Results 61 to 70 of about 10,056 (177)

On quantum ergodicity for higher‐dimensional cat maps modulo prime powers

Bulletin of the London Mathematical Society, Volume 58, Issue 3, March 2026.
Abstract A discrete model of quantum ergodicity of linear maps generated by symplectic matrices A∈Sp(2d,Z)$A \in \operatorname{Sp}(2d,{\mathbb {Z}})$ modulo an integer N⩾1$N\geqslant 1$, has been studied for d=1$d=1$ and almost all N$N$ by Kurlberg and Rudnick (2001, Comm. Math. Phys., 222, 201–227).
Subham Bhakta, Igor E. Shparlinski
wiley   +1 more source

Scattering theory for difference equations with operator coefficients

Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.
Abstract We investigate a class of second‐order difference equations featuring operator‐valued coefficients with the aim of approaching problems of stationary scattering theory. We focus on various compact perturbations of the discrete Laplacian given in a Hilbert space of bi‐infinite square‐summable sequences with entries from a fixed Hilbert space ...
David Sher, Luis Silva, Boris Vertman, Monika Winklmeier   +3 more
wiley   +1 more source

Surrogate Quantum Circuit Design for the Lattice Boltzmann Collision Operator

International Journal for Numerical Methods in Engineering, Volume 127, Issue 4, 28 February 2026.
ABSTRACT This study introduces a framework for learning a low‐depth surrogate quantum circuit (SQC) that approximates the nonlinear, dissipative, and hence non‐unitary Bhatnagar–Gross–Krook (BGK) collision operator in the lattice Boltzmann method (LBM) for the D2Q9$$ {D}_2{Q}_9 $$ lattice.
Monica Lăcătuş, Matthias Möller
wiley   +1 more source

AI‐Enhanced Signal Detection and Channel Estimation for Beyond 5G and 6G Wireless Networks

Transactions on Emerging Telecommunications Technologies, Volume 36, Issue 12, December 2025.
This paper introduces deep learning‐based methods for channel estimation and signal detection in ma‐MIMO systems, significantly improving performance. FF‐PCNet enhances channel estimation with 40.2% lower error, and LSTM‐DetNet and FF‐DetNet signal detection methods, which achieve superior signal detection with up to 99.993% SER performance and reduced
Muhammad Yunis Daha, Bibin Babu, Rizwan Qureshi, Muhammad Usman Hadi   +3 more
wiley   +1 more source

Norm bounds for Hadamard products and an arithmetic - geometric mean inequality for unitarily invariant norms

, 1995
An arithmetic-geometric mean inequality for unitarily invariant norms and matrices,2∥A∗XB∥⩽∥AA∗X+XBB∗∥,is an immediate consequence of a basic inequality for singular values of Hadamard ...
Horn, Roger A.
core   +1 more source

On the unitarily invariant norms of the matrices connected to complex number sequences [PDF]

, 2020
In this study, we compute the unitarily invariant norms of the matrices A(z) = (z(i)z(j))(i,j=1)(n), B-z = (z(i) - z(j))(i,j=1)(n) and C-z = (z(i)/z(j))(i,j=1)(n), where z(i)s are ith components of any complex sequence (z(n)).
Bahşi, Mustafa
core  

Vladimirov–Pearson operators on ζ$\zeta$‐regular ultrametric Cantor sets

Mathematische Nachrichten, Volume 298, Issue 12, Page 3779-3790, December 2025.
Abstract A new operator for certain types of ultrametric Cantor sets is constructed using the measure coming from the spectral triple associated with the Cantor set, as well as its zeta function. Under certain mild conditions on that measure, it is shown that it is an integral operator similar to the Vladimirov–Taibleson operator on the p$p$‐adic ...
Patrick Erik Bradley
wiley   +1 more source

Enhanced Young-type inequalities utilizing Kantorovich approach for semidefinite matrices

Open Mathematics
This article introduces new Young-type inequalities, leveraging the Kantorovich constant, by refining the original inequality. In addition, we present a range of norm-based inequalities applicable to positive semidefinite matrices, such as the Hilbert ...
Bani-Ahmad Feras, Rashid Mohammad Hussein Mohammad   +1 more
doaj   +1 more source

An Optimal Preconditioned MINRES Method for Symmetrized Multilevel Block Toeplitz Systems With Applications

Numerical Linear Algebra with Applications, Volume 32, Issue 6, December 2025.
ABSTRACT In this work, we propose a novel preconditioned minimal residual method for a class of real, nonsymmetric multilevel block Toeplitz systems, which generalizes an ideal preconditioner established in [J. Pestana. Preconditioners for symmetrized Toeplitz and multilevel Toeplitz matrices. SIAM Journal on Matrix Analysis and Applications, 40(3):870–
Grigorios Tachyridis, Sean Y. Hon
wiley   +1 more source

Unitarily invariant norms related to factors

, 2007
42 pages, the introduction is rewritten, minor ...
Fang, Junsheng, Hadwin, Don
openaire   +2 more sources