Quadratic form of heavy-tailed self-normalized random vector with applications in α\alpha-heavy Mar\v cenko--Pastur law

This paper establishes that the asymptotic distribution of quadratic forms for self-normalized heavy-tailed random vectors is determined solely by the diagonal entries of the matrix and the stability index α\alpha, a result applied to derive the atom-free nature of the α\alpha-heavy Marčenko--Pastur law for heavy-tailed sample correlation matrices.

Zhaorui Dong, Johannes Heiny, Jianfeng YaoTue, 10 Ma🔢 math

Parameter-related strong convergence rates of Euler-type methods for time-changed stochastic differential equations

This paper proposes an Euler-type framework with equidistant step sizes for time-changed stochastic differential equations, establishing that both the standard and truncated Euler–Maruyama methods achieve strong convergence rates close to α/2\alpha/2 under global Lipschitz and relaxed Khasminskii-type conditions, respectively, which contrasts with the classical $1/2$ order found in methods using random step sizes.

Ruchun ZuoThu, 12 Ma🔢 math

The discrete periodic Pitman transform: invariances, braid relations, and Burke properties

This paper establishes the theory of the discrete periodic Pitman transform by proving its braid relations, defining an infinite symmetric group action, and demonstrating multi-path invariance for periodic polymer models through a new inhomogeneous Burke property.

Eva R. Engel, Benjamin Jasper Kra-Caskey, Oleksandr Lazorenko, Caio Hermano Maia de Oliveira, Evan Sorensen, Ivan Wong, Ryan Xu, Xinyi ZhangThu, 12 Ma🔢 math

Some properties of the principal Dirichlet eigenfunction in Lipschitz domains, via probabilistic couplings

This paper establishes uniform regularity estimates for the principal Dirichlet eigenfunctions of both discrete random walks and continuous Brownian motion in Lipschitz domains by employing a novel probabilistic approach combining Feynman-Kac representations, gambler's ruin estimates, and a new "multi-mirror" coupling, while also reviewing convergence results between the discrete and continuous eigenfunctions.

Quentin Berger, Nicolas BouchotThu, 12 Ma🔢 math

Solution space characterisation of perturbed linear discrete and continuous stochastic Volterra convolution equations: the p\ell^p and LpL^p cases

This paper characterizes the solution spaces of perturbed linear stochastic Volterra equations in discrete and continuous time, establishing that while pp-summable perturbations are necessary and sufficient for almost sure pp-summability in the discrete case, the continuous case allows for almost sure pp-integrability even with non-integrable perturbations, a result proven via discretization and extended to analyze asymptotic convergence and broader functional differential equations.

John A. D. Appleby, Emmet LawlessThu, 12 Ma🔢 math

Intermittent Cauchy walks enable optimal 3D search across target shapes and sizes

This paper mathematically proves that in three-dimensional space, the Cauchy walk (Lévy exponent μ=2\mu=2) uniquely achieves scale-invariant, near-optimal detection across diverse target sizes and shapes by transitioning from volume-dominated to surface-area-dominated search strategies, thereby establishing a rigorous foundation for the Lévy flight foraging hypothesis in 3D.

Matteo Stromieri, Emanuele Natale, Amos KormanThu, 12 Ma🔢 math

An asymptotically optimal bound for the concentration function of a sum of independent integer random variables

This paper proves an asymptotically optimal bound for the concentration function of a sum of independent integer random variables, confirming that the sum's maximum point probability is bounded by that of a corresponding sum of minimal-variance variables when the total variance is sufficiently large, thereby extending the result to separable Hilbert spaces.

Valentas KurauskasThu, 12 Ma🔢 math