Based on the framework of Kaniadakis’statistics and its related kinetic theory,the Jeans instability for selfgravitational systems in the background of Eddington-inspired Born-Infield(EiBI)gravity is revisited.A disp...Based on the framework of Kaniadakis’statistics and its related kinetic theory,the Jeans instability for selfgravitational systems in the background of Eddington-inspired Born-Infield(EiBI)gravity is revisited.A dispersion relation generalizing the Jeans modes is derived by modifying the Maxwellian distribution to a family of power law distributions parameterized by the κ parameter.It is established that theκ-deformed Kaniadakis distribution has significant effects on the Jeans modes of the collisionless EiBI-gravitational systems.And as expected,in the limitation κ→0,the corresponding results for Maxwellian case are recovered.The related result in the present work is valuable for the investigations involving the fields of astrophysics such as neutron stars,accretion disks,and relevant plasma physics,etc.展开更多
We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum system.The master equation that governs their evolution is derived by tracing over the degree of f...We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum system.The master equation that governs their evolution is derived by tracing over the degree of freedom of the field.With this,we compare the entanglement dynamics of the two atoms moving with different trajectories inκ-deformed and Minkowski spacetimes.Notably,when the environment-induced interatomic interaction does not exist,the entanglement dynamics of two static atoms inκ-deformed spacetime are reduced to that in Minkowski spacetime in the case that the spacetime deformation parameterκis sufficiently large as theoretically predicted.However,if the atoms undergo relativistic motion,regardless of whether inertial or non-inertial,their entanglement dynamics inκ-deformed spacetime behave differently from that in Minkowski spacetime even whenκis large.We investigate various types of entanglement behavior,such as decay and generation,and discuss how different relativistic motions,such as uniform motion in a straight line and circular motion,amplify the differences in the entanglement dynamics between theκ-deformed and Minkowski spacetime cases.In addition,when the environment-induced interatomic interaction is considered,we find that it may also enhance the differences in the entanglement dynamics between these two spacetimes.Thus,in principle,one can tell whether she/he is inκ-deformed or Minkowski spacetime by checking the entanglement behavior between two atoms in certain circumstances.展开更多
An improved constrained(IC)steering law for single gimbal control moment gyros(SGCMGs)with deformed pyramid configuration(DPC)is proposed,First of all,the original system with five pyramid configuration(FPC)whose two ...An improved constrained(IC)steering law for single gimbal control moment gyros(SGCMGs)with deformed pyramid configuration(DPC)is proposed,First of all,the original system with five pyramid configuration(FPC)whose two adjacent gyros are in failure state is reconfigured as a degraded system with DPC.Then,the singular angular momentum hypersurfaces of the original and the degraded systems are plotted via the singular angular momentum equa-tion of SGCMGs.Based on singular surfaces,the differences between FPC and DPC in singularity and momentum envelope are obtained directly,which provide an important reference for steering law design of DPC.Finally,an IC steering law is designed and applied to DPC.The simulation results demonstrate that the IC steering law has advantages in simplicity of calculation,avoidance of singularity and exactness of output torque,which endow the degraded system with fine controllability in a restricted workspace.展开更多
This paper proves the following results: let X be a continuum, let k, m ∈ N, and let B ∈ C m (X), consider the continuous surjection f k : C k (X) → C k (X). We define the mapping B : C k (X) → C k+m (X): by B (A)...This paper proves the following results: let X be a continuum, let k, m ∈ N, and let B ∈ C m (X), consider the continuous surjection f k : C k (X) → C k (X). We define the mapping B : C k (X) → C k+m (X): by B (A) = f k (A) B. Then following assertions are equivalent: (1) The hyperspace C k (X) is g-contractible; (2) For each m ∈ N and for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (3) For each m ∈ N there exists B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X); (4) There exists m ∈ N such that for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (5) There exist m ∈ N and B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X).展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11763006 and 11863004)the Fund from the Jiangxi Provincial Key Laboratory of Fusion and Information Control(Grant No.20171BCD40005).
文摘Based on the framework of Kaniadakis’statistics and its related kinetic theory,the Jeans instability for selfgravitational systems in the background of Eddington-inspired Born-Infield(EiBI)gravity is revisited.A dispersion relation generalizing the Jeans modes is derived by modifying the Maxwellian distribution to a family of power law distributions parameterized by the κ parameter.It is established that theκ-deformed Kaniadakis distribution has significant effects on the Jeans modes of the collisionless EiBI-gravitational systems.And as expected,in the limitation κ→0,the corresponding results for Maxwellian case are recovered.The related result in the present work is valuable for the investigations involving the fields of astrophysics such as neutron stars,accretion disks,and relevant plasma physics,etc.
基金supported by the Key Program of the National Natural Science Foundation of China(NSFC)(Grant No.12035005)supported by NSFC(Grant No.12065016)+2 种基金supported by NSFC(Grant No.11905218)the Discipline-Team of Liupanshui Normal University of China(Grant No.LPSSY2023XKTD11)the Scientific Research Start-Up Funds of Hangzhou Normal University(Grant No.4245C50224204016)。
文摘We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum system.The master equation that governs their evolution is derived by tracing over the degree of freedom of the field.With this,we compare the entanglement dynamics of the two atoms moving with different trajectories inκ-deformed and Minkowski spacetimes.Notably,when the environment-induced interatomic interaction does not exist,the entanglement dynamics of two static atoms inκ-deformed spacetime are reduced to that in Minkowski spacetime in the case that the spacetime deformation parameterκis sufficiently large as theoretically predicted.However,if the atoms undergo relativistic motion,regardless of whether inertial or non-inertial,their entanglement dynamics inκ-deformed spacetime behave differently from that in Minkowski spacetime even whenκis large.We investigate various types of entanglement behavior,such as decay and generation,and discuss how different relativistic motions,such as uniform motion in a straight line and circular motion,amplify the differences in the entanglement dynamics between theκ-deformed and Minkowski spacetime cases.In addition,when the environment-induced interatomic interaction is considered,we find that it may also enhance the differences in the entanglement dynamics between these two spacetimes.Thus,in principle,one can tell whether she/he is inκ-deformed or Minkowski spacetime by checking the entanglement behavior between two atoms in certain circumstances.
基金supported by the National Natural Science Foundation of China(10372011)
文摘An improved constrained(IC)steering law for single gimbal control moment gyros(SGCMGs)with deformed pyramid configuration(DPC)is proposed,First of all,the original system with five pyramid configuration(FPC)whose two adjacent gyros are in failure state is reconfigured as a degraded system with DPC.Then,the singular angular momentum hypersurfaces of the original and the degraded systems are plotted via the singular angular momentum equa-tion of SGCMGs.Based on singular surfaces,the differences between FPC and DPC in singularity and momentum envelope are obtained directly,which provide an important reference for steering law design of DPC.Finally,an IC steering law is designed and applied to DPC.The simulation results demonstrate that the IC steering law has advantages in simplicity of calculation,avoidance of singularity and exactness of output torque,which endow the degraded system with fine controllability in a restricted workspace.
基金Supported by the Department of Education Sichuan Province Foundation for Science Research(2006C041)Supported by the Anhui Provincial Foundation for Young Talents in College(2010SQRL158)
文摘This paper proves the following results: let X be a continuum, let k, m ∈ N, and let B ∈ C m (X), consider the continuous surjection f k : C k (X) → C k (X). We define the mapping B : C k (X) → C k+m (X): by B (A) = f k (A) B. Then following assertions are equivalent: (1) The hyperspace C k (X) is g-contractible; (2) For each m ∈ N and for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (3) For each m ∈ N there exists B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X); (4) There exists m ∈ N such that for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (5) There exist m ∈ N and B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X).
