Expertini Research Research

Browse Research Papers

307+ open-access research outputs.

โœ• Clear
๐Ÿ” raphael feraud ๐Ÿ“‚ Mathematics
Showing 307 results for "raphael feraud" in Mathematics
Mathematics Preprint PDF DOI

Skew-orthogonal polynomials for a quartic Freud weight: two classes of quasi-orthogonal polynomials

Costanza Benassi, Marta Dell'Atti ยท 2026

This work is a thorough investigation of skew-orthogonal polynomials with respect to a quartic Freud weight. We provide an explicit method to evaluate skew-orthogonal polynomials of any degree as lineโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Algebraic numbers and Fourier analysis: Salem's third problem

Khoa D. Nguyen ยท 2026

In 1963, Rapha\"el Salem concluded his highly influential book ``Algebraic Numbers and Fourier Analysis'' with a list of four unsolved problems. The first two problems remain wide open while the last โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A simple approach to the L{\o}kka-Zervos dichotomy for absolutely continuous dividend strategies

Tommy Mastromonaco, Nacer Fendri, Jean-Francois Renaud, Clarence Simard ยท 2026

We revisit the optimization problem solved in L{\o}kka & Zervos (2008), i.e., the maximization of dividends, in a Brownian risk model, with the possibility (not the obligation) of making capital injecโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Geometry of the Donaldson-Friedman Pushout: Twistor degenerations and instanton charge

Amedeo Altavilla, Mauricio Correa ยท 2026

We study the singular central fibre arising in the Donaldson-Friedman construction for twistor spaces of connected sums, viewing it as a Ferrand pushout of two blown-up twistor spaces along the exceptโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Determinantally Equivalent Functions Beyond the Nowhere-Zero Case

Harry Sapranidis Mantelos ยท 2026

Let $\Lambda$ be a set and $\mathbb{F}$ a field, and suppose that $K,Q:\Lambda^2\to\mathbb{F}$ are two functions such that for any $n\in\mathbb{N}$ and $x_1,x_2,\ldots,x_n\in\Lambda$, the determinantsโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A universal bound on the blow-up rate for the focusing mass-critical nonlinear Schr\"odinger equation

Beomjong Kwak, Soonsik Kwon ยท 2026

In this paper, we investigate a universal blow-up bound for the focusing mass-critical nonlinear Schr\"odinger equation for general initial data in $L^2(\mathbb R^d)$, extending previous knowledge forโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Construction of two-bubble blow-up solutions for the mass-critical gKdV equations

Yang Lan, Xu Yuan ยท 2026

For the mass-critical generalized Korteweg-de Vries equation, $$ \partial_{t}u+\partial_{x}\left( \partial_{x}^{2}u+u^{5}\right)=0,\quad (t,x)\in [0,\infty)\times \mathbb{R}.$$ We prove the existence โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Central subspace data depth

Giacomo Francisci, Claudio Agostinelli ยท 2026

Statistical data depth plays an important role in the analysis of multivariate data sets. The main outcome is a center-outward ordering of the observations that can be used both to highlight features โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A hybrid-Hill estimator enabled by heavy-tailed block maxima

Claudia Neves, Chang Xu ยท 2025

When analysing extreme values, two alternative statistical approaches have historically been held in contention: the block maxima method (or annual maxima method, spurred by hydrological applications)โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Remarks on potential functions of noncompact quasi-Einstein manifolds

Jaciane Goncalves ยท 2025

In this article, we study the set of potential functions on noncompact quasi-Einstein manifolds. We show that the space of all positive potential functions on a three-dimensional noncompact quasi-Einsโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Full range of infinite point blow-up exponents for the critical generalized KdV equation

Nailya Manatova ยท 2025

For the quintic, mass critical generalized Korteweg-de Vries equation, for any $\nu \in (\frac{1}{2}, 1)$, we prove the existence of solutions in the energy space that blow up in finite time $T>0$ witโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

CLT for $\beta$-ensembles with Freud weights, application to the KLS conjecture in Schatten balls

Charlie Dworaczek Guera, Ronan Memin, Michel Pain ยท 2025

In this paper, we are interested in the $\beta$-ensembles (or 1D log-gas) with Freud weights, namely with a potential of the form $|x|^{p}$ with $p \geq 2$. Since this potential is not of class $\mathโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A local Lorentzian Ferrand-Obata theorem for conformal vector fields

Sorin Dumitrescu, Charles Frances, Karin Melnick, Vincent Pecastaing, Abdelghani Zeghib ยท 2025

For a conformal vector field on a closed, real-analytic, Lorentzian manifold we prove that the flow is locally isometric -- that it preserves a metric in the conformal class on a neighborhood of any pโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Formalization of Auslander--Buchsbaum--Serre criterion in Lean4

Naillin Guan, Yongle Hu ยท 2025

We present a comprehensive formalization in the Lean4 theorem prover of the Auslander--Buchsbaum--Serre criterion, which characterizes regular local rings as those Noetherian local rings with finite gโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A class of Truncated Freud polynomials

Juan Carlos Garcia-Ardila, Francisco Marcellan, Misael E. Marriaga ยท 2025

Consider the following truncated Freud linear functional $\mathbf{u}_z$ depending on a parameter $z$, $$\langle\mathbf{u}_z,p\rangle=\int_0^\infty p(x)e^{-zx^4}dx,\quad z>0.$$ The aim of this work is โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Nonhomothetic complete periodic metrics with constant scalar curvature

Joao H. Andrade, Jeffrey S. Case, Paolo Piccione, Juncheng Wei ยท 2025

We show that there are infinitely many pairwise nonhomothetic, complete, periodic metrics with constant scalar curvature that are conformal to the round metric on $S^n\setminus S^k$, where $k < \frac{โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

A novel approach through spherical functions in the characterization of invariant functions

Rocio Diaz Martin, Linda Saal ยท 2025

Given a compact subgroup K of the orthogonal group acting on the Euclidean space Rn, Gerald Schwarz proved that every smooth K-invariant function on Rn can be expressed as a smooth function of a generโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Polynomials and asymptotic constants in a resurgent problem from 't Hooft

David Broadhurst, Gergo Nemes ยท 2025

In a recent study of the quantum theory of harmonic oscillators, Gerard 't Hooft proposed the following problem: given $G(z)=\sum_{n=1}^\infty\sqrt{n}\,z^n$ for $|z|<1$, find its analytic continuationโ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

The strange story of an almost unknown prime number counter: The Rafael Barrett formula

Eduardo Mizraji ยท 2025

In this brief article, we present the formula created by Rafael Barrett in 1903 in a note to Henri Poincar\'e, which remained unknown for decades. Discovered in the 1930s by a Uruguayan mathematician,โ€ฆ

Read Paper โ†’
Mathematics Preprint PDF DOI

Disrupting the scammer lifecycle: A dynamically-consistent numerical analysis of a compartment model for scam-victim dynamics

Y.O. Tijani, I. Ghosh, S.D. Oloniiju, H.O. Fatoyinbo ยท 2025

Online deception and financial scams represent a pervasive threat in the digital age, yet a quantitative analysis and understanding of their propagation is lacking. This study introduces a novel modelโ€ฆ

Read Paper โ†’
Page 1 of 16 Next โ†’