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Inflation Scheme Derived from Universal Wave Function Interpretation of String Theory

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Journal of Physical Science and Application 2017年第4期7卷 33-37页

作者： Dr. Zhi Gang Sha Rulin Xiu Institute of Soul Healing and Enlightenment 30 Wertheim Court Unit 27D Richmond Hill Ontario L4B 1B9 Canada Hawaii theoretical physics Research {2. 16-266 E. Kipimana St Keaau HI 96749 USA

Inflation is the most commonly accepted theory in cosmology to explain why the universe appears flat, homogeneous, and isotropic, as well as the origin of the large-scale structure of the cosmos and why no magnetic monopoles have been detected. However, so far, the origin of the inflation epoch and what is the hypothetical field, the inflation, giving rise to inflation, remains unknown. String theory is one of the promising candidates for the grand unification theory. Grand unification theory is to use one mathematic formula to describe everything. In this work, we study the inflation scheme in a new development in string theory, UWFIST （universal wave function interpretation of string theory）. We show that from UWFIST we can derive from the fundamental theory that the long-range vibration is the possible candidate of inflation. We estimate the vacuum energy created by the long-range vibration and show that it can indeed drive the inflation.

关键词： Inflation string theory universal wave function interpretation of string theory grand unification theory.

Restoration of the focal parameters for an extreme-power laser pulse with ponderomotively scattered proton spectra by using a neural network algorithm

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Matter and Radiation at Extremes 2023年第1期8卷 28-42页

作者： N.D.Bukharskii O.E.Vais Ph.A.Korneev V.Yu.Bychenkov National Research nuclear University MEPhI MoscowRussian Federation P.N.Lebedev Physical Institute MoscowRussian Federation center for Fundamental and Applied Research Dukhov Research Institute of Automatics(VNIIA)MoscowRussian Federation

A neural network-based approach is proposed both for reconstructing the focal spot intensity profile and for estimating the peak intensity of a high-power tightly focused laser pulse using the angular energy distributions of protons accelerated by the pulse from rarefied *** these purposes,we use a convolutional neural network *** and testing datasets are calculated using the test particle method,with the laser description in the form of Stratton-Chu integrals,which model laser pulses focused by an off-axis parabolic mirror down to the diffraction *** demonstrate the power and robustness of this method,we discuss the reconstruction of axially symmetric intensity profiles for laser pulses with intensities and focal diameters in the ranges of 10^(2.)-10^(2.) W cm^(−2. and ~(1-4)λ,*** approach has prospects for implementation at higher intensities and with asymmetric laser beams,and it can provide a valuable diagnostic method for emerging extremely intense laser facilities.

关键词： network pulse power

Realistic flat-band model based on degenerate p-orbitals in two-dimensional ionic materials

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Science Bulletin 2021年第8期66卷 765-770,M0003页

作者： Jiang Zeng Ming Lu Haiwen Liu Hua Jiang X.C.Xie International center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Beijing Academy of Quantum Information Sciences Beijing 100871China center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Science and Technology Soochow UniversitySuzhou 215006China Beijing Academy of Quantum Information Sciences Beijing 100193China CAS center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100871China

Though several theoretical models have been proposed to design electronic flat-bands, the definite experimental realization in two-dimensional atomic crystal is still lacking. Here we propose a novel and realistic flat-band model based on threefold degenerate p-orbitals in two-dimensional ionic materials. Our theoretical analysis and first-principles calculations show that the proposed flat-band can be realized in 1 T layered materials of alkali-metal chalogenides and metal-carbon group compounds. Some of the former are theoretically predicted to be stable as layered materials(e.g., K2.S), and some of the latter have been experimentally fabricated in previous works(e.g., Gd2.CCl2.. More interestingly, the flat-band is partially filled in the heterostructure of a K2.S monolayer and graphene layers. The spin polarized nearly flatband can be realized in the ferromagnetic state of a Gd2.CCl2.monolayer, which has been fabricated in experiments. Our theoretical model together with the material predictions provide a realistic platform for the study of flat-bands and related exotic quantum phases.

关键词： Flat-band Degenerate orbitals Material realization 1T structure Partially filled

Binding kinetics for drug-receptor interactions

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Binding kinetics for drug-receptor interactions

Machine learning for deep elastic strain engineering of semiconductor electronic band structure and effective mass

中国化学会第2.届学术年会

作者： Fang Bai Yechun Xu Jing Chen Qiufeng Liu Junfeng Gu Xicheng Wang Jianpeng Ma José Nelson Onuchic Honglin Li Hualiang Jiang Department of Engineering Mechanics State Key Laboratory of Structural Analysis for Industrial Equipment Faculty of Chemical Environmental and Biological Science and Technology Dalian University of Technology Drug Discovery and Design center State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences center for theoretical Biological {2. Rice University

Drug‐target residence time（t=1/koff,koff is the dissociation rate constant）has become an important index in discovering better‐or best‐in‐class ***,little effort has been dedicated to develop computational methods that can accurately predict this kinetic parameter or related parameters,koff and activation free energy of dissociation（）.Recently,energy landscape theory that has been developed to understand protein folding and function is extended to develop a generally applicable computational framework that is able to construct a complete ligand‐target binding free energy landscape（BFEL）.This enables both the binding affinity and the binding kinetics to be accurately *** applied this method to simulate the binding events of the anti‐Alzheimer’s disease drugs（‐）‐Huperzine A（HupA）and E2.2. to the target acetylcholinesterase（AChE）.The computational results are in excellent agreement with our concurrent experimental *** the predicted values of binding free energy and activation free energies of association and dissociation only deviate from the experimental data by less than 2.kcal/*** method also provides atomic resolution information for the ligand binding pathways,which may be useful in designing more potent AChE *** expect this methodology to be widely applicable to drug discovery and development.

关键词：

来源： cnki会议评论

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npj Computational Materials 2021年第1期7卷 694-703页

作者： Evgenii Tsymbalov Zhe Shi Ming Dao Subra Suresh Ju Li Alexander Shapeev Skolkovo Institute of Science and Technology MoscowRussia Department of Materials Science and Engineering and Department of nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Nanyang Technological University SingaporeRepublic of Singapore

The controlled introduction of elastic strains is an appealing strategy for modulating the physical properties of semiconductor *** the recent discovery of large elastic deformation in nanoscale specimens as diverse as silicon and diamond,employing this strategy to improve device performance necessitates first-principles computations of the fundamental electronic band structure and target figures-of-merit,through the design of an optimal straining *** simulations,however,call for approaches that combine deep learning algorithms and physics of deformation with band structure calculations to custom-design electronic and optical *** by this challenge,we present here details of a machine learning framework involving convolutional neural networks to represent the topology and curvature of band structures in *** calculations enable us to identify ways in which the physical properties can be altered through“deep”elastic strain engineering up to a large fraction of the ideal *** capable of active learning and informed by the underlying physics were presented here for predicting the bandgap and the band *** training a surrogate model with ab initio computational data,our method can identify the most efficient strain energy pathway to realize physical property *** power of this method is further demonstrated with results from the prediction of strain states that influence the effective electron *** illustrate the applications of the method with specific results for diamonds,although the general deep learning technique presented here is potentially useful for optimizing the physical properties of a wide variety of semiconductor materials。

关键词： strain deformation electronic

Isovector Dipole Giant Resonances:a Relativistic Vlasov Equation Approach

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Chinese physics Letters 1995年第3期12卷 144-147页

作者： ZHOU Baosen CAI Yanhuang ZHU Zhiyuan Institute of nuclear Research Academia SinicaShanghai 201800 China center of Advanced Science and Technology(World Laboratory) P.O.Box 8730Beijing 100080

In the framework of relativistic quantum hadron dynamical theory,under semiclassical approximation and taking the vacuum fluctuation into account,a relativistic Vlasov equation(RVE)has been *** RVE and considering other relativistic effects,we have studied the isovector dipole giant resonances built on ground state in spherical *** main results shown that the resonance energies for each multipole are larger than those obtained from the non-relativistic classical Vlasov *** by means of choosing a reasonable symmetry potential as 100MeV,the relativistic results can fit the experimental results very well.

关键词： relativistic symmetry dipole

Chemically induced large-gap quantum anomalous Hall insulator states in Ⅲ-Bi honeycombs

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npj Computational Materials 2017年第1期3卷 130-136页

作者： Christian P.Crisostomo Zhi-Quan Huang Chia-Hsiu Hsu Feng-Chuan Chuang Hsin Lin Arun Bansil Department of physics National Sun Yat-Sen UniversityKaohsiung 804Taiwan Multidisciplinary and Data Science Research center National Sun Yat-Sen UniversityKaohsiung 804Taiwan Centre for Advanced 2. Materials and Graphene Research Centre National University of SingaporeSingapore 117546Singapore Department of physics National University of SingaporeSingapore 117542Singapore Department of physics Northeastern UniversityBostonMA 02115USA

The search for novel materials with new functionalities and applications potential is continuing to *** anomalous Hall(QAH)effect was recently realized in magnetic topological insulators(TIs)but only at extremely low ***,based on our first-principles electronic structure calculations,we predict that chemically functionalized Ⅲ-Bi honeycombs can support large-gap QAH insulating ***,we show that functionalized AlBi and TlBi films harbor QAH insulator *** and InBi are identified as semimetals with non-zero Chern ***,TlBi exhibits a robust QAH phase with a band gap as large as 466 meV in a buckled honeycomb structure functionalized on one ***,the electronic spectrum of a functionalized TlBi nanoribbon with zigzag edge is shown to possess only one chiral edge band crossing the Fermi level within the band *** results suggest that Ⅲ-Bi honeycombs would provide a new platform for developing potential spintronics applications based on the QAH effect.

关键词： effect insulator quantum

One-dimensional PT-symmetric acoustic heterostructure

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Chinese physics B 2022年第12期31卷 289-294页

作者： Hai-Xiao Zhang Wei Xiong Ying Cheng Xiao-Jun Liu Department of physics MOE Key Laboratory of Modern AcousticsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China School of Electrical and Information Engineering Changzhou Institute of TechnologyChangzhou 213032China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

The explorations of parity-time(PT)-symmetric acoustics have resided at the frontier in physics,and the pre-existing accessing of exceptional points typically depends on Fabry-Perot resonances of the coupling interlayer sandwiched between balanced gain and loss ***,the concise PT-symmetric acoustic heterostructure,eliminating extra interactions caused by the interlayer,has not been researched in *** we derive the generalized unitary relation for one-dimensional(1D)PT-symmetric heterostructure of arbitrary complexity,and demonstrate four disparate patterns of anisotropic transmission resonances(ATRs)accompanied by corresponding spontaneous phase *** a special case of ATR,the occasional bidirectional transmission resonance reconsolidates the ATR frequencies that split when waves incident from opposite directions,whose spatial profiles distinguish from a unitary *** derived theoretical relation can serve as a predominant signature for the presence of PT symmetry and PT-symmetry-breaking transition,which may provide substantial support for the development of prototype devices with asymmetric acoustic responses.

关键词： acoustic PT-symmetric heterostructure anisotropic transmission resonance occasional bidirectional transmission resonance

Measurement of the(n,2.)reaction cross-sections of iodine and cesium induced by D-T neutrons with covariance analysis

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中国物理C:英文版 2023年第9期47卷 86-94页

作者：兰长林牛玉鑫魏玉婷陆芳潇杨宪林续瑞瑞张玥葛裕杰王家豪姜功 School of nuclear Science and Technology Lanzhou UniversityLanzhou 730000China China National nuclear Corporation Beijing 100045China Key Laboratory of nuclear Data China Institute of Atomic EnergyBeijing 102413China

The cross-sections of the 12.I(n,2.)12.I and 133Cs(n,2.)132.s reactions at neutron energies of 13.83±0.05,14.33±0.10,and 14.79±0.10 MeV were measured relative to the 93Nb(n,2.)92.Nb reaction using the activation technique in combination with off-lineγ-ray spectrometry.A neutron beam was generated from the T(d,n)4He reaction using the K-400 neutron generator at the China Academy of Engineering *** the correlations between different attributes,detailed uncertainty propagation was performed using covariance analysis,and the cross-sections were reported with their uncertainties and correlation *** uncertainty of the measurement cross-sections ranged from 4.84 to 5.90%,which is lower than previous experimental ***,the theoretical excitation functions of the 12.I(n,2.)12.I and 133Cs(n,2.)132.s reactions were calculated using the TALYS-1.95 and EMPIRE-3.2.3 ***,the experimentally determined cross-sections were analyzed by comparing them with literature data available in the EXFOR database and evaluated nuclear data in the ENDF/B-VIII.0,JEFF-3.3,JENDL-5,BROND-3.1,CENDL-3.2.and TENDL-2.2. *** with the values previously reported in the 13.8-14.8 MeV energy region,the precision of the results obtained in this study was greatly *** current experimental results with thorough uncertainties and covariance information are critical for verifying the reliability of the theoretical model and improving the quality of the nuclear database.

关键词： 12.I(n,2.)12.I 133Cs(n,2.)132.s cross-section neutron activation covariance analysis excitation function