observables associated with a quantum system $S$ form a non-commutative algebra $mathcal A_S$.
It is assumed that a density matrix $rho$ can be determined from the expectation values of observables.
Abelian algebras do not have inner automorphisms, so the measurement apparatus can determine mean values of observables.
arXiv Detail & Related papers (2021-12-14T16:29:53Z) - Deep Learning in High Dimension: Neural Network Approximation of
Analytic Functions in $L^2(\mathbb{R}^d,\gamma_d)$ [0.0]
We prove expression rates for analytic functions $f:mathbbRdtomathbbR$ in the norm of $L2(mathbbRd,gamma_d)$.
We consider in particular ReLU and ReLU$k$ activations for integer $kgeq 2$.
As an application, we prove expression rate bounds of deep ReLU-NNs for response surfaces of elliptic PDEs with log-Gaussian random field inputs.
arXiv Detail & Related papers (2021-11-13T09:54:32Z) - Bulk-boundary asymptotic equivalence of two strict deformation
quantizations [0.0]
The existence of a strict deformation quantization of $X_k=S(M_k(mathbbC))$ has been proven by both authors and K. Landsman citeLMV.
A similar result is known for the symplectic manifold $S2subsetmathbbR3$.
arXiv Detail & Related papers (2020-05-09T12:03:18Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.