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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan Xie Yuchen Wang Haiping Huang PMI lab School of Physics Sun Yat-sen University Guangdong Provincial Key laboratory of Magnetoelectric physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural networks trained by backpropagation can be easily fooled by adversarial examples. To design a semantically meaningful representation learning, we discard backpropagation, and instead, propose a local contrastive learning, where the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,while those of different labels repel(akin to fermion). This layer-wise learning is local in nature, being biologically plausible.A statistical mechanics analysis shows that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIST benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural networks

Three-dimensional Bose Einstein condensate vortex solitons under optical lattice and harmonic confinements

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Chinese physics B 2013年第3期22卷 184-191页

作者：王莹宗丰德李峰波 Institute of nonlinear physics Zhejiang Normal University

We predict three-dimensional vortex solitons in a Bose-Einstein condensate under a complex potential,which is the combination of a two-dimensional parabolic trap along the transverse radial direction and a one-dimensional optical-lattice potential along the z axis *** vortex solitons are built in the form of a layer-chain structure made of several fundamental vortices along the optical-lattice *** has not been reported before in the three-dimensional Bose-Einstein *** using a combination of the energy density functional method with direct numerical simulation,we find three-dimensional vortex solitons with topological charges χ=1,χ=2,and χ=***,the macroscopic quantum tunneling and chirp phenomena of the vortex solitons are shown in the ***,the occurrence of macroscopic quantum tunneling provides the possibility for the experimental realization of quantum ***,we successfully manipulate the vortex solitons along the optical lattice *** stability limits for dragging the vortex solitons from an initial fixed position to a prescribed location are further pursued.

关键词： Bose-Einstein condensates Gross-Pitaevskii equation vortex soliton manipulation

Nonlocal Symmetry Reductions for Bosonized Supersymmetric Burgers Equation

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Communications in Theoretical physics 2017年第8期67卷 170-176页

作者：任博林机乐家怡王胜戴天钊 Institute of nonlinear Science Shaoxing University Institute of nonlinear physics Zhejiang Normal University

Based on the bosonization approach, the supersymmetric Burgers(SB) system is transformed to a coupled bosonic system. By solving the bosonized SB(BSB) equation, the difficulties caused by the anticommutative fermionic field of the SB equation can be avoided. The nonlocal symmetry for the BSB equation is obtained by the truncated Painlev′e method. By introducing multiple new fields, the finite symmetry transformation for the BSB equation is derived by solving the first Lie's principle of the prolonged systems. Some group invariant solutions are obtained with the similarity reductions related by the nonlocal symmetry.

关键词： supersymmetric burgers equation nonlocal symmetry symmetry reduction

Exact Solutions of(2+1)-Dimensional HNLS Equation

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Communications in Theoretical physics 2010年第9期54卷 401-406页

作者：郭爱林林机 Instutite of nonlinear physics Zhejiang Normal University

In this paper, we use the classical Lie group symmetry method to get the Lie point symmetries of the （2＋1）-dimensional hyperbolic nonlinear Schr6dinger （HNLS） equation and reduce the （2＋1）-dimensional HNLS equation to some （1 ＋ 1 ）-dimensional partial differential systems. Finally, many exact travelling solutions of the （2＋1）-dimensional HNLS equation are obtained by the classical Lie symmetry reduced method.

关键词： (2+1)-dimensional HNLS equation classical Lie group approach the symmetry reduced method,exact solution

Dynamics and Manipulation for Gap Solitons in Bose-Einstein Condensates under Optical Lattice and Harmonic Potentials

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Communications in Theoretical physics 2011年第8期56卷 273-280页

作者：宗丰德黎菁宋昌盛 Institute of nonlinear physics Zhejiang Normal University

By means of an extended variational approach,we study dynamics for gap solitons in a repulsive interactionBose-Einstein condensate under both a harmonic and an optical lattice *** simplified analytic theorygives the critical strength ratio of harmonic to optical lattice necessary to support multiple stable lattice sites for ***,we use numerical experiments to guide and manipulate the gap solitons to an arbitrary positionvia a time-dependent *** predictions of the extended variational approach are reasonably close to results ofthe *** particular,the variational model helps capture the composition relationship between the variationsof chirp and amplitude.

关键词： Bose-Einstein condensate Gross-Pitaevskii equations extended variational approach gap soli-tons manipulation

An Analog of Einstein’s General Relativity Emerging from Classical Finite Elasticity Theory:Analytical and Computational Issues

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Communications in Computational physics 2013年第8期14卷 801-818页

作者： C.Cherubini S.Filippi nonlinear physics andmathematicalmodeling lab University Campus Bio-MedicoI-00128Via A.del Portillo 21RomeItaly International Center for Relativistic Astrophysics-I.C.R.A. University of Rome“La Sapienza”I-00185 RomeItaly

The“analogue gravity formalism”,an interdisciplinary theoretical scheme developed in the past for studying several non relativistic classical and quantum systems through effective relativistic curved space-times,is here applied to largely deformable elastic bodies described by the nonlinear theory of solid *** the simplest nonlinear constitutive relation for the elastic material given by a Kirchhoff-St Venant strain-energy density function,it is possible to write for the perturbations an effective space-time metric if the deformation is purely longitudinal and depends on one spatial coordinate *** and numerical studies of the corresponding dynamics are performed in selected cases and physical implications of the results obtained are finally discussed.

关键词： Finite elasticity general relativity analogue gravity finite elements method

Constraining the Generalized and Superfluid Chaplygin Gas Models with the Sandage-Loeb Test

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Chinese physics Letters 2015年第5期32卷 174-177页

作者：朱文涛吴普训余洪伟 Center of nonlinear Science and Department of physics Ningbo University

The Sandage Loeb （SL） test is a direct measurement of the cosmic expansion by probing the redshift drifts of quasi-stellar objects in the ＇redshift desert＇ of 2 〈 z 〈 5. In this work, we investigate its constraints on the unified dark energy and dark matter models including the generalized Chaplygin gas and the superfluid Chaplygin gas. In addition, type Ia supernovae （SNIa） data and the distance ratios derived from the cosmic microwave background radiation and baryon acoustic oscillation observations （CMB/BAO） are also used. We find that the mock SL data gives the tightest constraints on the model parameters and it can help to reduce the parameter regions allowed by the present SNIa＋CMB/BAO by about 75% when all datasets considered are combined. Thus the SL test is a worthy and long awaited measurement to probe effectively the cosmic expanding history and the properties of dark energy.

关键词： CMB BA Constraining the Generalized and Superfluid Chaplygin Gas Models with the Sandage-Loeb Test

Localization of Nonlocal Symmetries and Symmetry Reductions of Burgers Equation

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Communications in Theoretical physics 2017年第5期67卷 467-472页

作者：吴剑文楼森岳俞军 Center for nonlinear Science and Department of physics Ningbo University Institute of nonlinear Science Shaoxing University

The nonlocal symmetries of the Burgers equation are explicitly given by the truncated Painlevé *** auto-B?cklund transformation and group invariant solutions are obtained via the localization procedure for the nonlocal residual symmetries. Furthermore, the interaction solutions of the solition-Kummer waves and the solition-Airy waves are obtained.

关键词： integrable systems Burgers equation nonlocal symmetries interactions among different waves

(2+1)-Dimensional Analytical Solutions of the Combining Cubic-Quintic nonlinear Schrdinger Equation

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Communications in Theoretical physics 2012年第4期57卷 523-529页

作者：郭爱林林机 Institute of nonlinear physics Zhejiang Normal University

We investigate analytical solutions of the(2+1)-dimensional combining cubic-quintic nonlinear Schrdinger(CQNLS) equation by the classical Lie group symmetry *** not only obtain the Lie-point symmetries and some(1+1)-dimensional partial differential systems,but also derive bright solitons,dark solitons,kink or anti-kink solutions and the localized instanton solution.

关键词： classical Lie-group method symmetry reduced equation soliton solution

Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and Type Ia Supernova Data

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Chinese physics Letters 2016年第5期33卷 149-151页

作者：李合昆吴普训余洪伟 Center of nonlinear Science and Department of physics Ningbo University

We use the latest baryon acoustic oscillation and Union 2.1 type Ia supernova data to test the cosmic opacity between different redshift regions without assuming any cosmological models. It is found that the universe may be opaque between the redshift regions 0.35 0.44, 0.44 0.57 and 0.6-0.73 since the best fit values of cosmic opacity in these regions are positive, while a transparent universe is favored in the redshift region 0.57-0.63. However, in general, a transparent universe is still consistent with observations at the lo confidence level.

关键词： of in Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and Type Ia Supernova Data with that is