1645542 results (page 2 of 65822)
-
Thermalization of open quantum systems with pseudomodes
Pseudomode approaches allow for an exact and unapproximated description of a quantum system interacting arbitrarily strongly with a bath. In general, a system coupled to pseudomodes will not thermalize to the system's Gibbs state: This is to be expected when the system-bath coupling is non-perturbative, but conflicts with common thermodynamic intuition when the system-bath coupling is asymptotical…
-
Comparison of Lindblad and circuit approaches for quantum heat transport
We compare two popular models applicable to analyzing heat transport by thermal microwave photons in quantum circuits. The first model is derived from a weak-coupling Lindblad master equation, with transition rates determined by Fermi's golden rule induced by thermal dissipation sources. The second approach employs a circuit model, where thermal Johnson-Nyquist noise generated by dissipative eleme…
-
Beyond Modern Asymptotics for Log-Likelihood Ratios in Logistic Regression
We characterize the finite sample behavior of the log-likelihood ratio statistic in binary logistic regression, uniformly over both the design and the target parameter. For $n\geq d\geq 3$, we determine, up to universal constants, its worst case $(1-δ)$ quantile over all fixed collections of design vectors and all target parameters: \[ d\log\left(\frac{e n}{d}\right)+\log\left(\frac{1}δ\right). \]…
-
A simplified min-max formula for the inverse arborescence problem
A simple min-max theorem is formulated and proved for the smallest modification (measured in $l_1$-norm) of an input cost function $w_0$ that makes a target arborescence $F_0$ of a digraph a cheapest arborescence. The constructive proof gives rise to a polynomial time algorithm for computing both a minimizer cost function on the primal side and a maximizer dual object in the min-max formula.
-
Isogeny graphs of elliptic curves in characteristic zero
For an elliptic curve $E$ defined over a field $K$ of characteristic $0$ with $\operatorname{End}_K \! E \cong \mathbb{Z}$, we classify which isogeny graphs $\mathcal{G}(E/K)$ can occur. We first show that $\mathcal{G}(E/K)$ decomposes as a weak Cartesian product of its $p$-primary isogeny graphs, one for each prime $p$, thereby reducing the problem to classifying $p$-primary isogeny graphs. We th…
-
Hidden Star-Convexity in Policy Optimization for Gain-Scheduled LQR: Extended Version
We study policy optimization for gain-scheduled linear quadratic regulation, where one schedule of gains, interpolated through fixed weighting functions, is optimized against a family of plants. The resulting cost can develop spurious local minima, and existing convergence certificates are either local or severely conservative. We establish an exact identity: when the gradient of the cost is evalu…
-
High-dimensional quantum process tomography with undetected photons
The goal of quantum process tomography is to fully characterize an operation performed on a quantum state. By considering high-dimensional quantum states (qudit), we show that it is possible to fully reconstruct an arbitrary operation without performing any measurement on the transformed qudit. Our method is interferometric and conceptually different from existing techniques of quantum process tom…
-
Computational and Statistical Guarantees of the \textit{c}-Rectified flow
Recently, rectified flow has emerged as a fundamental framework for large-scale image generation, powering state-of-the-art systems such as FLUX.1 and Stable Diffusion 3. Despite its remarkable empirical success, the computational and statistical guarantees of iterative rectified flow have remained largely unexplored. We address this problem by studying \textit{c}-rectified flow, a cost-aware clas…
-
Response to: "Isotropic deceleration and near-zero baseline acceleration in Pantheon+ supernovae: new arguments in the dark energy debate''
Ray et al. [1] have claimed that the acceleration of the Hubble expansion rate inferred from Type Ia supernovae in the Pantheon+ catalogue "is equally strong in the CMB dipole ($q_m = + 1.45$) and anti-dipole hemispheres ($+ 1.55$), directly contradicting the SRS26 anisotropy argument". Here SRS26 refers to our analysis [2] which showed that "locally $q_0$ has a strong dipole anisotropy aligned ap…
-
Fermat Active Laplace Learning for Semi-Supervised Hyperspectral Image Classification
Two active learning algorithms for hyperspectral image (HSI) classification are proposed that combine density-aware Fermat distances with Poisson-reweighted harmonic label propagation. Our methods actively query points using an uncertainty-based acquisition function, extending Poisson ReWeighted Laplace Learning (PWLL). Our first algorithm, Fermat Active Laplace Learning (FALL), builds an affinity…
-
A parity selection rule for regular black holes
Regular black hole metrics are usually studied kinematically, but a finite-curvature static core does not guarantee that the underlying theory can consistently evolve generic matter through a regular center. We derive a necessary local consistency condition within the most general class of action-based, identically conserved, second-order gravitational field equations in spherical symmetry. Regula…
-
Private Generative Bootstrap via Blocking
With AI systems gaining more access to individuals' information, it is important to protect privacy when reporting statistical answers. Equally important is to privatize the reporting of uncertainty in such answers. To this end, we adopt a Bayesian likelihood-free framework and make simulation from the posterior private. In particular, we propose a new private instantiation of the Bayesian bootstr…
-
Optimized Tensor-Network Renormalization for Quantum Dynamics: Resolving the Spectral Function of $\mathrm{K_2Co(SeO_3)_2}$
Tensor-network methods have opened a powerful route for the study of dynamical spectral functions in two-dimensional quantum systems. However, existing approaches within the framework of infinite projected entangled-pair states construct the required renormalization tensors solely from the ground-state environment and can suffer from severe numerical instability. We identify the origin of this ins…
-
Determination of the Representative Sample Size in Linear Regression
Very often, accuracy of analysis and forecasting (multiple coefficient of regression and residual means) obtained for a sample used to formulate a regression model is not equal to the accuracy achieved for another homogeneous sample. Indeed, accuracy of analysis and forecasting based on another sample is much worse. This is explained by the discrepancy between a postulated and a real model. This d…
-
NeuroInspector: A Local-First Environment for Inspecting and Annotating Hierarchical Neuroscience Datasets
The growing scale and structural complexity of neuroscience datasets have made dataset inspection an increasingly distinct stage of the research workflow. Existing inspection workflows, however, remain fragmented, often relying on exploratory scripts, manual documentation, and repeated navigation of unfamiliar file structures before meaningful scientific analysis can begin. Here we present NeuroIn…
-
Nanohertz Pendulum toward Macroscopic Entanglement under Structural Damping
Pendulums are attractive for macroscopic quantum control because gravity dilution reduces mechanical loss, while the $1/f$ force-noise spectrum associated with structural damping allows nearly lossless trapping to suppress the thermal noise sampled at an upward-shifted resonance. The same $1/f$ spectrum, however, produces a low-frequency tail that penalizes entanglement. With $10\%$ detection loss…
-
A Response Calculus for Liouville Brownian Motion I: Simple Spectrum, Joint Eigenvalue Densities, and Ward Identities
We develop a response calculus for Dirichlet Liouville Brownian motion under Cameron--Martin shifts of the Gaussian free field. On every bounded connected planar domain, without boundary regularity assumptions, we prove throughout the full subcritical range $0<γ<2$ that the generator has almost surely simple spectrum and that every finite vector of ordered eigenvalues has an absolutely continuous …
-
Isotropic universes with a preferred direction
We present a class of cosmological scenarios in which a preferred spatial direction in the matter sector coexists with an exactly homogeneous and isotropic Friedmann--Lemaître--Robertson--Walker (FLRW) geometry. The Cosmological Principle is realized on shell, with the vector-field equations enforcing a vanishing momentum density and suitable interactions eliminating the anisotropic stress. Conseq…
-
Aggregate-then-Calibrate for Human-centered Assessment with Theoretical Guarantees
Human-centered assessment tasks, which are essential for systematic decision-making, rely heavily on human judgment and typically lack verifiable ground truth. Existing approaches face a dilemma: methods using only human judgments suffer from heterogeneous expertise and inconsistent rating scales, while methods using only model-generated scores must learn from imperfect proxies or incomplete featu…
-
Spread complexity as a probe in generalized and long-range Aubry-Andre-Harper models
We investigate the spread complexity of quantum quenches in generalized and long-range Aubry-Andre-Harper (AAH) models, encompassing regimes with and without mobility edges. In particular, in the generalized AAH models supporting energy-dependent mobility edges, we demonstrate that the long-time averaged spread complexity exhibits nonanalytic behavior when the post-quench quasiperiodic potential c…
-
PhaseLift for Coded Diffraction Patterns: Optimal Sampling Rate
Recovering a complex-valued signal from coded diffraction patterns, namely the Fourier intensities obtained after modulating the signal with a collection of masks, is a fundamental structured phase retrieval problem arising in diffraction imaging and related applications. Despite its practical importance, the theoretical analysis of this structured framework remains scarce. In the standard random …
-
Minkowski decomposability of symmetric edge polytopes
In this paper, we study the Minkowski decomposability of symmetric edge polytopes $P_G^\pm$ of a finite simple graph $G$ on vertex set $[n]$. More precisely, we give a complete characterization of graphs whose symmetric edge polytopes are Minkowski decomposable. We prove that $P_G^\pm$ is Minkowski decomposable if and only if $G$ is one of the three complete multipartite graphs: $K_n$, $K_{2,n-2}$…
-
Timescale Separation Through the Lens of Operator Theory
Timescale separation is a powerful tool for analyzing interconnected dynamical systems. Meanwhile, operator theory provides a general framework for studying the convergence of iterative methods formulated as fixed-point iterations, including algorithms arising in optimization, learning, and control. In this paper, we bridge these two areas by establishing timescale separation results for fixed-poi…
-
Detecting high-dimensional entanglement with simple measurements
The standard benchmark for high-dimensional entanglement is the number of dimensions in which entanglement must be present in order to generate the state. This is called the Schmidt number and its detection is usually based on implementing an appropriate set of local basis measurements. However, as quantum technology brings increasingly large physical dimensions within reach, the implementation of…
-
Wasserstein mixing time of the unadjusted Langevin algorithm
We provide new estimates in Wasserstein distance for the asymptotic bias of the unadjusted Langevin algorithm, in the classical setting of log-smooth strongly log-concave measures. Our bound implies a Wasserstein mixing time of order $κ\sqrt{d}/\varepsilon$, where $κ$ is the condition number, $d$ is the dimension, and $\varepsilon$ is the target precision: this improves by a factor of $\sqrt{d}/\v…