The European Physical Journal Plus最新文献

{"title":"Quasi-periodic breathers in a system of three coupled PT-symmetric nonlinear waveguides","authors":"Andrey A. Bocharov","doi":"10.1140/epjp/s13360-025-06075-9","DOIUrl":"10.1140/epjp/s13360-025-06075-9","url":null,"abstract":"<div><p>A PT-symmetric model of three unidirectional coupled waveguides with Kerr-type nonlinearity and balanced gain and loss in edge waveguides is considered. During evolution, quasi-periodic breathers of two types with zero background may form in such a system. The modulation period for temporary breather oscillations strongly depends on the initial parameters of the incident wave. One type of breathers can interact quasi-elastically with each other, acquiring small changes in the amplitudes and velocities of incoming waves after a collision. The model can be useful in creating purely optical processing devices, for example, as an analog-to-digital converter.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Study of compositional and luminescence properties of calcite in lapis lazuli for provenance investigations of archaeological findings","authors":"Marta Magalini,&nbsp;Laura Guidorzi,&nbsp;Alessandro Re,&nbsp;Miriana Marabotto,&nbsp;Alessandro Borghi,&nbsp;Paolo Gallo,&nbsp;Massimo Vidale,&nbsp;Leonardo La Torre,&nbsp;Matteo Campostrini,&nbsp;Quentin Lemasson,&nbsp;Laurent Pichon,&nbsp;Brice Moignard,&nbsp;Claire Pacheco,&nbsp;Pierre Couture,&nbsp;Vladimir Palitsin,&nbsp;Alessandro Lo Giudice","doi":"10.1140/epjp/s13360-025-06095-5","DOIUrl":"10.1140/epjp/s13360-025-06095-5","url":null,"abstract":"<div><p>In this study, calcite crystals within 42 lapis lazuli reference rocks coming from four distinct mining regions (in present-day Afghanistan, Tajikistan, Siberia and Myanmar) were characterised in terms of their compositional and luminescence properties in order to identify potential provenance markers. A non-destructive approach based on Ion Beam Analysis was employed, in particular using μ-Particle Induced X-rays Emission (μ-PIXE) and μ-Ion Beam Induced Luminescence (μ-IBIL). The results indicate that calcite crystals in Afghan rocks are characterised by the highest quantity of Mg and Mn; whereas, Siberian calcite exhibit the highest Sr content. The application of Principal Component Analysis also enhanced the possibility of discriminating between the Myanmar and Tajik rocks, as well as between the four provenances in general, by exploiting the compositional variability of Mg, Mn, Sr and Y elements. Regarding the luminescence properties, notable differences in the intensity ratio between the 360 nm and the 620 nm luminescence bands were detected among the provenances. In the second part of this study, the new results were employed to infer the origin of the raw material of certain archaeological findings discovered in two different historical sites: four lapis lazuli fragments from Shahr-i Sokhta (Iran, 3rd millennium BCE) and a lapis lazuli tessera from the city of Tanis (Egypt, 1050–700 BCE). The results of the analysis indicate that, among the four provenances considered in the reference rocks database, the best compatibility of the data from both case studies is found with the Afghan dataset. This suggests that the area of Afghanistan is the most probable source for the raw materials of the investigated findings.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06095-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Gravitationally induced uncertainty relation, quantum coherence and complete complementarity relation","authors":"Duo-Duo Chen,&nbsp;Dong-Dong Dong,&nbsp;Xue-Ke Song,&nbsp;Liu Ye,&nbsp;Dong Wang","doi":"10.1140/epjp/s13360-025-06094-6","DOIUrl":"10.1140/epjp/s13360-025-06094-6","url":null,"abstract":"<div><p>Gravity quantization is regarded as a great challenge and being of fundamental importance in the modern physics. Recently, it has been found that entanglement induced by gravity can be generated in interferometric setups which may be used to examine the quantumness of gravity. In addition to entanglement, there are various diverse resources to manifest the quantumness of gravity. Herein, we investigate gravitationally induced uncertainty, coherence and complete complementarity relation (CCR) between two masses. The result shows that the gravitationally induced entropy-based uncertainty is highly insensitive to the reflectivity of beam splitter (BS). Importantly, we suggest the uncertainty relation can be used to entanglement witness in the current framework. Besides, we reveal that the relative entropy of coherence can approach to maximum in certain reflectivity of BS. Furthermore, the von Neumann entropy-based CCR is proved under quantum gravity, offering a powerful means for characterizing quantum correlations in bipartite systems. Thereby, we argue the current investigation offers insight into quantumness of gravity, and helps us better understand quantum gravity.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Next-next-nearest neighbor hopping effects on the MI and on the dynamics of breathers in 2D quantum ultracold atoms loaded in optical lattices","authors":"Z. I. Djoufack,&nbsp;J. P. Nguenang,&nbsp;A. Kenfack-Jiotsa","doi":"10.1140/epjp/s13360-025-06124-3","DOIUrl":"10.1140/epjp/s13360-025-06124-3","url":null,"abstract":"<div><p>We explore analytically and numerically the dual role played by the next-next-nearest neighbor (NNNN) hopping coupling on the modulation instability (MI) and on the dynamics of breathers in 2D quantum ultracold atoms loaded in optical lattices. Via the linear stability analysis, it is shown that the dispersion relation formed exhibits intriguing forms. It is found that the emergence of MI regions and the growth rate may be significantly affected by the NNNN hopping coupling strength. To support the analytical studies, direct numerical simulations of MI are carried out to show the generation of a train of short waves exhibiting periodic W-shaped and V-shaped solitons with decreasing amplitude as time evolves. The appearance of breathers in the regions where the MI manifests is predicted to be influenced by the NNNN hopping coupling strength. By making use of Rayleigh-Ritz variational approach and in agreement with the MI analysis, the analytical results reveal the existence of the radial modes and discrete vortex solitons in called this framework, the dynamics of breathers. The accuracy of the outcomes is checked by numerical calculations which show a good agreement with the theoretical analysis.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Energy-time uncertainty relation from entropy measures","authors":"Nana Cabo Bizet,&nbsp;Octavio Obregón,&nbsp;Wilfredo Yupanqui Carpio","doi":"10.1140/epjp/s13360-025-06126-1","DOIUrl":"10.1140/epjp/s13360-025-06126-1","url":null,"abstract":"<div><p>In a previous study, it was shown that the generalized uncertainty principle can be derived from non-extensive entropies, particularly those depending only on the probability, denoted as <span>(S_pm)</span> in the literature. This finding reveals an intriguing connection between non-extensive statistics and quantum gravity. In the present work, we extend our previous result and derive a generalized energy-time uncertainty relation based on a measure of non-extensive entropies. Consequently, the dispersion relation undergoes modifications consistent with those obtained in other approaches to quantum gravity. We interpret these modifications as evidence of the non-extensive behavior of spacetime fluctuations at scales close to the Planck scale. While these effects are significant in this regime, they become negligible in the classical one, i.e., at low energies where the spacetime is smooth. As a consequence of the non-extensive behavior exhibited by spacetime at very small scales, the black hole radiation temperature undergoes quantum-level corrections, increasing in the case of <span>(S_{-})</span> and decreasing for the case of <span>(S_{+})</span>. Moreover, the modified uncertainty relation derived here predicts a maximum uncertainty in energy, of the order of Planck energy, and a minimum time interval, of the order of the Planck time, offering new insights into the fundamental structure of spacetime in the quantum regime.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Effects of external gravitational field on highly rarefied gases: analysis based on stochastic soft-sphere collision models","authors":"Satori Tsuzuki","doi":"10.1140/epjp/s13360-025-06122-5","DOIUrl":"10.1140/epjp/s13360-025-06122-5","url":null,"abstract":"<div><p>This study examines the effects of an external gravitational field on highly rarefied gases in the transitional-flow regime near the free-molecular-flow regime. In our theoretical study, we rederive the classical kinetic theory for an ideal gas in terms of the kinetics of the constituent particles to account for the effect of particle acceleration by an external gravitational field. Subsequently, we derive an extended expression for the virial pressure equation as a generic description of the dynamics under an external gravitational field. We employ the soft-sphere model for the following reasons: In highly rarefied gases, short-range and instantaneous collisional interactions are dominant. Thus, by expanding the asymmetric two-body potential in the virial pressure equation and retaining only the contribution of the short-range interaction, we can obtain a soft-sphere model that represents the interaction in the collision direction as a harmonic oscillation. In the absence of dissipation, the soft-sphere model has been confirmed to reproduce fully elastic collisions. In our collision simulations, we define two parameters. The first parameter represents the collision probability between each pair of approaching particles, and the second represents the ratio of the magnitude of the external potential energy to the total kinetic energy of the particles. The behavior of the system is analyzed by varying the values of these two parameters. Our analysis shows that if the external potential energy is sufficiently small (1%–5%) compared with the total kinetic energy, then a pressure difference emerges between the walls. However, the system retains the properties of equilibrium statistical mechanics, as indicated by the Maxwell–Boltzmann (MB) distribution. In conclusion, highly rarefied gases obey the MB distribution even when placed under weak gravitational fields.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06122-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Stability, sensitivity, and bifurcation analysis of a fractional-order HIV model of CD(4^+) T cells with memory and external virus transmission from macrophages","authors":"Purnendu Sardar,&nbsp;Santosh Biswas,&nbsp;Krishna Pada Das,&nbsp;Saroj Kumar Sahani,&nbsp;Vikas Gupta","doi":"10.1140/epjp/s13360-025-06081-x","DOIUrl":"10.1140/epjp/s13360-025-06081-x","url":null,"abstract":"<div><p>This paper presents a fractional-order mathematical model in the Caputo sense to study the dynamics of HIV infection, focusing on the interactions among uninfected T cells, infected T cells, and HIV. The inclusion of fractional derivatives allows for the incorporation of memory effects, providing a more accurate representation of disease progression. We begin by establishing fundamental mathematical properties such as existence and uniqueness, positivity and boundedness of the solutions. The Caputo fractional derivative: Equilibrium points of the system are identified, and the basic reproduction number, <span>(mathcal {R}_0)</span>, is calculated to assess the potential for infection spread. Sensitivity analysis of <span>(mathcal {R}_0)</span> is performed to determine the most influential parameters, both positively and negatively. The local and global stability analyses have been carried out for all equilibrium points. We also derive the transcritical and Hopf bifurcation conditions, revealing the onset of oscillatory behavior. Numerical simulations are carried out using the fractional forward Euler method, demonstrating how the fractional-order <span>(alpha )</span> significantly influences the disease dynamics. Our results indicate that higher values of <span>(alpha )</span> are associated with oscillatory dynamics. In contrast, a reduction in <span>(alpha )</span> contributes to the stabilization of the system, as evidenced by the bifurcation diagrams for various fractional orders. Additionally, we provide biological interpretations of all numerical results and compare every result with existing related models to highlight its novelty and relevance. The paper concludes with a summary of findings and potential future research directions.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Anisotropic quark stars in the modified f(Q, T) gravity: an application of the MIT bag model","authors":"H. Rizwana Kausar,&nbsp;Amal Majid,&nbsp;Bismah Nadeem","doi":"10.1140/epjp/s13360-025-06102-9","DOIUrl":"10.1140/epjp/s13360-025-06102-9","url":null,"abstract":"<div><p>In this paper, we consider spherically symmetric static space-time and anisotropic fluid to investigate the solutions of the strange quark stars in the modified <i>f</i>(<i>Q</i>, <i>T</i>) theory of gravity. We use Heintzmann metric components to find the solution of <i>f</i>(<i>Q</i>, <i>T</i>) field equations for two different models with linear and nonlinear terms, respectively. To investigate the structural formation of the quark stars, we present strange quark matter in the form of MIT bag model. We consider PSR J1614-2230 as a candidate star to specify the mass and radius of the developed quark star models and study their characteristics for different values of the involved parameters. Also, by adopting different values of the free parameters, we find values of the bag constant and use them to check the energy density and anisotropic pressure of the obtained strange star models. We also calculate the energy conditions, stability conditions and the different state parameters, such as compactness factor, matter distribution, gravitational redshift, adiabatic index and energy conditions, for both the linear and nonlinear models. We draw graphs for all the calculated parameters and provide their analysis.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Author Correction: Effective strategies toward controlling tuberculosis: optimal control and cost-effectiveness analysis","authors":"Pooja Khoda,&nbsp;Vijay Pal Bajiya,&nbsp;Sada Nand Prasad","doi":"10.1140/epjp/s13360-025-06132-3","DOIUrl":"10.1140/epjp/s13360-025-06132-3","url":null,"abstract":"","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Dosimetric analysis of true beam linear accelerators and assessment of dosimetry of photon beams for various treatment parameters","authors":"Roya Feroze,&nbsp;Hannan Younis,&nbsp;Mohammad Ayaz Ahmad,&nbsp;M. Adil Khan,&nbsp;Saeed Ur Rehman,&nbsp;Shawn Jagnandan,&nbsp;Antalov Jagnandan,&nbsp;Mavia Anjum,&nbsp;Noor Ul Huda Abbasi,&nbsp;Esam M. Al-Shaebi,&nbsp;Muhammad Ajaz","doi":"10.1140/epjp/s13360-025-06091-9","DOIUrl":"10.1140/epjp/s13360-025-06091-9","url":null,"abstract":"<div><p>The True beam linear accelerator is a state-of-the-art device widely used in cancer treatment for its ability to deliver flattening-filter-free (FFF) and flattened photon beams. Despite its clinical significance, detailed information on its dosimetric characteristics remains limited. This study systematically evaluated dosimetric parameters for photon beam energies of 6 MV, 6 MV FFF, and 15 MV using high-resolution diode detectors and ion chambers. Measurements were conducted at a source-to-surface distance of 100 cm for field sizes ranging from 10 × 10 cm² to 40 × 40 cm² and depths of <i>D</i>_max, 5 cm, 10 cm, 20 cm, and 30 cm in water. Key metrics, including percentage depth doses (PDDs) and beam profiles, were analyzed to assess the effect of beam energy, field size, and depth on dosimetry. Comparisons of measured data from NORI Cancer Hospital and Shaukat Khanum Memorial Hospital demonstrated consistent and accurate performance across systems. These findings provide valuable insights into the dosimetric behavior of TrueBeam accelerators, contributing to the optimization of treatment protocols and ensuring improved patient outcomes.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}