物理最新文献

{"title":"Microstructure response of concentrated suspensions to flow reversal.","authors":"A A García, Y L Roht, I Ippolito, D Salin, G Drazer, J P Hulin, G Gauthier","doi":"10.1140/epje/s10189-025-00472-9","DOIUrl":"https://doi.org/10.1140/epje/s10189-025-00472-9","url":null,"abstract":"<p><p>We study experimentally at the macroscopic and microstructure scale a dense suspension of non-Brownian neutrally buoyant spherical particles experiencing periodic reversals of flow at constant rate between parallel plates and tracked individually. We first characterize the quasi-steady state reached at the end of half periods. The volume fraction of particles increases from the walls to the center as a result of migration induced by the nonuniform strain rate. Except very close to the walls and the center, the particle pair distribution is fore-aft asymmetric with depletions of pairs in the extensional quadrants, similar to that reported for shear flows of same volume fraction as the local one. The dynamics of the periodic rearrangements occurring after each flow reversal are characterized by a microstructure tensor component. The relaxation time characterizing the reorganization increases from the walls to the center due to the inhomogeneous strain rate. On the other hand, the local accumulated strain required for this reorganization decreases with the volume fraction, like for viscosity measurements in uniform strain rate conditions. However, the variation of the microstructure with the accumulated strain is faster than that of the viscosity, showing the complementarity of the two measurements.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 1","pages":"7"},"PeriodicalIF":1.8,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143027667","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":"Elucidating the impact of laser shock peening on the biocompatibility and corrosion behaviour of wire arc additive manufactured SS316L bone staples","authors":"Geethapriyan Thangamani,&nbsp;Santosh Kumar Tamang,&nbsp;Jhasketan Badhai,&nbsp;Sibi Karthik,&nbsp;Jinoop Arackal Narayanan,&nbsp;Muthuramalingam Thangaraj,&nbsp;Arunkumar Thirugnanasambandam,&nbsp;Avinash Sonawane,&nbsp;Palani Iyamperumal Anand","doi":"10.1007/s00339-025-08261-z","DOIUrl":"10.1007/s00339-025-08261-z","url":null,"abstract":"<div><p>This study investigates the impact of Laser Shock Peening (LSP) on the biocompatibility and corrosion resistance of SS316L bone staples built using Wire Arc Additive Manufacturing (WAAM). Corrosion tests reveal substantial improvements, with a decrease in corrosion current density from 32.137 × 10^− 4 mA/cm² to 3.50864 × 10^− 4 mA/cm², a reduction in corrosion rate from 3.66754 × 10^− 2 mm/year to 0.400415 × 10^− 2 mm/year. Surface hydrophobicity evaluated through contact angle measurements, demonstrates an increase to 98.85° at the highest LSP intensity of 15.0 GW/cm², indicating improved surface properties critical for biomedical applications. The cytotoxicity analysis and surface morphology indicate that the survival, morphology, and adherence of L929 fibroblast cells improve with increasing LSP intensity.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 2","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fermionic steering in multi-event horizon spacetime","authors":"Shu-Min Wu,&nbsp;Jin-Xuan Li,&nbsp;Yu-Xuan Wang,&nbsp;Si-Han Shang,&nbsp;Jianbo Lu","doi":"10.1140/epjc/s10052-025-13774-1","DOIUrl":"10.1140/epjc/s10052-025-13774-1","url":null,"abstract":"<div><p>We investigate quantum steering of Dirac field for different types of Bell states in Schwarzschild–de Sitter (SdS) spacetime that has a black hole event horizon (BEH) and a cosmological event horizon (CEH). We find that fermionic steerability from Bob to Alice is greater than fermionic steerability from Alice to Bob, while bosonic steerability exhibits the opposite behavior in SdS spacetime. These different properties between fermionic and bosonic steering arise from the differences between Fermi–Dirac statistics and Bose–Einstein statistics. We also find that the Hawking effect of the black hole decreases fermionic steerability. However, the Hawking effect of the expanding universe can enhance fermionic steerability, which differs from the properties of quantum steering in single-event horizon spacetime. Interestingly, we can indirectly protect quantum steering by using appropriate types of Bell states in multi-event horizon spacetime. These conclusions are helpful to guide the task of processing relativistic quantum information for quantum steering in SdS spacetime.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13774-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions","authors":"Reggie C. Pantig","doi":"10.1140/epjc/s10052-025-13766-1","DOIUrl":"10.1140/epjc/s10052-025-13766-1","url":null,"abstract":"<div><p>In this paper, an analytic generalization of the weak field deflection angle (WDA) is derived by utilizing the current non-asymptotically flat generalization of the Gauss–Bonnet theorem. The derived formula is valid for any Schwarzschild-like spacetime, which deviates from the classical Schwarzschild case through some constant parameters. This work provided four examples, including Schwarzschild-like solutions in the context of Bumblebee gravity theory and the Kalb–Ramond framework, as well as one example from a black hole surrounded by soliton dark matter. These examples explore distinct mechanisms of Lorentz symmetry breaking, with results that are either new or in agreement with existing literature. The WDA formula provided a simple calculation, where approximations based on some conditions can be done directly on it, skipping the preliminary steps. For the shadow size analysis, it is shown how it depends solely on the parameter associated with the metric coefficient in the time coordinate. A general formula for the constrained parameter is also derived based on the Event Horizon Collaboration (EHT) observational results. Finally, the work realized further possible generalizations on other black hole models, such as RN-like, dS/AdS-like black hole solutions, and even black hole solutions in higher dimensions.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13766-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Deep learning-based superconductivity prediction and experimental tests","authors":"Daniel Kaplan,&nbsp;Adam Zheng,&nbsp;Joanna Blawat,&nbsp;Rongying Jin,&nbsp;Robert J. Cava,&nbsp;Viktor Oudovenko,&nbsp;Gabriel Kotliar,&nbsp;Anirvan M. Sengupta,&nbsp;Weiwei Xie","doi":"10.1140/epjp/s13360-024-05947-w","DOIUrl":"10.1140/epjp/s13360-024-05947-w","url":null,"abstract":"<div><p>The discovery of novel superconducting materials is a long-standing challenge in materials science, with a wealth of potential for applications in energy, transportation and computing. Recent advances in artificial intelligence (AI) have enabled expediting the search for new materials by efficiently utilizing vast materials databases. In this study, we developed an approach based on deep learning (DL) to predict new superconducting materials. We have synthesized a compound derived from our DL network and confirmed its superconducting properties in agreement with our prediction. Our approach is also compared to previous work based on random forests (RFs). In particular, RFs require knowledge of the chemical properties of the compound, while our neural net inputs depend solely on the chemical composition. With the help of hints from our network, we discover a new ternary compound Mo₂₀Re₆Si₄, which becomes superconducting below 5.4 K. We further discuss the existing limitations and challenges associated with using AI to predict and, along with potential future research directions.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-024-05947-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995358","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":"Micro-computed tomography and laser micro-ablation on altered pyrite in lapis lazuli to enhance provenance investigation: a new methodology and its application to archaeological cases","authors":"Marta Magalini,&nbsp;Laura Guidorzi,&nbsp;Alessandro Re,&nbsp;Francesca Tansella,&nbsp;Federico Picollo,&nbsp;Sofia Sturari,&nbsp;Pietro Aprà,&nbsp;Georgina Herrmann,&nbsp;Randall Law,&nbsp;Quentin Lemasson,&nbsp;Laurent Pichon,&nbsp;Brice Moignard,&nbsp;Claire Pacheco,&nbsp;Alessandro Lo Giudice","doi":"10.1140/epjp/s13360-025-05988-9","DOIUrl":"10.1140/epjp/s13360-025-05988-9","url":null,"abstract":"<div><p>This work presents an upgrade to the methodology adopted to investigate the provenance of the raw lapis lazuli material used in antiquity for carving precious artefacts. Samples from archaeological excavation contexts frequently display superficial degradation processes affecting the crystals of the mineral phases useful for provenance attribution (especially pyrite). To address this issue, an innovative workflow has been developed, centred on the application of X-ray micro-computed tomography (μ-CT) and micro-ablation treatments with a pulsed laser source prior to investigation with ion beam analysis (IBA). High-resolution μ-CT is employed to evaluate the alteration state of pyrite crystals within the entire volume of the lapis lazuli rock, and, if required, to identify the most suitable crystals on the surface for subsequent laser treatment. The micro-ablation procedure aims to create a small breach in the superficial altered layer (the irradiated areas are approximately 65 × 65 μm²), thereby exposing the preserved crystal beneath and allowing for the analysis of its trace element contents with IBA. The methodology of the workflow is presented, together with its first application to archaeological lapis lazuli material: three precious beads from the ancient Royal Cemetery of Ur (Mesopotamia, 3rd millennium BCE). The results are complemented by the application of a provenance protocol already validated that proved, for the first time using a micro-invasive analytical approach, a match between the Afghan quarry district and the raw material used to carve these beads.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-05988-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995359","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":"Erratum to: Isomer production studied with simultaneous decay curve analysis for alpha-particle induced reactions on natural platinum up to 29 MeV","authors":"Naohiko Otuka,&nbsp;Sándor Takács,&nbsp;Masayuki Aikawa,&nbsp;Shuichiro Ebata,&nbsp;Hiromitsu Haba","doi":"10.1140/epja/s10050-024-01482-5","DOIUrl":"10.1140/epja/s10050-024-01482-5","url":null,"abstract":"","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995668","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":"Editorial—Focus point on citizen science for physics: from education to crowdsourcing fundamental research","authors":"Despina Hatzifotiadou,&nbsp;Christian Caron","doi":"10.1140/epjp/s13360-024-05940-3","DOIUrl":"10.1140/epjp/s13360-024-05940-3","url":null,"abstract":"","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995289","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":"Improving smuon searches with neural networks","authors":"Alan S. Cornell,&nbsp;Benjamin Fuks,&nbsp;Mark D. Goodsell,&nbsp;Anele M. Ncube","doi":"10.1140/epjc/s10052-025-13748-3","DOIUrl":"10.1140/epjc/s10052-025-13748-3","url":null,"abstract":"<div><p>We demonstrate that neural networks can be used to improve search strategies, over existing strategies, in LHC searches for light electroweak-charged scalars that decay to a muon and a heavy invisible fermion. We propose a new search involving a neural network discriminator as a final cut and show that different signal regions can be defined using networks trained on different subsets of signal samples (distinguishing low-mass and high-mass regions). We also present a workflow using publicly-available analysis tools, that can lead, from background and signal simulation, to network training, through to finding projections for limits using an analysis and <span>ONNX</span> libraries to interface network and recasting tools. We provide an estimate of the sensitivity of our search from Run 2 LHC data, and projections for higher luminosities, showing a clear advantage over previous methods.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13748-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Massless limit and conformal soft limit for celestial massive amplitudes","authors":"Wei Fan","doi":"10.1140/epjc/s10052-025-13762-5","DOIUrl":"10.1140/epjc/s10052-025-13762-5","url":null,"abstract":"<div><p>In celestial holography, the massive and massless scalars in 4d space-time are represented by the Fourier transform of the bulk-to-boundary propagators and the Mellin transform of plane waves respectively. Recently, the 3pt celestial amplitude of one massive scalar and two massless scalars was discussed in arXiv:2312.08597. In this paper, we compute the 3pt celestial amplitude of two massive scalars and one massless scalar. Then we take the massless limit <span>(mrightarrow 0)</span> for one of the massive scalars, during which process the gamma function <span>(Gamma (1-Delta ))</span> appears. By requiring the resulting amplitude to be well-defined, that is it goes to the 3pt amplitude of arXiv:2312.08597, the scaling dimension of this massive scalar has to be conformally soft <span>(Delta rightarrow 1)</span>. The pole <span>(1/(1-Delta ))</span> coming from <span>(Gamma (1-Delta ))</span> is crucial for this massless limit. Without it the resulting amplitude would be zero. This can be compared with the conformal soft limit in celestial gluon amplitudes, where a singularity <span>(1/(Delta -1))</span> arises and the leading contribution comes from the soft energy <span>(omega rightarrow 0)</span>. The phase factors in the massless limit of massive conformal primary wave functions, discussed in arXiv:1705.01027, plays an import and consistent role in the celestial massive amplitudes. Furthermore, the subleading orders <span>(m^{2n})</span> can also contribute poles when the scaling dimension is analytically continued to <span>(Delta =1-n)</span> or <span>(Delta = 2)</span>, and we find that this consistent massless limit only exists for dimensions belonging to the generalized conformal primary operators <span>(Delta in 2-{mathbb {Z}}_{geqslant 0})</span> of massless bosons.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13762-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}