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Feynman's path integral approach is to sum over all possible spatio-temporal paths to reproduce the quantum wave function and the corresponding time evolution, which has enormous potential to reveal quantum processes in classical view. However, the complete characterization of quantum wave function with infinite paths is a formidable challenge, which greatly limits the application potential, especially in the strong-field physics and attosecond science. Instead of brute-force tracking every path one by one, here we propose deep-learning-performed strong-field Feynman's formulation with pre-classification scheme which can predict directly the final results only with data of initial conditions, so as to attack unsurmountable tasks by existing strong-field methods and explore new physics. Our results build up a bridge between deep learning and strong-field physics through the Feynman's path integral, which would boost applications of deep learning to study the ultrafast time-dependent dynamics in strong-field physics and attosecond science, and shed a new light on the quantum-classical correspondence.The wave function and the temporal evolution contain all information of quantum physics. However, they might be possibly the hardest to grasp in the classical world. Seventy years ago, Feynman proposed a path integral approach which has been viewed as the "sum over paths or histories" version of quantum mechanics, i.e. the wave function can be represented as a coherent superposition of contributions of all possible spatio-temporal paths [1,2]. Even though the Feynman's path integral (FPI) has been considered as the most fundamental way to interpret the quantum mechanics and answer what is the nature of measurements, the complete characterization of quantum wavepacket with all possible paths is formidable due to track ergodicity. Typically, only a very limited amount of paths could be accessed, and therefore only a reduced amount of information of quantum wavepacket could be obtained in different approximation methods so far.The development history of semiclassical methods based on FPI in strong-field physics, from the strong-field approximation (SFA) to the Coulomb corrected strongfield approximation (CCSFA) and quantum trajectory Monte Carlo methods, also proves that the more trajectories have been adopted, the more information could be extracted . As a result, despite of the notable success of these methods, there still exist a large number of unexplored regimes, including the open question about whether one could truly achieve the quantumclassical correspondence. Actually, with increasingly so-phisticated experiments, the limitation of existing semiclassical methods based on FPI for reproducing and explaining some quantum phenomena has been becoming increasingly evident due to the limited amount of paths, especially for the new attosecond measurements where a series of high-resolution photoelectron spectra with different pump-probe delays are needed to obtain attosecond time-resolved movies of electrons [25][26][27][...

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The monitoring data of the 13 stations in Xi’an city for the whole years of 2013 and 2014 was counted and analyzed. Obtaining the spatial and temporal distribution characteristics of PM2.5 was the goal. Cluster analysis and the wavelet transform were utilized to discuss the regional distribution characteristics of PM2.5 concentration (ρ(PM2.5)) and the main features of its yearly changes and sudden changes. Additionally, some relevant factors were taken into account to interpret the changes. The results show that ρ(PM2.5) in Xi’an during 2013 was generally higher than in 2014, it is high in winter and low in summer, and the high PM2.5 concentration centers are around the People’s Stadium and Caotan monitoring sites; For the regional PM2.5 distribution, the 13 sites can be divided into three categories, in which Textile city is Cluster 1, and High-tech Western is Cluster 2, and Cluster 3 includes the remaining 11 monitoring sites; the coefficient of goodness of the cluster analysis is 0.6761, which indicates that the result is acceptable. As for the yearly change, apart from June and July, the average ρ(PM2.5) concentration has been above the normal concentration criteria of Chinese National Standard (50 g/m3); cloudy weather and low winds are the major meteorological factors leading to the sudden changes of ρ(PM2.5).

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A new multichannel HCN interferometer has been developed on HL-2A tokamak, which is characterized by two techniques: (1) the wave-guide HCN laser with cavity length of 6 m to increase the optical resource power and (2) high response room temperature waveguide Schottky diode detectors to obtain good beat signal. The space resolution is 7 cm by the use of focusing metal mirrors mounted on the vacuum chamber and a compensated optical system. In the 2006 experiment campaign, this new interferometer has been applied for plasma density profile and density sawtooth measurement.

On 6 February 2023, two large earthquakes with magnitude 7.8 and 7.6 rocked south-central Türkiye and northwestern Syria. At the time of writing, the death toll exceeded 50,000 in Türkiye and 7200 in Syria. The epicenter of the first mainshock was located ∼15 km east of the east Anatolian fault (EAF), the second large earthquake (9 hr later) initiated ∼90 km to the north on the east–west-trending Sürgü fault. Aftershocks delineate fault lengths of ∼350 and ∼170 km, respectively. Using satellite and seismic data for first-order analyses of surface-fault offsets, space–time rupture evolution, and recorded ground motions, our study sheds light on the reasons for the extensive destruction. The first event ruptured the EAF bilaterally, lasted for ∼80 s, and created surface fault offsets of over 6 m. The second event also ruptured bilaterally with a duration of ∼35 s and more than 7 m surface offsets. Horizontal ground accelerations reached locally up to 2g in the first mainshock; severe and widespread shaking occurred in the Hatay-Antakia area with values near 0.5g. Both earthquakes are characterized by directivity effects and abrupt rupture cessation generating stopping phases that contributed to strong seismic radiation. Shaking was further aggravated locally by site-amplification effects.