物理与天体物理最新文献

{"title":"Mamba time series forecasting with uncertainty quantification.","authors":"Pedro Pessoa, Paul Campitelli, Douglas P Shepherd, S Banu Ozkan, Steve Pressé","doi":"10.1088/2632-2153/adec3b","DOIUrl":"10.1088/2632-2153/adec3b","url":null,"abstract":"<p><p>State space models, such as Mamba, have recently garnered attention in time series forecasting (TSF) due to their ability to capture sequence patterns. However, in electricity consumption benchmarks, Mamba forecasts exhibit a mean error of approximately 8%. Similarly, in traffic occupancy benchmarks, the mean error reaches 18%. This discrepancy leaves us to wonder whether the prediction is simply inaccurate or falls within error given spread in historical data. To address this limitation, we propose a method to quantify the predictive uncertainty of Mamba forecasts. To achieve this, we propose a dual-network framework based on the Mamba architecture for probabilistic forecasting, where one network generates point forecasts while the other estimates predictive uncertainty by modeling variance. We abbreviate our tool, Mamba with probabilistic TSF, as Mamba-ProbTSF and the code for its implementation is available on GitHub https://github.com/PessoaP/Mamba-ProbTSF. Evaluating this approach on synthetic and real-world benchmark datasets, we find Kullback-Leibler divergence between the learned distributions and the data-which, in the limit of infinite data, should converge to zero if the model correctly captures the underlying probability distribution-reduced to the order of 10^-3 for synthetic data and 10^-1 for real-world benchmark. We find that in both the electricity consumption and traffic occupancy benchmark, the true trajectory stays within the predicted uncertainty interval at the two-sigma level about 95% of the time. We further compare Mamba-ProbTSF against leading probabilistic forecast methods, DeepAR and ARIMA, and show that our method consistently achieves lower forecast errors while offering more reliable uncertainty quantification. We end with a consideration of potential limitations, adjustments to improve performance, and considerations for applying this framework to processes for purely or largely stochastic dynamics where the stochastic changes accumulate as observed, for example, in pure Brownian motion or molecular dynamics trajectories.</p>","PeriodicalId":33757,"journal":{"name":"Machine Learning Science and Technology","volume":"6 3","pages":"035012"},"PeriodicalIF":6.3,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12281171/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144699735","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":"Beyond Euclid: an illustrated guide to modern machine learning with geometric, topological, and algebraic structures.","authors":"Mathilde Papillon, Sophia Sanborn, Johan Mathe, Louisa Cornelis, Abby Bertics, Domas Buracas, Hansen J Lillemark, Christian Shewmake, Fatih Dinc, Xavier Pennec, Nina Miolane","doi":"10.1088/2632-2153/adf375","DOIUrl":"10.1088/2632-2153/adf375","url":null,"abstract":"<p><p>The enduring legacy of Euclidean geometry underpins classical machine learning, which, for decades, has been primarily developed for data lying in Euclidean space. Yet, modern machine learning increasingly encounters richly structured data that is inherently non-Euclidean. This data can exhibit intricate geometric, topological and algebraic structure: from the geometry of the curvature of space-time, to topologically complex interactions between neurons in the brain, to the algebraic transformations describing symmetries of physical systems. Extracting knowledge from such non-Euclidean data necessitates a broader mathematical perspective. Echoing the 19th-century revolutions that gave rise to non-Euclidean geometry, an emerging line of research is redefining modern machine learning with non-Euclidean structures. Its goal: generalizing classical methods to unconventional data types with geometry, topology, and algebra. In this review, we provide an accessible gateway to this fast-growing field and propose a graphical taxonomy that integrates recent advances into an intuitive unified framework. We subsequently extract insights into current challenges and highlight exciting opportunities for future development in this field.</p>","PeriodicalId":33757,"journal":{"name":"Machine Learning Science and Technology","volume":"6 3","pages":"031002"},"PeriodicalIF":4.6,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315666/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144776367","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":"Metasurface‐Embedded Topological Photonic Crystal","authors":"Haoye Qin, Wenjing Lv, Jue Li, Zijin Yang, Zengping Su, Yuzhi Shi, Bo Li, Patrice Genevet, Qinghua Song","doi":"10.1002/lpor.202501032","DOIUrl":"https://doi.org/10.1002/lpor.202501032","url":null,"abstract":"Conventional topological photonic crystals (PhCs) often face limitations in tunability and functional diversity, while metasurfaces—though versatile—lack inherent topological protection. The concept of embedding metasurfaces into robust topological PhCs is presented for diverse wave and chirality manipulations without compromising their topological nature, contributing to a twofold topology‐functionality advantage in flat optics. By embedding tailored metasurfaces into topological PhC originating from the bound state in the continuum (BIC), chirality control, phase‐gradient wavefront engineering, and generation of exceptional points are achieved, while simultaneously preserving the momentum‐space topological singularity of BICs. This unified platform transcends the single‐functionality paradigm of topological photonics, enabling multifunctional light manipulation in compact, free‐space devices for applications in chiral sensing, vortex generation, and singular optics.","PeriodicalId":204,"journal":{"name":"Laser & Photonics Reviews","volume":"14 1","pages":""},"PeriodicalIF":11.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145002816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Wigner Path Integral Representation of the Density of States. Monte Carlo Simulation of Plasma Media.","authors":"Vladimir Filinov,&nbsp;Pavel Levashov,&nbsp;Alexander Larkin","doi":"10.1007/s10955-025-03508-8","DOIUrl":"10.1007/s10955-025-03508-8","url":null,"abstract":"<div><p>A new phase space path integral representation of quantum density of states (DOS) was derived for a strongly coupled plasma media representing hydrogen plasma and two-component Coulomb system with uniformly distributed in space uncorrelated positive charges (“protons”) simulating a neutralizing background (“OCP”). A path integral Monte Carlo approach was used for the calculation of DOS, energy and momentum distribution functions as well as spin–resolved radial distribution functions (RDFs). The RDFs for electrons with the same spin projection revealed exchange–correlation cavities. For a two-component hydrogen plasma (TCP) the Coulomb attraction results in the appearance of high peaks on the proton–electron RDFs at small interparticle distances, while for the “OCP” the analogous RDFs demonstrate an unexpected significant drop arising due to a three–particle effect caused by the electron repulsion preventing for any two electrons to be in the vicinity of any uncorrelated charge. At negative plasma energy the “OCP” DOS is a fast-decaying function, while in hydrogen plasma at a temperature of the order of 1 <span>(textrm{Ry} = 0.5text {Ha}approx 13.6)</span> eV the DOS shows a well-pronounced peak related to the bound states. Quantum effects make momentum distribution functions non-maxwellian with a power-law high-momentum asymptotics (“quantum tails”) even under the condition of thermodynamic equilibrium.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998547","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":"Ultra‐Wideband Transmissive Programmable Metasurface Enabled Near‐Field Holography and Far‐Field OAM Generation","authors":"Longpan Wang, Zhenyuan Li, Yuhua Chen, Xudong Bai, Zhenfei Li, Fuli Zhang, Xuetao Gan","doi":"10.1002/lpor.202501020","DOIUrl":"https://doi.org/10.1002/lpor.202501020","url":null,"abstract":"Transmissive programmable metasurface can offer notable benefits for the precise agile manipulation of electromagnetic (EM) waves, which is a promising candidate for radar detection, wireless communications, and spectral imaging. However, most previous studies typically face the challenge of narrow bandwidth and are constrained by relatively simple and single functionality. Here, an ultra‐wideband (UWB) transmissive programmable metasurface is proposed to conduct agile multifunctional EM modulation. The meta‐atom is designed with a butterfly‐shaped configuration and manipulated using two pin diodes, demonstrating high‐efficiency transmission with low insertion loss less than 1 dB and stable phase difference of 180° from 15.77 to 28.59 GHz, ranging from Ku to Ka‐band with a fractional bandwidth up to 57.7%. The transmissive programmable metasurface is further constructed, and its effectiveness for multifunctional EM modulation is verified both numerically and experimentally, which can conduct different functionalities, including near‐field holographic imaging at lower‐frequency Ku‐band and far‐field high‐purity orbital angular momentum (OAM) generation at higher‐frequency Ka‐band. The proposed strategy may enrich the functionalities of programmable metasurfaces, as well as open a new pathway toward UWB multifunctional applications.","PeriodicalId":204,"journal":{"name":"Laser & Photonics Reviews","volume":"18 1","pages":""},"PeriodicalIF":11.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145002817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Subcritical regimes in Poisson Boolean percolation on Ahlfors regular spaces","authors":"Yutaka Takeuchi","doi":"10.1007/s10955-025-03504-y","DOIUrl":"10.1007/s10955-025-03504-y","url":null,"abstract":"<div><p>We study the Poisson Boolean percolation model on Ahlfors regular metric measure spaces, extending fundamental results from the Euclidean spaces to more general geometric settings. Ahlfors regular space is a metric measure space that has a polynomial growth rate of metric balls. Our main result establishes that for s-Ahlfors regular spaces, the model exhibits a subcritical regime (no infinite clusters for small intensities) if and only if the radius distribution has a finite s-th moment, generalizing Gouéré’s result for the Euclidean spaces. We prove both directions: when an s-th moment is finite, we show that subcritical behavior exists using geometric properties of Ahlfors regular spaces, particularly the doubling property and the uniform perfectness. Conversely, when an s-th moment diverges, we demonstrate that infinite clusters occur almost surely for any positive intensity. The key technical innovation lies in handling the geometric challenges absent in Euclidean spaces, such as potentially empty annuli between concentric balls. We overcome this using uniform perfectness, which guarantees nonempty annuli under sufficient expansion, combined with doubling properties to control covering numbers. Our results apply broadly to Riemannian manifolds with nonnegative Ricci curvature, ultrametric spaces, unbounded Sierpinski gaskets, and snowflake constructions of Ahlfors regular spaces.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998549","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":"Revealing the Dynamics of Multiple Solitons and Soliton Pulsations in a Quartic‐Dispersion Fiber Laser","authors":"Zhenhong Wang, Yingjie Lin, Yufeng Song, Zhixiang Deng, Jun Liu, Chunxiang Zhang","doi":"10.1002/lpor.202501851","DOIUrl":"https://doi.org/10.1002/lpor.202501851","url":null,"abstract":"In the realm of ultrafast fiber lasers, emerging pure‐quartic solitons (PQSs) have attracted considerable attention owing to their unique energy‐width scaling advantage, fundamentally different from conventional second‐order dispersion solitons, and can offer unprecedented energy scaling‐up capabilities. In this paper, the complex PQS dynamics involving various soliton states, including multiple pure‐quartic solitons (MPQSs) and pulsating PQSs are observed and investigated in a passively mode‐locked fiber laser with net quartic dispersions. These underlying PQS dynamical phenomena are attributed to the interplay between the dominated fourth‐order dispersion and nonlinear effects. In the MPQS regime, several PQSs coexist in a single bunch, where the pulse separations between each other fall in the range of several hundreds of picoseconds. These PQS bunches can be termed as loosely‐bounded PQS solitons. In addition, the pulsating PQSs, manifesting periodic intensity oscillations accompanied with a variable pulse energy, are also observed. Their formation and evolution are susceptible to the pump power level, which is verified by the numerical simulations. These results can provide in‐depth insights into the intricate nonlinear dynamics of high‐order‐dispersion solitons within dissipative optical systems and the performance improvement of ultrafast fiber lasers in practical applications.","PeriodicalId":204,"journal":{"name":"Laser & Photonics Reviews","volume":"53 1","pages":""},"PeriodicalIF":11.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145002815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Long-Time Analysis of a Pair of On-lattice and Continuous Run-and-tumble Particles with Jamming Interactions","authors":"Arnaud Guillin,&nbsp;Leo Hahn,&nbsp;Manon Michel","doi":"10.1007/s10955-025-03485-y","DOIUrl":"10.1007/s10955-025-03485-y","url":null,"abstract":"<div><p>Run-and-Tumble Particles (RTPs) are a key model of active matter. They are characterized by alternating phases of linear travel and random direction reshuffling. By this dynamic behavior, they break time reversibility and energy conservation at the microscopic level. It leads to complex out-of-equilibrium phenomena such as collective motion, pattern formation, and motility-induced phase separation (MIPS). In this work, we study two fundamental dynamical models of a pair of RTPs with jamming interactions and provide a rigorous link between their discrete- and continuous-space descriptions. We demonstrate that as the lattice spacing vanishes, the discrete models converge to a continuous RTP model on the torus, described by a Piecewise Deterministic Markov Process (PDMP). This establishes that the invariant measures of the discrete models converge to that of the continuous model, which reveals finite mass at jamming configurations and exponential decay away from them. This indicates effective attraction, which is consistent with MIPS. Furthermore, we quantitatively explore the convergence towards the invariant measure. Such convergence study is critical for understanding and characterizing how MIPS emerges over time. Because RTP systems are non-reversible, usual methods may fail or are limited to qualitative results. Instead, we adopt a coupling approach to obtain more accurate, non-asymptotic bounds on mixing times. The findings thus provide deeper theoretical insights into the mixing times of these RTP systems, revealing the presence of both persistent and diffusive regimes.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998548","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":"RFI-HWT: Hybrid deep-learning algorithm for advanced RFI mitigation in radio astronomy","authors":"Zi-Yi You, Jian-Gang Luo, Yun-Rong Pan, Li Zhang, Lang Wang, Shuo Xiao, Ru-Shuang Zhao, Qi-Jun Zhi, Mao Yuan, Pei Wang, Zhi Ma, Jia-Tao Jiang, Xin Xu, Si-Yao Li","doi":"10.1051/0004-6361/202554423","DOIUrl":"https://doi.org/10.1051/0004-6361/202554423","url":null,"abstract":"<i>Context<i/>. High-sensitivity radio telescopes face increasing challenges of radio frequency interference (RFI) from various sources, including communication base stations, TV broadcasts, satellite signals, and so on. This RFI degrades the quality of observational data, posing a significant obstacle to the detection of pulsars and fast radio bursts (FRBs). Consequently, the development of effective RFI mitigation techniques is crucial.<i>Aims<i/>. To address this issue, this study aims to develop an advanced RFI mitigation algorithm, RFI-HWT, to overcome the limitations of existing machine-learning-based methods by integrating multi-scale and multidirectional signal decomposition with deep-learning-based denoising.<i>Methods<i/>. RFI-HWT integrates the multilevel two-dimensional wavelet transform (2D WT) with a deep-learning denoising model, namely DnCNN, to accurately identify and eliminate RFI via multi-scale and multidirectional signal decomposition. Furthermore, our model employs a self-training semi-supervised learning strategy, effectively utilizing both limited labeled and abundant unlabeled data during training to enhance its generalization and adaptability.<i>Results<i/>. Preliminary experiments on FAST and Parkes datasets demonstrate RFI-HWT’s superior performance: it achieves a 15% average signal-to-noise ratio (Avg.S/N) enhancement and 14% average structural similarity index measure (ASSIM) improvement over PRESTO’s “rfifind” method, outperforms the original 2D WT (11% Avg.S/N, 12% ASSIM gains), and surpasses the representative deep-learning methods RFI-Net (3.26% Avg.S/N, 4.46% ASSIM) and RFDL (2.12% Avg.S/N, 2.71% ASSIM). Furthermore, higher precision, recall, and F1-score values across both datasets confirm its strong generalization capability. CUDA parallelization ensures efficient processing while maintaining excellent performance.<i>Conclusions<i/>. These findings demonstrate that RFI-HWT is a feasible solution for mitigating multiple types of RFI sources and is capable of improving the data quality and efficiency of pulsar and FRB searches with high-sensitivity telescopes.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"104 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144995565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Extreme value distribution for gamma-ray-burst prompt data","authors":"S. Covino","doi":"10.1051/0004-6361/202555059","DOIUrl":"https://doi.org/10.1051/0004-6361/202555059","url":null,"abstract":"<i>Context<i/>. Gamma-ray bursts (GRBs) are known to be unpredictable in time and position. A few (observationally) exceptional events have been observed, such as GRB 221009A, which stands out for having a fluence and peak flux orders of magnitude higher than what has been measured so far.<i>Aims<i/>. Analysing the observed fluence, peak flux, or duration distributions typically requires one to assume some scenarios, and the consistency of the observed data with the predictions turns out to be an important model diagnostic. However, it is also of interest to model these distributions using general statistical properties that do not rely on specific model assumptions, allowing one to derive inferences only based on the consistency of the observed distributions with the hypothesis of one single population of events that generate them.<i>Methods<i/>. We obtained fluences, peak fluxes, and durations from the catalogues of GRBs observed by the CGRO-BATSE and Fermi-GBM instruments. We selected the extreme values in slots of equal duration and modelled their distributions using the generalised extreme value (GEV) formalism. The GEV distribution is a limit distribution naturally arising when the number of observations is large and is essentially independent of the phenomena producing the observed data.<i>Results<i/>. The distributions of extreme values for fluences, peak fluxes, and durations are consistent with being extracted from a single population of events, but the fluence and peak flux recorded for GRB 221009A constitute a striking exception. The probability of observing such an event, assuming it is a cosmological GRB, is low, with a median value of about one event per millennium for the fluence and about one event per century for the peak flux.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"15 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144995572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}