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Author Correction: Enhanced energy coupling for indirect-drive fast-ignition fusion targets

Nature Physics 2020年第7期16卷 815-815页

作者： F. Zhang H. B. Cai W. M. Zhou Z. S. Dai L. Q. Shan H. Xu J. B. Chen F. J. Ge Q. Tang W. S. Zhang L. Wei D. X. Liu J. F. Gu H. B. Du B. Bi S. Z. Wu J. Li F. Lu H. Zhang B. Zhang M. Q. He M. H. Yu Z. H. Yang W. W. Wang H. S. Zhang B. Cui L. Yang J. F. Wu W. Qi L. H. Cao Z. Li H. J. Liu Y. M. Yang G. L. Ren C. Tian Z. Q. Yuan W. D. Zheng L. F. Cao C. T. Zhou S. Y. Zou Y. Q. Gu K. Du Y. K. Ding B. H. Zhang S. P. Zhu W. Y. Zhang X. T. He Science and Technology on Plasma Physics Laboratory Laser Fusion Research Center CAEP Mianyang China Institute of Applied Physics and Computational Mathematics Beijing China HEDPS Center for Applied Physics and Technology Peking University Beijing China College of Computing Science National University of Defense Technology Changsha China Center for Advanced Material Diagnostic Technology Shenzhen Technology University Shenzhen China Graduate School China Academy of Engineering Physics Beijing China

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Accelerating large partial EVD/SVD calculations by filtered block Davidson methods

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Science China mathematics 2016年第8期59卷 1635-1662页

作者： ZHOU Yunkai WANG Zheng ZHOU Aihui Department of Mathematics Southern Methodist University LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems Science Chinese Academy of Sciences

Partial eigenvalue decomposition(PEVD) and partial singular value decomposition(PSVD) of large sparse matrices are of fundamental importance in a wide range of applications, including latent semantic indexing, spectral clustering, and kernel methods for machine learning. The more challenging problems are when a large number of eigenpairs or singular triplets need to be computed. We develop practical and efficient algorithms for these challenging problems. Our algorithms are based on a filter-accelerated block Davidson *** types of filters are utilized, one is Chebyshev polynomial filtering, the other is rational-function filtering by solving linear equations. The former utilizes the fastest growth of the Chebyshev polynomial among same degree polynomials; the latter employs the traditional idea of shift-invert, for which we address the important issue of automatic choice of shifts and propose a practical method for solving the shifted linear equations inside the block Davidson method. Our two filters can efficiently generate high-quality basis vectors to augment the projection subspace at each Davidson iteration step, which allows a restart scheme using an active projection subspace of small dimension. This makes our algorithms memory-economical, thus practical for large PEVD/PSVD calculations. We compare our algorithms with representative methods, including ARPACK, PROPACK, the randomized SVD method, and the limited memory SVD method. Extensive numerical tests on representative datasets demonstrate that, in general, our methods have similar or faster convergence speed in terms of CPU time, while requiring much lower memory comparing with other methods. The much lower memory requirement makes our methods more practical for large-scale PEVD/PSVD computations.

关键词： partial EVD/SVD polynomial filter rational filter kernel graph

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A Crank-Nicolson finite element method and the optimal error estimates for the modified time-dependent Maxwell-Schrödinger equations

arXiv

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arXiv 2017年

作者： Ma, Chupeng Cao, Liqun Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China LSEC NCMIS Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China

In this paper we consider the initial-boundary value problem for the time-dependent Maxwell-Schrödinger equations, which arises in the interaction between the matter and the electromagnetic field for the semiconductor quantum devices. A Crank-Nicolson finite element method for solving the problem is presented. The optimal energy-norm error estimates for the numerical algorithm without any time-step restrictions are derived. Numerical tests are then carried out to confirm the theoretical results. Copyright © 2017, The Authors. All rights reserved.

关键词： Finite element method

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Snowmass2021 Cosmic Frontier CF6 White Paper: Multi-Experiment Probes for Dark Energy - Transients

arXiv

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arXiv 2022年

作者： Kim, Alex G. Palmese, Antonella Pereira, Maria E.S. Aldering, Greg Andrade-Oliveira, Felipe Annis, James Bailey, Stephen BenZvi, Segev Braga-Neto, Ulysses Courbin, Frédéric Garcia, Alyssa Jeffery, David Narayan, Gautham Perlmutter, Saul Soares-Santos, Marcelle Treu, Tommaso Wang, Lifan Aguiar, Odylio D. Akrami, Yashar Birrer, Simon Bom, Clécio R. Buckley-Geer, Elizabeth Cabuk, Nazim Cabuk, Senem Cadonati, Laura Caliskan, Mesut Chen, Thomas Y. Davis, Tamara M. Eskilt, Johannes R. Esteves, Johnny Ferraro, Simone Fisher, Robert Gamezo, Vadim N. García-Bellido, Juan Gill, Mandeep S.S. Herner, Kenneth Huterer, Dragan Ishak, Mustapha Iyer, Bala Jin, Shang-Jie Kilpatrick, Charles D. Koopmans, Léon V.E. Lagos, Macarena Lahav, Ofer Makler, Martín Nugent, Peter Nunes, Rafael C. Poludnenko, Alexei Y. Radice, David Rao, Suvrat Santana-Silva, Luidhy Sasaki, Misao Sathyaprakash, Bangalore Shafieloo, Arman Shao, Lijing Sherman, Nora Singh, Rajeev Smith, Joshua Tohuvavohu, Aaron Physics Division Lawrence Berkeley National Laboratory Berkeley94720 CA United States Department of Physics University of California Berkeley 366 LeConte Hall MC 7300 BerkeleyCA94720 United States NASA Einstein Germany Hamburger Sternwarte Universität Hamburg Gojenbergsweg 112 Hamburg21029 Germany Department of Physics University of Michigan Ann ArborMI48109 United States Fermi National Accelerator Laboratory P. O. Box 500 BataviaIL60510 United States Department of Physics and Astronomy University of Rochester RochesterNY14627 United States Department of Physics and Astronomy Texas A&M University College StationTX77845 United States Observatoire de Sauverny Versoix1290 Switzerland Department of Physics and Astronomy University of Nevada United States University of Illinois at Urbana-Champaign UrbanaIL61801 United States Department of Physics and Astronomy University of California Los AngelesCA90095-1547 United States Instituto Nacional de Pesquisas Espaciais São José dos Campos São Paulo12227-010 Brazil CERCA ISO Department of Physics Case Western Reserve University 10900 Euclid Avenue ClevelandOH44106 United States Department of Physics Imperial College London Blackett Laboratory Prince Consort Road LondonSW7 2AZ United Kingdom Laboratoire de Physique de l'École Normale Supérieure ENS Université PSL CNRS Sorbonne Université Université de Paris ParisF-75005 France Kavli Institute for Particle Astrophysics and Cosmology Department of Physics Stanford University StanfordCA94305 United States Centro Brasileiro de Pesquisas Físicas Rua Dr. Xavier Sigaud 150 RJ Rio de JaneiroCEP 22290-180 Brazil Department of Astronomy and Astrophysics University of Chicago ChicagoIL60637 United States Faculty of Engineering Department of Physics Engineering Ankara University Turkey Faculty of Science Department of Astronomy and Space Sciences Ankara University Turkey Center for Relativistic Astrophysics School of Physics Georgia Inst

This invited Snowmass 2021 White Paper highlights the power of joint-analysis of astronomical transients in advancing HEP Science and presents research activities that can realize the opportunities that come with current and upcoming projects. Transients of interest include gravitational wave events, neutrino events, strongly-lensed quasars and supernovae, and Type Ia supernovae specifically. These transients can serve as probes of cosmological distances in the Universe and as cosmic laboratories of extreme strong-gravity, high-energy physics. Joint analysis refers to work that requires significant coordination from multiple experiments or facilities so encompasses Multi-Messenger Astronomy and optical transient discovery and distributed follow-up programs. Copyright © 2022, The Authors. All rights reserved.

关键词： Probes

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A singularity-based eigenfunction decomposition for Kohn-Sham equations

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Science China mathematics 2016年第8期59卷 1623-1634页

作者： ZHANG Xin ZHOU Aihui SWIEE Southwest China Research Institute of Electronic Equipment LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems Science Chinese Academy of Sciences

We show that the eigenfunctions of Kohn-Sham equations can be decomposed as ■ = F ψ, where F depends on the Coulomb potential only and is locally Lipschitz, while ψ has better regularity than ■.

关键词： decomposition eigenfunction Kohn-Sham equation full-potential regularity singularity

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A New Fully Polynomial Time Approximation Scheme for the Interval Subset Sum Problem

arXiv

引用

arXiv 2017年

作者： Diao, Rui Liu, Ya-Feng Dai, Yu-Hong State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China

The interval subset sum problem (ISSP) is a generalization of the well-known subset sum problem. Given a set of intervals {[ai,1, ai,2]}ni=1 and a target integer T, the ISSP is to find a set of integers, at most one from each interval, such that their sum best approximates the target T but cannot exceed it. In this paper, we first study the computational complexity of the ISSP. We show that the ISSP is relatively easy to solve compared to the 0-1 Knapsack problem (KP). We also identify several subclasses of the ISSP which are polynomial time solvable (with high probability), albeit the problem is generally NP-hard. Then, we propose a new fully polynomial time approximation scheme (FPTAS) for solving the general ISSP problem. The time and space complexities of the proposed scheme are O (n max {1/ǫ, log n}) and O (n + 1/ǫ), respectively, where ǫ is the relative approximation error. To the best of our knowledge, the proposed scheme has almost the same time complexity but a significantly lower space complexity compared to the best known scheme. Both the correctness and efficiency of the proposed scheme are validated by numerical simulations. In particular, the proposed scheme successfully solves ISSP instances with n = 100, 000 and ǫ = 0.1% within one second. Copyright © 2017, The Authors. All rights reserved.

关键词： computational complexity

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High order conformal symplectic and ergodic schemes for stochastic Langevin equation via generating functions

arXiv

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arXiv 2017年

作者： Hong, Jialin Sun, Liying Wang, Xu Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China

In this paper, we consider the stochastic Langevin equation with additive noises, which possesses both conformal symplectic geometric structure and ergodicity. We propose a methodology of constructing high weak order conformal symplectic schemes by converting the equation into an equivalent autonomous stochastic Hamiltonian system and modifying the associated generating function. To illustrate this approach, we construct a specific second order numerical scheme, and prove that its symplectic form dissipates exponentially. Moreover, for the linear case, the proposed scheme is also shown to inherit the ergodicity of the original system, and the temporal average of the numerical solution is a proper approximation of the ergodic limit over long time. Numerical experiments are given to verify these theoretical *** subject classification: 60H08, 60H35, 65C30. Copyright © 2017, The Authors. All rights reserved.

关键词： Differential equations

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The Cauchy two-matrix model, C-Toda lattice and CKP hierarchy

arXiv

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arXiv 2018年

作者： Li, Chunxia Li, Shi-Hao School of Mathematical Sciences Capital Normal University Beijing100048 China Lsec Institute of Computational Mathematics and Scientific Engineering Computing Amss Chinese Academy of Sciences P.O.Box 2719 Beijing100190 China Department of Mathematical Sciences University of the Chinese Academy of Sciences Beijing China

This paper mainly talks about the Cauchy two-matrix model and its corresponding integrable hierarchy with the help of orthogonal polynomials theory and Toda-type equations. Starting from the symmetric reduction of Cauchy biorthogonal polynomials, we derive the Toda equation of CKP type (or the C-Toda lattice) as well as its Lax pair by introducing time flows. Then, matrix integral solutions to the C-Toda lattice are extended to give solutions to the CKP hierarchy which reveals the time-dependent partition function of the Cauchy two-matrix model is nothing but the τ -function of the CKP hiearchy. At last, the connection between the Cauchy two-matrix model and Bures ensemble is established from the point of view of integrable *** Codes 37K10, 33C47, 15A15, 41A21 Copyright © 2018, The Authors. All rights reserved.

关键词： Polynomials

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Positivity preserving DG schemes for a Boltzmann - Poisson model of electrons in semiconductors in curvilinear momentum coordinates

arXiv

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arXiv 2017年

作者： Morales, José A. E. Gamba, Irene M. Endeve, Eirik Hauck, Cory TU Wien Institute for Analysis and Scientific Computing University of Texas at Austin Institute for Computational Engineering and Sciences Department of Mathematics Oak Ridge National Lab Computational and Applied Mathematics Group

The work presented in this paper is related to the development of positivity preserving Discontinuous Galerkin (DG) methods for Boltzmann - Poisson (BP) computational models of electronic transport in semiconductors. We pose the Boltzmann Equation for electron transport in curvilinear coordinates for the momentum. We consider the 1D diode problem with azimuthal symmetry, which is a 3D plus time problem. We choose for this problem the spherical coordinate system p→(|p→|, μ = cosθ, φ), slightly different to the choice in previous DG solvers for BP, because its DG formulation gives simpler integrals involving just piecewise polynomial functions for both transport and collision terms. Applying the strategy of Zhang & Shu, [1], [2], Cheng, Gamba, Proft, [3], and Endeve et al. [4], we treat the collision operator as a source term, and find convex combinations of the transport and collision terms which guarantee the positivity of the cell average of our numerical probability density function at the next time step. The positivity of the numerical solution to the pdf in the whole domain is guaranteed by applying the limiters in [1], [2] that preserve the cell average but modify the slope of the piecewise linear solutions in order to make the function non - negative. In addition of the proofs of positivity preservation in the DG scheme, we prove the stability of the semi-discrete DG scheme under an entropy norm, using the dissipative properties of our collisional operator given by its entropy inequalities. The entropy inequality we use depends on an exponential of the Hamiltonian rather than the Maxwellian associated just to the kinetic energy. Copyright © 2017, The Authors. All rights reserved.

关键词： Galerkin methods

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Population of Merging Compact Binaries Inferred Using Gravitational Waves through GWTC-3

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Physical Review X 2023年第1期13卷 011048-011048页

作者： R. Abbott T. D. Abbott F. Acernese K. Ackley C. Adams N. Adhikari R. X. Adhikari V. B. Adya C. Affeldt D. Agarwal M. Agathos K. Agatsuma N. Aggarwal O. D. Aguiar L. Aiello A. Ain P. Ajith T. Akutsu P. F. de Alarcón S. Akcay S. Albanesi A. Allocca P. A. Altin A. Amato C. Anand S. Anand A. Ananyeva S. B. Anderson W. G. Anderson M. Ando T. Andrade N. Andres T. Andrić S. V. Angelova S. Ansoldi J. M. Antelis S. Antier F. Antonini S. Appert Koji Arai Koya Arai Y. Arai S. Araki A. Araya M. C. Araya J. S. Areeda M. Arène N. Aritomi N. Arnaud M. Arogeti S. M. Aronson K. G. Arun H. Asada Y. Asali G. Ashton Y. Aso M. Assiduo S. M. Aston P. Astone F. Aubin C. Austin S. Babak F. Badaracco M. K. M. Bader C. Badger S. Bae Y. Bae A. M. Baer S. Bagnasco Y. Bai L. Baiotti J. Baird R. Bajpai M. Ball G. Ballardin S. W. Ballmer A. Balsamo G. Baltus S. Banagiri D. Bankar J. C. Barayoga C. Barbieri B. C. Barish D. Barker P. Barneo F. Barone B. Barr L. Barsotti M. Barsuglia D. Barta J. Bartlett M. A. Barton I. Bartos R. Bassiri A. Basti M. Bawaj J. C. Bayley A. C. Baylor M. Bazzan B. Bécsy V. M. Bedakihale M. Bejger I. Belahcene V. Benedetto D. Beniwal T. F. Bennett J. D. Bentley M. BenYaala F. Bergamin B. K. Berger S. Bernuzzi C. P. L. Berry D. Bersanetti A. Bertolini J. Betzwieser D. Beveridge R. Bhandare U. Bhardwaj D. Bhattacharjee S. Bhaumik I. A. Bilenko G. Billingsley S. Bini R. Birney O. Birnholtz S. Biscans M. Bischi S. Biscoveanu A. Bisht B. Biswas M. Bitossi M.-A. Bizouard J. K. Blackburn C. D. Blair D. G. Blair R. M. Blair F. Bobba N. Bode M. Boer G. Bogaert M. Boldrini L. D. Bonavena F. Bondu E. Bonilla R. Bonnand P. Booker B. A. Boom R. Bork V. Boschi N. Bose S. Bose V. Bossilkov V. Boudart Y. Bouffanais A. Bozzi C. Bradaschia P. R. Brady A. Bramley A. Branch M. Branchesi J. Brandt J. E. Brau M. Breschi T. Briant J. H. Briggs A. Brillet M. Brinkmann P. Brockill A. F. Brooks J. Brooks D. D. Brown S. Brunett G. Bruno R. Bruntz J. Bryant T. Bulik H. J. Bulten A. Buonanno R. Buscicchio D. Buskulic C. Buy R. L. Byer L. Cadonati LIGO Laboratory California Institute of Technology Pasadena California 91125 USA Louisiana State University Baton Rouge Louisiana 70803 USA Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy OzGrav School of Physics & Astronomy Monash University Clayton 3800 Victoria Australia LIGO Livingston Observatory Livingston Louisiana 70754 USA University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201 USA OzGrav Australian National University Canberra Australian Capital Territory 0200 Australia Max Planck Institute for Gravitational Physics (Albert Einstein Institute) D-30167 Hannover Germany Leibniz Universität Hannover D-30167 Hannover Germany Inter-University Centre for Astronomy and Astrophysics Pune 411007 India University of Cambridge Cambridge CB2 1TN United Kingdom Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany University of Birmingham Birmingham B15 2TT United Kingdom Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA) Northwestern University Evanston Illinois 60208 USA Instituto Nacional de Pesquisas Espaciais 12227-010 São José dos Campos São Paulo Brazil Gravity Exploration Institute Cardiff University Cardiff CF24 3AA United Kingdom INFN Sezione di Pisa I-56127 Pisa Italy International Centre for Theoretical Sciences Tata Institute of Fundamental Research Bengaluru 560089 India Gravitational Wave Science Project National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Advanced Technology Center National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Universitat de les Illes Balears IAC3–IEEC E-07122 Palma de Mallorca Spain University College Dublin Dublin 4 Ireland INFN Sezione di Torino I-10125 Torino Italy Università di Napoli “Federico II” Complesso Universitario di Monte S. Angelo I-80126 Napoli

We report on the population properties of compact binary mergers inferred from gravitational-wave observations of these systems during the first three LIGO-Virgo observing runs. The Gravitational-Wave Transient Catalog 3 (GWTC-3) contains signals consistent with three classes of binary mergers: binary black hole, binary neutron star, and neutron star–black hole mergers. We infer the binary neutron star merger rate to be between 10 and 1700 Gpc−3 yr−1 and the neutron star–black hole merger rate to be between 7.8 and 140 Gpc−3 yr−1, assuming a constant rate density in the comoving frame and taking the union of 90% credible intervals for methods used in this work. We infer the binary black hole merger rate, allowing for evolution with redshift, to be between 17.9 and 44 Gpc−3 yr−1 at a fiducial redshift (z=0.2). The rate of binary black hole mergers is observed to increase with redshift at a rate proportional to (1+z)κ with κ=2.9−1.8+1.7 for z≲1. Using both binary neutron star and neutron star–black hole binaries, we obtain a broad, relatively flat neutron star mass distribution extending from 1.2−0.2+0.1 to 2.0−0.3+0.3M⊙. We confidently determine that the merger rate as a function of mass sharply declines after the expected maximum neutron star mass, but cannot yet confirm or rule out the existence of a lower mass gap between neutron stars and black holes. We also find the binary black hole mass distribution has localized over- and underdensities relative to a power-law distribution, with peaks emerging at chirp masses of 8.3−0.5+0.3 and 27.9−1.8+1.9M⊙. While we continue to find that the mass distribution of a binary’s more massive component strongly decreases as a function of primary mass, we observe no evidence of a strongly suppressed merger rate above approximately 60M⊙, which would indicate the presence of a upper mass gap. Observed black hole spins are small, with half of spin magnitudes below χi≈0.25. While the majority of spins are preferentially aligned wi

关键词： Gravitational wave sources Gravitational waves Gravitational wave detection

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