Pramana最新文献_第3页

Embeddings with generalised Vaidya spacetime 广义Vaidya时空嵌入

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-08-03 DOI: 10.1007/s12043-026-03166-9

Ayanda Kunyana, Noeleen Naidoo, Sunil D. Maharaj, Rituparno Goswami

引用次数: 0

Exploring dark energy via non-minimal coupling in ({varvec{f}}({varvec{Q,L}}_{{varvec{m}}})) gravity with Gong-Zhang parametrization 利用Gong-Zhang参数化通过({varvec{f}}({varvec{Q,L}}_{{varvec{m}}}))引力非极小耦合探索暗能量

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-21 DOI: 10.1007/s12043-026-03152-1

Yash B. Ingole, K. V. Somwanshi, S. N. Bayaskar

{"title":"Exploring dark energy via non-minimal coupling in ({varvec{f}}({varvec{Q,L}}_{{varvec{m}}})) gravity with Gong-Zhang parametrization","authors":"Yash B. Ingole, K. V. Somwanshi, S. N. Bayaskar","doi":"10.1007/s12043-026-03152-1","DOIUrl":"10.1007/s12043-026-03152-1","url":null,"abstract":"<div>In this study, we investigate the late-time accelerated expansion of the universe within the framework of non-minimally coupled (f(Q, L_m)) gravity, where Q is the non-metricity scalar and (L_m) is the matter Lagrangian. We derive modified Friedmann equations in a flat Friedmann–Lemaître–Robertson–Walker (FLRW) metric background and employ the Gong-Zhang equation of state (EoS) parametrization, allowing an analytical form of the Hubble parameter (H!(z)). The model parameters are constrained using recent cosmic chronometers (CC) and Pantheon+SH0ES Type Ia supernova datasets through Markov Chain Monte Carlo (MCMC)-based chi-squared minimization. We analyze various cosmological quantities, including the deceleration parameter, EoS parameter, jerk, snap, lerk, and diagnostic tools such as Om(z) and the statefinder pair (r, s). Our findings indicate a viable transition from deceleration to acceleration and reveal a quintessence-like evolution of dark energy (DE). Furthermore, energy conditions are tested, showing a violation of the strong energy condition, consistent with current cosmic acceleration. The results establish that the (f(Q, L_m)) framework with non-minimal coupling and a parametrized EoS provides a compelling alternative to (Lambda )CDM in describing cosmic acceleration.</div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"100 3","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study of the one-dimensional Schrödinger equation for a particle with position-dependent mass: Application of a Hulthén-type mass distribution and a Morse potential 具有位置依赖质量的粒子的一维Schrödinger方程的研究：hulthsamn -type质量分布和Morse势的应用

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-21 DOI: 10.1007/s12043-026-03161-0

S. Medjenah, F. Benamira

引用次数: 0

Investigation of Jacobi function solutions of the fractional Benjamin–Ono equation 分数阶Benjamin-Ono方程Jacobi函数解的研究

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-21 DOI: 10.1007/s12043-026-03156-x

Gamze Kiratli, Mutlu Akar

引用次数: 0

Non-Newtonian hydromagnetic nanofluid flow past an inclined conical disk system 非牛顿流体磁纳米流体流过倾斜锥形圆盘系统

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-21 DOI: 10.1007/s12043-026-03146-z

JYOTI PRAKASH SHARMA, RAKESH KUMAR, PARAS RAM, KUPPALAPALLE VAJRAVELU

{"title":"Non-Newtonian hydromagnetic nanofluid flow past an inclined conical disk system","authors":"JYOTI PRAKASH SHARMA, RAKESH KUMAR, PARAS RAM, KUPPALAPALLE VAJRAVELU","doi":"10.1007/s12043-026-03146-z","DOIUrl":"10.1007/s12043-026-03146-z","url":null,"abstract":"<div>Conical disk systems play a crucial role in biomedical engineering, rheometer, viscometry, and advanced thermal devices due to their ability to regulate flow and transport processes. In this study, we investigate the nonlinear behavior of tangent hyperbolic nanofluid flow across an inclined conical disk configuration, which uniquely combines a stretchable disk with a rotatable cone under the influence of magnetohydrodynamic (MHD) effects. By employing similarity transformations, the governing nonlinear partial differential equations are reduced to a system of dimensionless ordinary differential equations, which are then solved numerically using MATLAB’s boundary value solver bvp5c. To further improve computational efficiency and predictive capability, a feed-forward backpropagation neural network is trained on the numerical results for heat and mass transfer rates. The results demonstrate that increasing the disk inclination angle intensifies radial flow, while simultaneously reducing thermal and solutal transfer rates by 34.47% and 13.12%, respectively. Moreover, thermal transfer is found to be convection-dominated on the conical surface, whereas conduction governs the disk surface.These findings provide new insights into the nonlinear MHD transport characteristics of tangent hyperbolic nanofluids and highlight the potential of the proposed configuration for optimizing flow and energy transfer in biomedical devices, conical diffusers, and thermal management systems.</div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"100 3","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Lyapunov direct control of a quartic nonlinearity-based Sprott-I system 基于四次非线性的sport - i系统的Lyapunov直接控制

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-16 DOI: 10.1007/s12043-026-03150-3

A. I. Egunjobi, A. O. Adelakun, K. S. Ojo, K. D. Ajayi

引用次数: 0

On Lie symmetries, invariant solutions, conservation laws and soliton dynamics of Nizhnik–Novikov–Veselov equation in oceanic shallow-water 海洋浅水Nizhnik-Novikov-Veselov方程的Lie对称性、不变解、守恒定律和孤子动力学

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-16 DOI: 10.1007/s12043-026-03148-x

Dig Vijay Tanwar

{"title":"On Lie symmetries, invariant solutions, conservation laws and soliton dynamics of Nizhnik–Novikov–Veselov equation in oceanic shallow-water","authors":"Dig Vijay Tanwar","doi":"10.1007/s12043-026-03148-x","DOIUrl":"10.1007/s12043-026-03148-x","url":null,"abstract":"<div>The interaction of nonlinear waves in an inhomogeneous medium generally leads to temporal evolution in velocity, shape, or amplitude. Therefore, the study of solitary waves is prominent for re-emerging feature to its permanent structure after interaction. This work addresses the propagation dynamics of solitary waves for the NNV equation. It is a highly nonlinear two dimensional isotropic Lax integrable generalization of the well-known KdV equation. The symmetry reductions under infinitesimals and the generalized exact solutions of the NNV equation have been well investigated using the Lie symmetry method. The infinitesimals under a one-parameter group of transformations preserve invariance of the test equation and yield symmetry reductions. The twice implementation of symmetry reductions results in a system of ODEs. This system of ODEs is integrated under parametric constraints and provides exact solutions. These solutions are entirely new and more general than previously reported results, owing to arbitrary functions (f_1(t)), (f_2(t)), and (f_3(t)), as well as several constants. The generalness of derived results are ensured with deductions of previous results [8, 10,11,12]. To understand the propagation properties of wave phenomena, these solutions are extended to include a graphical representation, which reveals a novel class of solitons and lump solutions. Moreover, adjoint equations and conserved vectors are derived under the Lagrangian formulation using Ibragimov’s method for each generator.</div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"100 3","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neutron shell effects and decay mode competition in (mathbf {^{238text {--}338}{{textbf {H}}s}}) isotopes (mathbf {^{238text {--}338}{{textbf {H}}s}})同位素的中子壳效应和衰变模式竞争

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-16 DOI: 10.1007/s12043-026-03151-2

G. Tripathy, P. Mohanty, A. Anupam, C. Dash, B. B. Sahu

{"title":"Neutron shell effects and decay mode competition in (mathbf {^{238text {--}338}{{textbf {H}}s}}) isotopes","authors":"G. Tripathy, P. Mohanty, A. Anupam, C. Dash, B. B. Sahu","doi":"10.1007/s12043-026-03151-2","DOIUrl":"10.1007/s12043-026-03151-2","url":null,"abstract":"<div>We study the shell closure, alpha-decay and cluster-decay ((^{8})Be, (^{12})C, (^{14})C, (^{16})O) of even-even (^{238text {--}338}textrm{Hs}_{108}) isotopes using relativistic mean field (RMF) model within an axially deformed oscillator basis with two force parameter sets like NL3* and NL-SH. In this article, the bulk properties such as binding energy (BE), rms charge radius, quadrupole deformation, neutron skin thickness, three neutron pairing gap for charge radius, two neutron separation energies ((S_{2n})), differential variation of two neutron separation energy ((dS_{2n})) and neutron pairing gap using three-, four- and five-point formulae have also been investigated thoroughly for the above mentioned isotopic series. Half-life periods are determined using the Viola-Seaberg, Royer, MUDL, UDL-1, UDL-2, Santosh et al. and unified formula by Ni et al. using calculated and experimentally accessible Q-values. For the prediction of the favorable decay mode of the isotopic series, the spontaneous fission half-life is also calculated by using two different formulas that are independent of force parameters. All the outcomes are compared with available experimental data. We found (^{270})Hs is a comparably stable isotope of Hs with other possible shell closures at ({N} =138), 142, 154, 162, 166, 182, 184, 186, 210, 220, 222. This study helps us to understand the shell and subshell closures of even-even Hassium isotopes and their preferred decay modes.</div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"100 3","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on the Lax integrability of the (3 + 1)-dimensional BKP-Boussinesq equation （3 + 1）维BKP-Boussinesq方程的Lax可积性研究

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-09 DOI: 10.1007/s12043-026-03131-6

Yingjun Bao, Taogetusang Bao

引用次数: 0

Generalized approach to applications of quantum time-dependent harmonic oscillator model with variable mass and frequency via dynamical invariant formalism 基于动态不变形式论的变质量变频率量子时变谐振子模型的推广应用

IF 2.3 4区物理与天体物理

Pramana Pub Date : 2026-07-06 DOI: 10.1007/s12043-026-03155-y

Metin Aktas, Biswanath Rath, Ramazan Sever

引用次数: 0