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๐Ÿ” j. borges ๐Ÿ“‚ Mathematics
Showing 23087 results for "j. borges" in Mathematics
Mathematics Preprint PDF DOI

Stein's square function associated with the Bochner-Riesz means on M\'etivier groups and its applications

Joydwip Singh ยท 2026

In this paper, we study the $L^p$-boundedness of Stein's square function $\mathfrak{S}^{\alpha}(\mathcal{L})$ associated with the sub-Laplacian $\mathcal{L}$ on M\'etivier group $G$. A key aspect of oโ€ฆ

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Mathematics Preprint PDF DOI

A Ring structure on the Class of Combinatorial Games

Harry Altman, Paolo Lipparini ยท 2026

J. Conway defined useful operations on the Class of combinatorial games and also introduced a notion of equivalence between games. Conway showed that, under his equivalence, games form a Group. Howeveโ€ฆ

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Mathematics Preprint PDF DOI

Expected hyperbolic volumes of random beta polytopes

Zakhar Kabluchko, Philipp Schange ยท 2026

Let $X_1,\ldots,X_n$ be independent random points in the closed unit ball of $\mathbb{R}^d$. Assume that each $X_i$ has a beta distribution with parameter $\beta_i \ge -1$: if $\beta_i>-1$, then $X_i$โ€ฆ

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Mathematics Preprint PDF DOI

A divisor function of Wigert and higher degree forms

Debika Banerjee, Atul Dixit, Rajat Gupta ยท 2026

Let $k\in\mathbb{N}$. Wigert's divisor function $d^{\left(\frac{1}{k}\right)}(j)$ counts the number of representations of $j$ of the form $m^k+mn$ with $m\geq1 , n\geq0$. Let $\mathcal{F}_k(s)$ denoteโ€ฆ

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Mathematics Preprint PDF DOI

Hirzebruch $\chi_{y}$-genus of compact almost K\"{a}hler manifold with negative sectional curvature

Teng Huang, Pan Zhang ยท 2026

Let \((X,J,\omega)\) be a closed \(2n\)-dimensional almost K\"{a}hler manifold with negative sectional curvature. We prove that if the Nijenhuis tensor of the almost complex structure is sufficiently โ€ฆ

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Mathematics Preprint PDF DOI

Flat coordinates of Frobenius prepotentials related with the reflection groups of types $H_3$ and $H_4$

Rei Aradachi, Hiromasa Nakayama, Jiro Sekiguchi ยท 2026

In this article, we first explain a group theoretic interpretation of the derivation of the relation between the flat coordinates of the polynomial prepotential $(H_3)$ and those of the algebraic prepโ€ฆ

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Mathematics Preprint PDF DOI

Syzygies of the transfer ideal of the symmetric group

Harm Derksen, Alexandra Pevzner ยท 2026

We consider the modular action of the symmetric group $S_n$ on $R = k[x_1,\ldots,x_n]$ when $\mathrm{char}(k) = p \leq n$. We show that the image of the transfer map $R\to R^{S_n}$ is an elimination iโ€ฆ

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Mathematics Preprint PDF DOI

The maximum size of the partial ground set of skew Bollob\'{a}s systems

Yu Fang, Tao Feng, Xiaomiao Wang ยท 2026

A skew Bollob\'{a}s system $\mathcal{P}=\{(A_i,B_i):1\leq i\leq m\}$ is a collection of pairs of disjoint subsets of $[n]$ such that $A_i\cap B_j\ne\emptyset$ for any $1\leq i<j\leq m$. Denote by $S_1โ€ฆ

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Mathematics Preprint PDF DOI

Exact Flatness Constant for One-Point Convex Bodies and the Discrete Isominwidth Problem: The Planar Case

Gennadiy Averkov, Giulia Codenotti, Ansgar Freyer, Kyle Huang ยท 2026

A variant of the flatness problem from integer programming is studied, in which one considers convex bodies in $\mathbb{R}^d$ with at most $k$ interior lattice points. The maximum lattice width of sucโ€ฆ

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Mathematics Preprint PDF DOI

An Analysis of the Diaconis-Holmes-Neal Markov Chain Sampler Under Generalized Unimodal Underlying Probabilities

Martin V. Hildebrand, Christopher J. Lange ยท 2026

Upon the introduction of the Metropolis algorithm, the question of how many steps in the Markov chain were needed to achieve convergence to stationarity became apparent. The convergence was rather sloโ€ฆ

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Mathematics Preprint PDF DOI

Operator-Valued Positivstellens\"atze on Matrix Convex Sets and Free Products of Finite Abelian Groups

Abhay Jindal, Igor Klep, Scott McCullough ยท 2026

We prove a Positivstellensatz for operator-valued noncommutative polynomials that are positive on matrix convex sets. Specifically, let $p$ be an operator-valued polynomial in $B(H)\otimes C<x>$ of deโ€ฆ

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When all parallel sets of a $ C^1 $-hypersurface are nowhere $ C^1 $-regular

Mario Santilli ยท 2026

We prove a necessary and sufficient condition for a $ C^1 $-hypersurface to have all parallel sets nowhere $ C^1 $-regular. As a corollary, we deduce that for a generic $ C^1 $-regular convex body allโ€ฆ

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Lagrangian reduction of symmetric discrete mechanical systems: a survey

Matias I. Caruso, Javier Fernandez, Cora Tori, Marcela Zuccalli ยท 2026

In this note we survey some of our results on the Lagrangian reduction of discrete-time mechanical systems (DMSs). It is intended as an introduction to the general ideas that we used in the reduction โ€ฆ

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A mathematical study of an elastic-viscous-plastic sea-ice model with the Kelvin-Voigt rheology

Daniel W. Boutros, Xin Liu, Marita Thomas, Edriss S. Titi ยท 2026

Motivated by the elastic-viscous-plastic (EVP) sea-ice model [E. C. Hunke and J. K. Dukowicz, J. Phys. Oceanogr., 27, 9 (1997), 1849--1867], which is used in large-scale numerical climate simulations,โ€ฆ

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Non-uniqueness of nonlinear Markov processes in the sense of McKean associated with parabolic PDEs

Ehsan Abedi, Florian Bechtold, Marco Rehmeier ยท 2026

We derive a general scheme to construct infinitely many probabilistic counterparts for solutions to nonlinear PDEs by recasting the latter as different nonlinear Fokker--Planck equations and by constrโ€ฆ

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Boundary epsilon regularity for incompressible Navier--Stokes equations via weak-strong uniqueness

Siran Li ยท 2026

We show that finite-energy weak solutions to the incompressible Navier--Stokes equations on a three-dimensional bounded smooth domain are regular up to the boundary, provided that the $L^4_tL^4_x$-norโ€ฆ

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The Divisor Function along a Deterministic Orbit and the Emergence of Ladders

Marco Mantovanelli ยท 2026

We study the deterministic recursion $n_{j+1} = n_j - \tau(n_j)$, where $\tau(n)$ denotes the divisor function, and the associated orbit length $a(x)$. Heuristics based on the average order of $\tau(nโ€ฆ

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Convergence analysis of a full discretization of operator-valued differential Riccati equations

Eskil Hansen, Tony Stillfjord, Teodor {AA}berg ยท 2026

In recent previous work [E. Hansen, T. Stillfjord and T. \r{A}berg, SIAM J. Numer. Anal., to appear], we analyzed the convergence of operator splitting methods applied to operator-valued differential โ€ฆ

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On rates of convergence for sample average approximations without smoothness

Hien Duy Nguyen, Jacob Westerhout, Xin Guo ยท 2026

Sample average approximation (SAA) replaces an intractable expected objective by an empirical average and is a basic device of modern stochastic optimization. We develop a rate theory for optimal valuโ€ฆ

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A nonlocal coupled system: analysis and discretization

Francisco Bersetche, Enrique Otarola, Daniel Quero ยท 2026

We analyze a nonlocal coupled system arising as the Euler--Lagrange equations of an energy functional involving regional fractional Laplacians of orders $s_1$ and $s_2$ ($ 0 < s_1,s_2 < 1$), each actiโ€ฆ

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