The Spectral Gap of a Gaussian Quantum Markovian Generator
- URL: http://arxiv.org/abs/2405.04947v1
- Date: Wed, 8 May 2024 10:38:10 GMT
- Title: The Spectral Gap of a Gaussian Quantum Markovian Generator
- Authors: Franco Fagnola, Damiano Poletti, Emanuela Sasso, Veronica Umanità ,
- Abstract summary: Gaussian quantum Markov semigroups are the natural non-commutative extension of classical Ornstein-Uhlenbeck semigroups.
We explicitly compute the optimal exponential convergence rate, namely the spectral gap of the generator, in non-commutative $L2$ spaces.
We do not assume any symmetry or quantum detailed balance condition with respect to the invariant density.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Gaussian quantum Markov semigroups are the natural non-commutative extension of classical Ornstein-Uhlenbeck semigroups. They arise in open quantum systems of bosons where canonical non-commuting random variables of positions and momenta come into play. If there exits a faithful invariant density we explicitly compute the optimal exponential convergence rate, namely the spectral gap of the generator, in non-commutative $L^2$ spaces determined by the invariant density showing that the exact value is the lowest eigenvalue of a certain matrix determined by the diffusion and drift matrices. The spectral gap turns out to depend on the non-commutative $L^2$ space considered, whether the one determined by the so-called GNS or KMS multiplication by the square root of the invariant density. In the first case, it is strictly positive if and only if there is the maximum number of linearly independent noises. While, we exhibit explicit examples in which it is strictly positive only with KMS multiplication. We do not assume any symmetry or quantum detailed balance condition with respect to the invariant density.
Related papers
- Efficient conversion from fermionic Gaussian states to matrix product states [48.225436651971805]
We propose a highly efficient algorithm that converts fermionic Gaussian states to matrix product states.
It can be formulated for finite-size systems without translation invariance, but becomes particularly appealing when applied to infinite systems.
The potential of our method is demonstrated by numerical calculations in two chiral spin liquids.
arXiv Detail & Related papers (2024-08-02T10:15:26Z) - Quantum Random Walks and Quantum Oscillator in an Infinite-Dimensional Phase Space [45.9982965995401]
We consider quantum random walks in an infinite-dimensional phase space constructed using Weyl representation of the coordinate and momentum operators.
We find conditions for their strong continuity and establish properties of their generators.
arXiv Detail & Related papers (2024-06-15T17:39:32Z) - Theoretical Guarantees for Variational Inference with Fixed-Variance Mixture of Gaussians [27.20127082606962]
Variational inference (VI) is a popular approach in Bayesian inference.
This work aims to contribute to the theoretical study of VI in the non-Gaussian case.
arXiv Detail & Related papers (2024-06-06T12:38:59Z) - Symmetry-restricted quantum circuits are still well-behaved [45.89137831674385]
We show that quantum circuits restricted by a symmetry inherit the properties of the whole special unitary group $SU(2n)$.
It extends prior work on symmetric states to the operators and shows that the operator space follows the same structure as the state space.
arXiv Detail & Related papers (2024-02-26T06:23:39Z) - The $\mathfrak S_k$-circular limit of random tensor flattenings [1.2891210250935143]
We show the convergence toward an operator-valued circular system with amalgamation on permutation group algebras.
As an application we describe the law of large random density matrix of bosonic quantum states.
arXiv Detail & Related papers (2023-07-21T08:59:33Z) - Open fermionic string theory in a non commutative target phase-space [0.0]
We investigate an open fermionic string theory in a non-commutative target phase space.
Modified super-Virasoro algebras are obtained in the Ramond and Neuveu-Schwarz sectors.
arXiv Detail & Related papers (2023-07-13T20:58:41Z) - Learning and Concentration for High Dimensional Linear Gaussians: an
Invariant Subspace Approach [0.0]
We study non-asymptotic bounds on correlation between two time realizations of stable linear systems with isotropic Gaussian noise.
Our analysis provide first interpretable and geometric explanation into intricacies of learning and concentration for random dynamical systems.
arXiv Detail & Related papers (2023-04-04T11:11:26Z) - Unified Fourier-based Kernel and Nonlinearity Design for Equivariant
Networks on Homogeneous Spaces [52.424621227687894]
We introduce a unified framework for group equivariant networks on homogeneous spaces.
We take advantage of the sparsity of Fourier coefficients of the lifted feature fields.
We show that other methods treating features as the Fourier coefficients in the stabilizer subgroup are special cases of our activation.
arXiv Detail & Related papers (2022-06-16T17:59:01Z) - Entanglement criteria for the bosonic and fermionic induced ensembles [1.2891210250935143]
We introduce the bosonic and fermionic ensembles of density matrices and study their entanglement.
In the fermionic case, we show that random bipartite fermionic density matrices have non-positive partial transposition, hence they are typically entangled.
arXiv Detail & Related papers (2021-11-10T11:10:11Z) - Spectral clustering under degree heterogeneity: a case for the random
walk Laplacian [83.79286663107845]
This paper shows that graph spectral embedding using the random walk Laplacian produces vector representations which are completely corrected for node degree.
In the special case of a degree-corrected block model, the embedding concentrates about K distinct points, representing communities.
arXiv Detail & Related papers (2021-05-03T16:36:27Z)
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.