International Journal of Theoretical Physics最新文献

{"title":"A Coordinate-free Approach to Obtaining Exact Solutions in General Relativity: The Newman-Unti-Tamburino Solution Revisited","authors":"Emir Baysazan,&nbsp;Ayşe Hümeyra Bilge,&nbsp;Tolga Birkandan,&nbsp;Tekin Dereli","doi":"10.1007/s10773-025-06228-7","DOIUrl":"10.1007/s10773-025-06228-7","url":null,"abstract":"<div><p>The Newman-Unti-Tamburino (NUT) solution is characterized as the unique Petrov Type <i>D</i> vacuum metric such that the two double principal null directions form an integrable distribution. The uniqueness of the NUT is established by evaluating the integrability conditions of the Newman-Penrose equations up to <span>(SL(2,mathbb {C}))</span> transformations, resulting in a coordinate-free characterization of the solution.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340253","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}

{"title":"Variational and Operator-Theoretic Analysis of Spectral Gaps in Yang–Mills Hamiltonians","authors":"Mehardeep Singh","doi":"10.1007/s10773-025-06168-2","DOIUrl":"10.1007/s10773-025-06168-2","url":null,"abstract":"<div><p>We present a constructive, gauge-invariant framework for non-Abelian Yang–Mills theory in four-dimensional Minkowski space, developed via an autonomous symbolic discovery engine called <span>NEXUS</span>. Starting from canonical quantization in the Weyl gauge, we synthesize a BRST-invariant Hamiltonian operator that preserves gauge symmetry, self-adjointness, and Osterwalder–Schrader reflection positivity. Through variational analysis on explicitly constructed trial functionals, we establish a non-zero lower bound between the vacuum and the first gauge-invariant excitation. This spectral gap aligns quantitatively with predictions from lattice QCD and supports the emergence of glueball-like excitations. The methodology integrates operator analysis, BRST cohomology, Euclidean reconstruction, and renormalization group stability, offering a formal framework for probing nonperturbative spectral structure in quantum gauge theories. Our approach highlights the potential of symbolic AI systems in deriving rigorous results within mathematical physics.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339810","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}

{"title":"Blocking Temperature Analysis in Two Distinct Lattice Topologies: Dice vs Lieb via Monte Carlo Simulations","authors":"Z. Fadil,&nbsp;Chaitany Jayprakash Raorane,&nbsp;Hussein. Sabbah,&nbsp;A. Jabar,&nbsp;Khaled H. Mahmoud,&nbsp;Abdulrahman A. Alsayyari,&nbsp;Seong-Cheol Kim","doi":"10.1007/s10773-026-06283-8","DOIUrl":"10.1007/s10773-026-06283-8","url":null,"abstract":"<div><p>Through Monte Carlo simulations based on the Blume-Emery-Griffiths model applied to dice and Lieb lattice configurations, this study investigated the influence of exchange interactions and the crystal field on the blocking temperature. The analysis emphasized the critical role of lattice geometry in determining magnetic stability and highlighted the sensitivity of the blocking temperature to variations in microscopic parameters. Furthermore, the emergence of complex magnetic behaviors under strong anisotropic fields underscored the intricate interplay between thermal fluctuations and spin interactions. These findings demonstrate that both the arrangement of the lattice and the nature of the underlying interactions are key factors in tailoring the magnetic properties of nanostructured materials.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340194","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}

{"title":"Impact of (Lambda )–Parametrization on Stellar Collapse and Spacetime Singularities","authors":"Anjali Pandey,&nbsp;Anurag Awasthi,&nbsp;Sudhir Kumar Srivastava","doi":"10.1007/s10773-026-06275-8","DOIUrl":"10.1007/s10773-026-06275-8","url":null,"abstract":"<div><p>The present work deals with the study of the gravitational collapsing phenomenon of spherically symmetric massive stars with a <span>(Lambda )</span> parametrization. A collapsing model with a cosmological constant of the form <span>(Lambda =beta left( frac{dot{Theta }}{3} + frac{Theta ^2}{9}right) )</span> has been considered. In this model, exact solutions of the Einstein field equations (EFEs) are obtained using the <span>(Lambda )</span> parametrization and the junction conditions. All the physical and geometrical quantities are calculated in terms of the Schwarzschild mass <i>M</i> and areal radius <i>R</i> of spherically symmetric stars. Consequently, we have approximated the masses and radii of different stars to estimate the value of the model parameter <span>(beta )</span>. We discuss the collapsing process and singularity formation for these stars and observe that all the physical and geometrical parameters of the model heavily depend on the model parameter <span>(beta )</span>. We further discuss spacetime singularity through the development of an apparent horizon.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339258","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}

{"title":"Strong Mechanical Squeezing and Entanglement in Modulated Cavity Magnomechanics","authors":"Ya-Ting Kang,&nbsp;Xi-Yao Ma,&nbsp;Jin-Liang Guo","doi":"10.1007/s10773-026-06282-9","DOIUrl":"10.1007/s10773-026-06282-9","url":null,"abstract":"<div><p>We study theoretically the achievement of strong mechanical squeezing and entanglement in a magnomechanical system consisting of a magnon mode and a mechanical mode, where the magnon mode is driven by a periodically modulated microwave field. By utilizing the self-cooling mechanism inherent in the cavity magnomechanics and combining it with the nonlinear effects induced by the periodic amplitude modulation, the steady-state mechanical squeezing and bipartite entanglement can be generated not only in the resolved sideband regime but also in the unresolved sideband regime. Interestingly, influenced by the periodic modulation, strong mechanical squeezing can be achieved in the resolved sideband regime. Moreover, both the mechanical squeezing and the entanglement exhibit strong robustness against the environmental temperature.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339249","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}

{"title":"Higher-order p-form Asymptotic Symmetries in (D=p+2)","authors":"Matteo Romoli,&nbsp;Federico Manzoni","doi":"10.1007/s10773-026-06276-7","DOIUrl":"10.1007/s10773-026-06276-7","url":null,"abstract":"<div><p>We investigate higher-order asymptotic symmetries for a <i>p</i>-form gauge field in <span>((p+2))</span>-dimensional Minkowski spacetime, where Hodge duality with a scalar holds. Employing symplectic renormalization, we identify <span>(N+1)</span> asymptotic charges, with each charge being parametrised by a function of the angular variables. By means of the Hodge decomposition, these charges share the same formal structure independently from <i>p</i> and are manifestly dual to a scalar charge. We work in Lorenz gauge, therefore the gauge parameters require a radial expansion involving logarithmic (subleading) terms to ensure nontrivial angular dependence at leading order. At the same time we assume a power expansion for the field strength, allowing logarithms in the gauge field expansions within pure gauge sectors. We compute the charge algebra, which turn out to be abelian up to possible central extension due to mixed electric/magnetic charge sector and/or unexploited ambiguities during symplectic renormalization.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339250","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}

{"title":"Abundant Soliton Solutions to the New Modified Spectral KdV Equation in Ocean Engineering with Bifurcation Analysis","authors":"Md Nur Hossain,&nbsp;I. Abouelfarag,&nbsp;Abdulkafi Mohammed Saeed,&nbsp;K. El-Rashidy,&nbsp;M. Mamun Miah,&nbsp;Wen-Xiu Ma","doi":"10.1007/s10773-025-06183-3","DOIUrl":"10.1007/s10773-025-06183-3","url":null,"abstract":"<div><p>The transformation of water waves in shallow regions is a complex phenomenon. As waves reach the beach, they undergo many processes, including shoaling, refraction, diffraction, and breaking. The importance of precisely forecasting wave patterns in shallow water areas is underscored by their influence on sediment transport, circulation, and other nearshore processes. This work looks at the one-dimensional modified spectral Korteweg–de Vries (mSKdV) equation as a mathematical framework to improve the comprehension of nonlinear wave transformation in shallow water. The research provides insights into the influence of changing bathymetry and nonlinearity on wave evolution along the beach. The unified method and the <span>(left(frac{{G}^{prime}}{G}, frac{1}{G}right))</span> method are two effective techniques that are utilized in order to derive soliton solutions for this equation. A bifurcation analysis is conducted to ascertain the phase portrait of this equation. Beyond the direct observations, a linear stability analysis was also performed. This crucial step further confirms and quantifies how the stability of our solutions changes across various bathymetries. This analysis provides a rigorous mathematical framework, reflecting the solutions' resilience and behavior under different underwater topographies. A synthesis of three-dimensional plots, modified two-dimensional plots concerning the time variable t, and density plots is employed to illustrate the precise solutions obtained. These diagrams illustrate the transition from the shallow water zone to the shoreline. Various soliton phenomena have been observed, including periodic solitons, bright and dark solitons, periodic breathers, quasi-breathers, breathers, and kinks. This discovery significantly advances the development of soliton solutions for the mSKdV equation. It also offers significant insights on the spectrum wave height and setup that unfold in coastal engineering, especially in regions with shallow seas.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339260","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}

{"title":"Mass Spectra of Charm-Strange Hadronic States in a Screened Potential Model","authors":"Sreelakshmi M,&nbsp;Akhilesh Ranjan","doi":"10.1007/s10773-025-06223-y","DOIUrl":"10.1007/s10773-025-06223-y","url":null,"abstract":"<div><p>In this work, the mass spectra of charm-strange hadrons are studied using a non-relativistic screened potential model. The four-body problem is reduced to two-body problem using the diquark-antidiquark approach. Mass and decay properties are studied and compared with available experimental and other theoretical studies. The Schrödinger equation is solved numerically with the help of the Mathematica package. Spin-dependent terms are also added to the potential perturbatively.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10773-025-06223-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Symmetry Analysis and Application of the Invariant Subspace Method to the (2+1)-dimensional Mixed Fractional Boiti-Leon-Manna-Pempinelli Equation","authors":"Yapeng Shi,&nbsp;Yuqiang Feng,&nbsp;Jicheng Yu","doi":"10.1007/s10773-025-06243-8","DOIUrl":"10.1007/s10773-025-06243-8","url":null,"abstract":"<div><p>In this paper, our focus is on the (2+1)-dimensional mixed fractional Boiti-Leon-Manna-Pempinelli equation (MFBLMPE), which incorporates a Riemann–Liouville time fractional derivative alongside an integer-order derivative in the y-direction. The model can be used to simulate the process of water propagation. The exact solutions to the MFBLMPE are constructed through the distinct application of Lie symmetry analysis and the invariant subspace method. Firstly, the Lie algebras admitted by the MFBLMPE are derived utilizing Lie symmetry analysis. Subsequently, a corresponding one-dimensional optimal system is established, followed by the execution of symmetry reduction. Furthermore, conservation laws are derived using the newly formulated Noether theorem. Ultimately, Matlab is employed to visualize the three-dimensional diagrams of certain obtained solutions.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339160","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}

{"title":"Exploration of Soliton Solutions and Multi-Solitonic forms for the Extended Estevez-Prada and the Generalized P-Type Equations in (3+1)-Dimensions using the Advanced Mathematical Method","authors":"Agam Dwivedi,&nbsp;Dinesh Khattar,&nbsp;Sachin Kumar","doi":"10.1007/s10773-026-06259-8","DOIUrl":"10.1007/s10773-026-06259-8","url":null,"abstract":"<div><p>This article extracts the newly developed soliton solutions of two higher-dimensional nonlinear partial differential equations (NLPDEs): the extended Estevez-Prada and the generalized P-type equations in (3+1)-dimensions. Both governing equations are Painlevé integrable and describe various complex dynamical phenomena in tsunami wave propagation, nonlinear dynamics, optical bullet dynamics in nonlinear fibers, and ion-acoustic soliton stability in magnetized plasmas. Using the extended Jacobian elliptic function expansion (EJEFE) method, we present novel families of closed-form solutions, with solitons, kinks, lumps, and their interaction structures in both equations. These solutions degenerate into trigonometric and hyperbolic functions once the modulus parameter approaches 0 and 1, respectively. Furthermore, we also analyze the dynamic structure of the solutions obtained, including solitons, lumps, kinks, and their interactions via 3D, contour, and 2D graphics. The results demonstrate the capability of the applied methods in obtaining solutions to higher-order NLPDEs and emphasize the need to explore the realms of computational mathematics and engineering further. This paper presents an original perspective on evolving multi-soliton, multi-lumps, and multi-peakon patterns by connecting plasma physics, theoretical physics, and nonlinear physical applications. These findings pave the path for future improvements in ocean waves and wave propagation, improving our understanding of complex systems.</p></div>","PeriodicalId":597,"journal":{"name":"International Journal of Theoretical Physics","volume":"65 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339161","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}