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Mathematics Preprint PDF DOI

Cusp Form Dimensions, Lattice Uniqueness, and LP Sharpness for Sphere Packing in Dimensions 8 and 24

Jian Zhou ยท 2026

The Cohn-Elkies linear programming (LP) bound for sphere packing is known to be sharp in dimensions 8 and 24 but in no other dimension above 2. We investigate why by examining three independent necessโ€ฆ

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Physics Preprint PDF DOI

Complementary Quantum Time Distributions from a Single Operational Protocol

Mathieu Beau ยท 2026

A single operational protocol based on free evolution and projective measurements yields inequivalent quantum time distributions through distinct post-processing procedures. We construct an activity-bโ€ฆ

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Mathematics Preprint PDF DOI

Hartman-Stampacchia theorem, Gale-Nikaido-Debreu lemma, and Brouwer and Kakutani fixed-point theorems

Pascal Gourdel (PSE, CES), Cuong Le Van (CNRS, PSE, CES), Ngoc-Sang Pham (EM Normandie), Cuong Tran Viet (UP1 UFR02, CES) ยท 2026

This paper uses the Hartman-Stampacchia theorems as the primary tool to prove the Gale-Nikaid{\^o}-Debreu lemmas. It also establishes a cycle of equivalences among the Hartman-Stampacchia theorems, thโ€ฆ

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Mathematics Preprint PDF DOI

Stationary boundaries on the space of amenable subgroups and C*-simplicity

Anna Cascioli, Martin Gilabert Vio, Eduardo Silva ยท 2026

We give a sufficient condition for a countable group $G$ to possess a probability measure $\mu$ that admits a non-trivial $\mu$-boundary modeled in the space $\mathrm{Sub}_{\mathrm{am}}(G)$ of amenablโ€ฆ

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Physics Preprint PDF DOI

Single-star optical turbulence profiling techniques for the SHIMM and other Shack-Hartmann instruments

Ryan Griffiths, Timothy Butterley, Richard Wilson, James Osborn ยท 2026

Atmospheric optical turbulence (OT) monitoring is crucial for site characterisation at astronomical observatories and optical communications ground stations. The Shack-Hartmann Image Motion Monitor (Sโ€ฆ

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Mathematics Preprint PDF DOI

Symmetry properties for positive solutions of mixed boundary value problems in a sub-spherical sector

Ruofei Yao ยท 2026

In this paper, we investigate the symmetry properties of positive solutions $u$ to a semilinear elliptic equation under mixed Dirichlet-Neumann boundary conditions in symmetric domains. First, we estaโ€ฆ

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Computer Science Preprint PDF DOI

Interpretive Cultures: Resonance, randomness, and negotiated meaning for AI-assisted tarot divination

Matthew Prock, Ziv Epstein, Hope Schroeder, Amy Smith, Cassandra Lee, Vana Goblot, Farnaz Jahanbakhsh ยท 2026

While generative AI tools are increasingly adopted for creative and analytical tasks, their role in interpretive practices, where meaning is subjective, plural, and non-causal, remains poorly understoโ€ฆ

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Physics Preprint PDF DOI

Super-resolution wavefront reconstruction in adaptive-optics with pyramid sensors

Carlos M. Correia, Charlotte Z. Bond, Joao Aveiro, Francois Leroux, Cedric Taissir Heritier, Christophe Verinaud ยท 2025

Super-resolution (SR) refers to a combination of optical design and signal processing techniques jointly employed to obtain reconstructed wave-fronts at a higher-resolution from multiple low-resolutioโ€ฆ

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Physics Preprint PDF DOI

Entanglement surfaces for rotating cylindrical black holes

Fabio Billiato, Alessandra Gnecchi ยท 2025

We construct entanglement surfaces for rotating cylindrical black holes in a double holographic setup, extending previous results to the case of stationary backgrounds. We analyze both the 5d braneworโ€ฆ

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Physics Preprint PDF DOI

Revisiting the $k$-theorem with the ANEC

Nanami Nakamura, Yu Nakayama, Ung Nguyen ยท 2025

The fundamental theorem in renormalization group flows in two dimensions is the $c$-theorem, which dictates that the number of degrees of freedom must decrease monotonically along the renormalization โ€ฆ

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Mathematics Preprint PDF DOI

Non-commutative Law of iterated logarithm

Sourav Panja, Eric Ricard, Diptesh Saha ยท 2025

We prove optimal non-commutative analogues of the classical Law of Iterated Logarithm (LIL) for both martingales and sequences of independent (non-commutative) random variables. The classical martingaโ€ฆ

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Mathematics Preprint PDF DOI

$C^{1}$ Smoothness of the Conjugacy in a Delayed Nonautonomous Hartman--Grobman Theorem via $\mu$-Dichotomies

Alvaro Castaneda, Heli Elorreaga ยท 2025

We investigate the differentiability of the conjugacy in a nonautonomous version of the Hartman--Grobman Theorem for systems with finite delay, where the linear part satisfies a $\mu$-dichotomy. Underโ€ฆ

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Mathematics Preprint PDF DOI

On Minkowski's monotonicity problem

Ramon van Handel, Shouda Wang ยท 2025

We address an old open question in convex geometry that dates back to the work of Minkowski: what are the equality cases of the monotonicity of mixed volumes? The problem is equivalent to that of provโ€ฆ

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Mathematics Preprint PDF DOI

A generalized global Hartman-Grobman theorem for asymptotically stable semiflows

Wouter Jongeneel ยท 2025

Recently, Kvalheim and Sontag provided a generalized global Hartman-Grobman theorem for equilibria under asymptotically stable continuous vector fields. By leveraging topological properties of Lyapunoโ€ฆ

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Mathematics Preprint PDF DOI

Hartman-Grobman Theorem for Stochastic Dynamical Systems

Paul Bekima ยท 2025

In this paper, we extend the Hartman-Grobman theorem to systems perturbed with white noises. Let's recall that, in deterministic systems, the Hartman-Grobman theorem establishes the "topological equivโ€ฆ

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Mathematics Preprint PDF DOI

Error bound for the asymptotic expansion of the Hartman-Watson integral

Dan Pirjol ยท 2025

This note gives a bound on the error of the leading term of the $t\to 0$ asymptotic expansion of the Hartman-Watson distribution $\theta(r,t)$ in the regime $rt=\rho$ constant. The leading order term โ€ฆ

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Physics Preprint PDF DOI

Tunneling time in non-Hermitian space fractional quantum mechanics

Mohammad Umar, Vibhav Narayan Singh, Bhabani Prasad Mandal ยท 2025

We investigate the tunneling time of a wave packet propagating through a non-Hermitian potential $V_{r} - iV_{i}$ in space-fractional quantum mechanics. By applying the stationary phase method, we derโ€ฆ

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Physics Preprint PDF DOI

Investigating the role of mutual information in the Page curve for a functional renormalization group improved Schwarzschild black hole

Ashis Saha, Anirban Roy Chowdhury, Sunandan Gangopadhyay ยท 2025

The present work delves into probing the importance of mutual information of relevant subsystems in obtaining the correct time-evolution of fine-grained entropy of Hawking radiation, as suggested by Pโ€ฆ

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Physics Preprint PDF DOI

$\kappa$-Entanglement Entropy from Black Hole

Fabiano F. Santos, Ankit Anand ยท 2025

In this work, we explore the entanglement entropy equipped with the $\kappa$-algebra. This entanglement entropy is computed through the geometric setup as performed by Hartman-Maldacena, which, in theโ€ฆ

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Physics Preprint PDF DOI

c-theorem and improvement in non-compact conformal field theories

Nanami Nakamura, Yu Nakayama ยท 2025

Energy-momentum tensor in general conformal field theories have improvement ambiguity and it can affect the argument in deriving $c$-theorem. While the derivation of Zamolodchikov's c-theorem is stillโ€ฆ

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