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Physics Preprint PDF DOI

Domain-wall melting in all-to-all QSSEP from random-matrix theory

Denis Bernard, Lorenzo Piroli, Stefano Scopa · 2026

We study the melting of a domain wall in the quantum simple exclusion process with all-to-all hoppings (a.k.a. the charged SYK$_2$ model). We show that the real-time dynamics of physical quantities of…

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Mathematics Preprint PDF DOI

Gauge symmetry and uniqueness in inverse problems for the JMGT equation

Dong Qiu, Xiang Xu, Yeqiong Ye, Ting Zhou · 2026

In this paper, we study an inverse boundary value problem for the Jordan--Moore--Gibson--Thompson equation on a simple Riemannian manifold. We consider an all boundary measurement map that maps Dirich…

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Physics Preprint PDF DOI

Mixture-aware closure of the N-phase Navier--Stokes--Cahn--Hilliard mixture model

M.F.P. ten Eikelder, A. Brunk · 2026

Diffuse-interface (phase-field) models are widely used to describe multiphase mixtures and their interfacial dynamics. In multiphase settings, however, the constitutive closure should remain meaningfu…

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Physics Preprint PDF DOI

High-Girth Regular Quantum LDPC Codes from Square-Base Hypergraph Products via CPM Lifts

Koki Okada, Kenta Kasai · 2026

We study square-base Calderbank--Shor--Steane (CSS) hypergraph-product codes as a finite-length class for regular high-girth quantum low-density parity-check (LDPC) design. For base matrices of small …

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Mathematics Preprint PDF DOI

Finite-time blow-up in a class of chemotaxis systems with spatially heterogeneous diffusion sensitivity

Yashuang Zhao, Shijun Li, Shaopeng Xu · 2026

\indent In this paper, we study a class of parabolic-elliptic Keller-Segel systems with diffusion sensitivity dependent on spatial position, given by type \begin{equation} \left\{ \begin{array}{ll…

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Physics Preprint PDF DOI

Asymmetric freezing of a sliding droplet on an inclined surface

Sivanandan Kavuri, George Karapetsas, Chander Shekhar Sharma, Kirti Chandra Sahu · 2026

We investigate the asymmetric freezing of a liquid droplet sliding on an inclined cold surface using numerical simulations based on the lubrication approximation. The combined effects of gravity, capi…

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Mathematics Preprint PDF DOI

Lipschitz Stability of boundary measurements for unknown constant polygonal conductivity inclusions

Tianrui Dai, Elisa Francini · 2026

In this work, we derive the Lipschitz stability for conductivities of unknown constants as well as unknown polygonal inclusions from the Dirichlet-to-Neumann map.…

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Mathematics Preprint PDF DOI

Global boundedness and asymptotic behavior of the chemotaxis system for Alopecia Areata with weakly singular sensitivity

Pengxue Xiang, Yuebo Cao, Hongying Yang · 2026

This paper considers the homogeneous Neumann initial-boundary value problem for Alopecia Areata chemotaxis model with weakly singular sensitivity. For any appropriately regular initial conditions,it i…

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Mathematics Preprint PDF DOI

The local Calder\'on problem and the determination at the boundary of a complex anisotropic admittivity

Jessica Crosse, Romina Gaburro · 2026

We address Calder\'on's problem of stably determining the anisotropic complex admittivity $\sigma$ in a domain $\Omega\subset\mathbb{R}^n$, with $n\geq3$, representing a conducting medium, in terms of…

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Mathematics Preprint PDF DOI

On a conjecture of distance spectral extremal problems

Hongzhang Chen, Jianxi Li, Yongtao Li · 2026

Brualdi and Hoffman proposed a well-known problem of determining the graph with maximum adjacency spectral radius among all graphs with given size $m$. Early work by Friedland and Stanley addressed so…

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Mathematics Preprint PDF DOI

The Neumann problem for the generalized H\'enon equation. Local analysis

Alexander I. Nazarov, Alexandra P. Shcheglova · 2026

For the boundary value problem $$\left\{ \begin{array}{rcll} -\Delta_p u+u^{p-1}&=&|x|^{\alpha}u^{q-1}&\mbox{in }\Omega,\\ \frac{\displaystyle\partial u}{\displaystyle\partial{\bf n}}&=&0&\mbox{on }\p…

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Mathematics Preprint PDF DOI

$T$-admissible processes and noncommutative weighted ergodic theorems

Morgan O'Brien · 2026

In this article, we study the bilaterally almost uniform (b.a.u.) convergence of weighted averages of a positive Dunford-Schwartz operator on the noncommutative $L_p$-spaces associated to a semifinite…

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Mathematics Preprint PDF DOI

Unitary representations and von Neumann's continuous geometries

Friedrich Martin Schneider, Andreas Thom · 2026

We prove that the unit group of a non-discrete irreducible, continuous ring, in the sense of John von Neumann, does not admit any non-trivial unitary representation continuous with respect to the stro…

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Physics Preprint PDF DOI

Solving a Linear System of Equations on a Quantum Computer by Measurement

Alain Giresse Tene, Thomas Konrad · 2026

We present a variational algorithm for fault tolerant quantum computing to solve a system of linear equations which directly maximises the parameters of the target fidelity. This so-called measurement…

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Computer Science Preprint PDF DOI

A dynamic $(1+\varepsilon)$-spanner for disk intersection graphs

Sarita de Berg, Ivor van der Hoog, Eva Rotenberg, Johanne M. Vistisen, Sampson Wong · 2026

We maintain a $(1+\varepsilon)$-spanner over the disk intersection graph of a dynamic set of disks. We restrict all disks to have their diameter in $[4,\Psi]$ for some fixed and known $\Psi$. The resu…

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Mathematics Preprint PDF DOI

Pointwise Convergence for Random Ergodic Averages in Non-commutative $L^p$-spaces

Christian Le Merdy, Safoura Zadeh · 2026

Let $M$ be a semifinite von Neumann algebra and $T$ a positive contraction on both $L^1(M)$ and $L^\infty(M)$. We consider ergodic averages along a random sparse subsequence determined by independent …

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Mathematics Preprint PDF DOI

Invariant trace simplices and relative property (T)

Raz Slutsky · 2026

Let $\alpha\colon G\curvearrowright A$ be an action of a countable discrete group on a separable unital $C^*$-algebra. We study the simplex $\mathrm{T}(A)^G$ of $G$-invariant traces and ask when it is…

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Physics Preprint PDF DOI

Operating a contextual Stern-Gerlach apparatus

Th. K. Mavrogordatos · 2026

We propose a contextual cavity/circuit QED analogue and extension of the Stern-Gerlach experiment, where the pseudo-spin of a two-state `atomic' transition plays the role of the ``spin'', while the re…

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Physics Preprint PDF DOI

Field-theoretical description of the deuteron breakup in the clothed particle representation

O. Shebeko, A. Arslanaliev, Y. Kostylenko, V. Chahar, J. Golak, H. Kamada, W. N. Polyzou, D. Ramirez, R. Skibinski, K. Topolnicki, H. Wita{l}a · 2026

We present a field-theoretical description of the deuteron electrodisintegration reaction d(e,e'p)n induced by unpolarized and polarized electrons. The approach combines the Lehmann-Symanzik-Zimmerman…

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Mathematics Preprint PDF DOI

Vanishing interfaces in an asymmetric fast reaction limit

Yuki Tsukamoto · 2026

We study the fast reaction limit for a two-component reaction-diffusion system with asymmetric reaction terms, where only one component diffuses. For nonnegative and mutually segregated initial data, …

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