Geometric Classification of Biased Quantum Capacity via Harmonic Translation
- URL: http://arxiv.org/abs/2603.22336v1
- Date: Sat, 21 Mar 2026 04:17:42 GMT
- Title: Geometric Classification of Biased Quantum Capacity via Harmonic Translation
- Abstract summary: Under uniform locality, the maximal logical dimension under t-local phase errors equals Aq(n,2t+1)>Bq(n,2t+1)<n>For structured phase noise, exact correction is equivalent to independence in an additive Cayley graph.<n>For mixed Pauli noise, simultaneous protection in conjugate domains incurs an intrinsic rate penalty R = 1-(gamma_X+gamma_Z)/2.
- Score: 0.20524609401792393
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We establish an exact noise-model-derived characterization of quantum error correction under diagonal local phase noise. Under uniform locality, the maximal logical dimension under t-local phase errors equals Aq(n,2t+1), the classical q-ary packing function. Because no affine or stabilizer structure is imposed, nonlinear spectral supports achieve this bound and strictly exceed all affine constructions whenever Aq(n,2t+1)>Bq(n,2t+1). This follows from a harmonic translation principle: diagonal phase operators act as rigid translations in the Fourier domain, reducing the Knill-Laflamme conditions exactly to an additive non-collision constraint (S-S) cap Et={0}. For structured phase noise, exact correction is equivalent to independence in an additive Cayley graph, connecting biased quantum capacity to classical zero-error theory and the Lovasz theta function. Under mixed Pauli noise, simultaneous protection in conjugate domains incurs an intrinsic rate penalty R <= 1-(gamma_X+gamma_Z)/2, exposing a discrete harmonic uncertainty principle. In contrast with stabilizer- or graph-based frameworks, this classical correspondence is derived directly from the phase-noise model itself rather than from an auxiliary algebraic construction.
Related papers
- Orientation-dependent Pauli noise in one-dimensional discrete-time quantum walks [41.99844472131922]
We study the long-time dynamics of a one-dimensional discrete-time quantum walk under Pauli noise acting on the coin.<n>All channels induce a crossover from ballistic to diffusive spreading, with a second moment growing linearly at long times.<n>The quantum-to-classical transition is governed by the relative alignment of the noise, the coherent walk dynamics, and the initial state.
arXiv Detail & Related papers (2026-09-11T18:02:03Z) - Quantum Turing Patterns [0.0]
We construct quantum Turing patterns in Lindblad lattice dynamics and establish a rigorous theory of their nonlinear order and quantum fluctuations.<n>For an explicit family of completely positive lattice generators with finite-range couplings, the first-moment equations undergo a supercritical instability at a nonzero wave number.
arXiv Detail & Related papers (2026-07-28T23:05:00Z) - Stochastic Counterdiabatic Driving via Biorthogonal Liouvillian Eigenmodes [42.668742604089324]
Escorted free energy simulations address the non-adiabatic lag by engineering control fields $mathbfu$ that eliminate the lag.<n>We construct a complementary numerical framework based on gauge-type transforms instead of generalized coordinate transforms.<n>We show that the counterdiabatic condition is satisfied to machine precision, with the non-adiabatic lag suppressed by roughly twelve orders of magnitude.
arXiv Detail & Related papers (2026-07-27T13:08:14Z) - Driven Quantum Stars as Controlled Primitives for Real-Time Spin Dynamics [0.0]
Quantum advantage in real-time spin dynamics should be assessed against the strongest relevant classical substitutes.<n>We develop a physics-based diagnostic for this boundary by reducing a qubit spin model to a spin-Landau--Lifshitz (LL) classical sector.
arXiv Detail & Related papers (2026-07-12T19:58:56Z) - Sample Complexity of Policy Gradient for Log-Growth Control [23.86784769848408]
We study the sample complexity of policy gradient for log-growth control.<n>We prove that projected mini-batch policy gradient attains total sample complexity.
arXiv Detail & Related papers (2026-05-26T07:24:14Z) - Nonclassical Cutoff Fluctuations in Squeezed-Light-Driven High-Harmonic Generation [0.0]
We show that amplitude suppresses the shot-to-shot variance of the HHG cutoff below the standard quantum limit.<n>A sub phase-noise contribution from the anti-squeezed quadrature produces a variance minimum near r_opt 1.6, providing a concrete experimental target.
arXiv Detail & Related papers (2026-05-21T02:49:13Z) - Continuum field theory of matchgate tensor network ensembles [36.94429692322632]
We develop a continuum description for random ensembles of two-dimensional fermionic matchgate tensor networks.<n>As a diagnostic of the resulting universal physics, we analyze disorder-averaged moments of fermionic two-point functions.<n>We show that disorder drives universal long-distance behavior governed by a nonlinear sigma-model of symmetry class D with a topological term.
arXiv Detail & Related papers (2026-03-06T12:15:35Z) - Deep Sequence Modeling with Quantum Dynamics: Language as a Wave Function [0.0]
We introduce a sequence modeling framework in which the latent state is a complex-valued wave function evolving on a finite-dimensional Hilbert space under a learned, time-dependent Hamiltonian.<n> Token probabilities are extracted using the Born rule, a quadratic measurement operator that couples magnitudes and relative phases.<n>We derive a continuity equation for the latent probability mass, yielding conserved pairwise currents that serve as a built-in diagnostic.
arXiv Detail & Related papers (2026-02-24T23:42:18Z) - Stability and Generalization of Push-Sum Based Decentralized Optimization over Directed Graphs [55.77845440440496]
Push-based decentralized communication enables optimization over communication networks, where information exchange may be asymmetric.<n>We develop a unified uniform-stability framework for the Gradient Push (SGP) algorithm.<n>A key technical ingredient is an imbalance-aware generalization bound through two quantities.
arXiv Detail & Related papers (2026-02-24T05:32:03Z) - The Geometry of Noise: Why Diffusion Models Don't Need Noise Conditioning [20.547812775989808]
We study autonomous (noise-agnostic) generative models, such as Equilibrium Matching and blind diffusion.<n>We prove that generation using autonomous models is not merely blind denoising.<n>We also establish the structural stability conditions for sampling with autonomous models.
arXiv Detail & Related papers (2026-02-20T18:49:00Z) - Loschmidt Echo and Classicality of the Gamma Model [0.0]
The classicality of the Gamma Model is investigated using the overlap dynamics, also known as the Loschmidt Echo, and roughness, a classicality measure based on the Wigner representation of a state.<n>Though the overlap dynamics would indicate a chaotic regime, here the model is integrable.
arXiv Detail & Related papers (2025-12-19T21:42:07Z) - Non-Gaussian Phase Transition and Cascade of Instabilities in the Dissipative Quantum Rabi Model [2.821770504713635]
The open quantum Rabi model describes a two-level system coupled to a harmonic oscillator.<n>A Gaussian phase transition for the nonequilibrium steady states has been predicted when the bosonic mode is soft and subject to damping.<n>We show that oscillator dephasing is a relevant perturbation, which leads to a non-Gaussian phase transition and an intriguing cascade of instabilities for $k$-th order bosonic operators.
arXiv Detail & Related papers (2025-07-09T17:51:20Z) - Modelling 1/f Noise in TRNGs via Fractional Brownian Motion [1.3053649021965603]
Security of random number generators is not fully understood due to complex $1/falpha$ phase noise.<n>We introduce fractional Brownian motion as a comprehensive theoretical framework, capturing power-law spectral densities from white to flicker frequency noise.
arXiv Detail & Related papers (2024-10-18T06:38:34Z) - KPZ scaling from the Krylov space [83.88591755871734]
Recently, a superdiffusion exhibiting the Kardar-Parisi-Zhang scaling in late-time correlators and autocorrelators has been reported.
Inspired by these results, we explore the KPZ scaling in correlation functions using their realization in the Krylov operator basis.
arXiv Detail & Related papers (2024-06-04T20:57:59Z) - Matrix Denoising with Doubly Heteroscedastic Noise: Fundamental Limits and Optimal Spectral Methods [24.06775799553418]
We study the matrix denoising problem of estimating the singular vectors of a rank-$1$ signal corrupted by noise with both column and row correlations.
Our work establishes the information-theoretic and algorithmic limits of matrix denoising with doubly heteroscedastic noise.
arXiv Detail & Related papers (2024-05-22T18:38:10Z) - 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.