Afrika Matematika最新文献

Oscillatory integral characterizations of uniform exponential dichotomy for periodic evolution families 周期演化族一致指数二分法的振荡积分表征

IF 0.8

Afrika Matematika Pub Date : 2026-10-24 DOI: 10.1007/s13370-026-01518-7

Dhaou Lassoued

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引用次数: 0

On relatively Fredholm perturbations and the stability of (textrm{M})-essential spectra associated with the sum of (2times 2) block operator matrices 与(2times 2)块算子矩阵和相关的(textrm{M}) -本质谱的相对Fredholm摄动和稳定性

IF 0.8

Afrika Matematika Pub Date : 2026-10-14 DOI: 10.1007/s13370-026-01515-w

Sana Bouzidi

引用次数: 0

A reduction principle for Ishikawa convergence of common best proximity points 公共最佳邻近点石川收敛的约简原理

IF 0.8

Afrika Matematika Pub Date : 2026-09-30 DOI: 10.1007/s13370-026-01514-x

Moosa Gabeleh

引用次数: 0

Correction: Hyperstability of a quartic functional equation in complete quasi-2-normed space 修正：完全拟2赋范空间中一个四次泛函方程的超稳定性

IF 0.8

Afrika Matematika Pub Date : 2026-09-17 DOI: 10.1007/s13370-026-01513-y

Ravinder Kumar Sharma, Meenu Prajapati, Ashish Kumar Rawat, Sumit Chandok

引用次数: 0

Extending the Schrödinger–Lichnerowicz formula to fractional Dirac operators on Riemannian manifolds 将Schrödinger-Lichnerowicz公式推广到黎曼流形上的分数狄拉克算子

IF 0.8

Afrika Matematika Pub Date : 2026-09-02 DOI: 10.1007/s13370-026-01467-1

Rami Ahmad El-Nabulsi, Waranont Anukool

{"title":"Extending the Schrödinger–Lichnerowicz formula to fractional Dirac operators on Riemannian manifolds","authors":"Rami Ahmad El-Nabulsi, Waranont Anukool","doi":"10.1007/s13370-026-01467-1","DOIUrl":"10.1007/s13370-026-01467-1","url":null,"abstract":"<div><p>In this work, we introduce a generalized class of fractional Dirac operators constructed through the Whittaker transform of the Mittag–Leffler function using the generalized Fox–Wright function. The framework extends the theory of Dirac operators to the fractional setting on Riemannian manifolds via Clifford algebras, spin representations, and the geometry of fiber bundles. Fundamental properties of these operators are established, showing that they combine conventional and fractional derivatives, thereby generalizing key results in Riemannian geometry. In particular, we extend the Schrödinger–Lichnerowicz formula to fractional order, revealing new scalar curvature terms governed by different fractional derivatives. This approach bridges fractional calculus and geometric analysis, offering potential applications in field theory and the study of manifolds with fractal dimensions. Furthermore, we analyze the fractional Dirac operator on Lorentzian cylinders under Atiyah–Patodi–Singer boundary conditions, deriving corresponding constraints on the fractional exponents. The formulation naturally leads to a fractional Schrödinger–Dirac equation encompassing higher-order derivative terms. Our findings open prospects for extending the fractional formalism to spectral geometry and noncommutative spaces, particularly through the development of a fractional spectral action principle, where the geometric action is constructed from the spectrum of a fractional Dirac operator, and the investigation of index theorems and algebraic geometric structures associated with fractional Dirac operators, which generalize the classical Dirac operator by incorporating fractional-order nonlocal effects.</p></div>","PeriodicalId":46107,"journal":{"name":"Afrika Matematika","volume":"37 3","pages":""},"PeriodicalIF":0.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Left-definite theory for dynamic Sturm–Liouville problems 动态Sturm-Liouville问题的左定理论

IF 0.8

Afrika Matematika Pub Date : 2026-08-28 DOI: 10.1007/s13370-026-01502-1

Bilender P. Allahverdiev, Hüseyin Tuna, Hatice Bulut Demiralay

引用次数: 0

(phi (pq))-evaluation algorithm: a novel approach for an efficient retrieval of Euler’s totient of an RSA modulus (phi (pq))-评估算法：一种新的方法，为一个有效的检索欧拉的RSA模量

IF 0.8

Afrika Matematika Pub Date : 2026-08-21 DOI: 10.1007/s13370-026-01500-3

Jay Mehta, Hitarth Rana

引用次数: 0

Low separation axioms in primal spaces and the Zariski Topology 原始空间中的低分离公理与Zariski拓扑