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๐Ÿ” b. aringer ๐Ÿ“‚ Mathematics
Showing 38038 results for "b. aringer" in Mathematics
Mathematics Preprint PDF DOI

On centered local $\pi$-bases

Nathan Carlson ยท 2026

In 1967 Hajnal and Juh{\'a}sz showed that the cardinality of a first-countable Hausdorff space with the countable chain condition has cardinality at most $\mathfrak{c}$, the cardinality of the real liโ€ฆ

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Mathematics Preprint PDF DOI

A torsion-intersection proof of perfect-cuboid nonexistence on 1,072 explicit master-tuple fibers

Rene Peschmann ยท 2026

Building on the genus-3 reduction $C_A : w^2 = \lambda^8 + A \lambda^4 + 1$ established in our companion paper (arXiv:2604.09328), we give an unconditional proof of the perfect-cuboid conjecture ("Conโ€ฆ

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Mathematics Preprint PDF DOI

Hallucination, Abstention, and Recursive Inseparability

Takuma Imamura ยท 2026

The impossibility of eliminating hallucination, understood here as incorrect definite answers, in sufficiently expressive yes-or-no formal domains is an immediate consequence of classical undecidabiliโ€ฆ

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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

Freidlin-G\"artner formula and asymptotic profile in reaction-diffusion equations

Luca Rossi ยท 2026

We address the question of the large-time behavior of solutions to reaction-diffusion equations in periodic media. We start with the description of the asymptotic shape of the invasion set, which is cโ€ฆ

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Mathematics Preprint PDF DOI

Renormalized Solutions for a Class of Nonlinear Parabolic Equation with a Lower Order Term and Variable Exponents

Chunjin Li, Shijun Li, Shaopeng Xu ยท 2026

We consider a class of nonlinear parabolic equations \[ \dfrac{\partial}{\partial t} b(u)-\nabla \cdot (A(x,t,u,\nabla u))+H(x,t,\nabla u)=f , \] where $H$ is a nonlinear lower order term satiโ€ฆ

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Mathematics Preprint PDF DOI

Torus Equivariant Cohomology for the $\Delta$-Springer Fiber

Raymond Chou ยท 2026

We define a torus $U \subset T = (\mathbb{C}^\times)^K$ which acts on the $\Delta$-Springer varieties $Y_{n,\lambda,s}$ defined by Griffin-Levinson-Woo and give a Borel-style presentation for the equiโ€ฆ

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Mathematics Preprint PDF DOI

Existence and Uniqueness of Normalized Multi-peak Solutions for Coupled Nonlinear Schr\"odinger Systems

Wenhao Hu, Benniao Li, Wei Long, Chunhua Wang ยท 2026

We consider the following two-component coupled nonlinear Schr\"odinger (CNLS) system: \[ \begin{cases} -\Delta u +(P(x) + \lambda ) u=\mu_1 u^3+\beta u v^2, & \text{in } \mathbb{R}^N,\\ -\Delta v +(Qโ€ฆ

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Mathematics Preprint PDF DOI

A class of Exel--Laca algebras reciprocal to Cuntz--Krieger algebras

Kengo Matsumoto, Taro Sogabe ยท 2026

The reciprocality means a duality in Kirchberg algebras between K-theory groups and strong extension groups. In the paper, we will find a certain class of unital simple Exel--Laca algebras for which tโ€ฆ

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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

Reverse Tableaux and the Surjectivity of the Component Map in Type $A$

Yasmine Fittouhi ยท 2026

Let $G = \mathrm{SL}(n,\mathbb{C})$, let $B$ be a fixed Borel subgroup, and let $P \supset B$ be a parabolic subgroup determined by a composition $(c_1,\dots,c_k)$ of $n$. Write $P'$ for the derived gโ€ฆ

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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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On the existence and properties of Alexandroff paratopological groups

Pedro J. Chocano, Tayomara Borsich ยท 2026

We study groups endowed with Alexandroff topologies and show that no non-discrete Alexandroff topology can turn a group into a topological group. This settles negatively the basic existence problem foโ€ฆ

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Brane quantization and SYZ mirror symmetry

Kwokwai Chan, Naichung Conan Leung, Qin Li, Yat-Hin Suen, Yutung Yau ยท 2026

Coisotropic A-branes were introduced by Kapustin--Orlov to enlarge the Fukaya category of a symplectic manifold in a way that aligns with predictions from homological mirror symmetry. From a mathematiโ€ฆ

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The $p$-powers dividing certain exponential sums

Antonine Phigareau ยท 2026

We define the notion of couple density $(D, \mathbf b)$ where $D$ is a non-empty subset of $\mathbb Z^{m}$ and $ \mathbf b$ a fixed element in $\{0, \cdots, q-2\}^{m};$ We determine a minimum in termsโ€ฆ

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Metrics on triangulated categories and restrictions of (co)-$t$-structures

Wei Hu, Ziheng Liu ยท 2026

This paper explores the restriction behavior of silting-induced $t$-structures and co-$t$-structures on triangulated categories endowed with metrics. For compactly generated triangulated categories adโ€ฆ

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A PDE approach to Benamou--Brenier formula for the Schr\"odinger problem

Mattia Garatti, Luca Nenna, Simona Rota Nodari, Luca Tamanini ยท 2026

We studied the Benamou--Brenier formulation of the Schr\"odinger problem, focusing on a gap between theoretical results and applications, that often involve measures with unbounded support. While the โ€ฆ

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Sharp adaptive nonparametric testing for constant volatility

Johannes Brutsche, Lukas Riepl ยท 2026

Based on discrete observations, we develop a test to infer if the volatility function $\sigma(\cdot)$ within the nonparametric Gaussian white noise model $dY_t = \sigma(t)dW_t$ is constant. The testinโ€ฆ

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Sharp Strichartz estimate for the 1D periodic Schr\"odinger equation

Puti Dai, Zihua Guo ยท 2026

We prove the following estimate \[ \|{e^{it\partial_x^2}f}\|_{L_{(t,x)\in \mathbb{T}^2}^6}\leq C (\log N)^{{1/6}} \|f\|_{L^2_x(\mathbb{T})}, \] assuming $\mbox{supp} (\hat f)\subset [-N,N]$ for $N>1$.โ€ฆ

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Higher order Schr\"odinger operators

Federica Gregorio, Chiara Spina, Cristian Tacelli ยท 2026

In this paper we consider higher order Schr\"odinger operators $$\mathcal L u=Lu+Vu,$$ where $L$ denotes a fourth order operator and $V\geq 0$ a suitable potential. We initiate our analysis by consideโ€ฆ

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