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Generalized Canonical Transformations for Fractional Birkhoffian Systems 被引量:1
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作者 ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第4期499-506,共8页
This paper presents fractional generalized canonical transformations for fractional Birkhoffian systems within Caputo derivatives.Firstly,based on fractional Pfaff-Birkhoff principle within Caputo derivatives,fraction... This paper presents fractional generalized canonical transformations for fractional Birkhoffian systems within Caputo derivatives.Firstly,based on fractional Pfaff-Birkhoff principle within Caputo derivatives,fractional Birkhoff’s equations are derived and the basic identity of constructing generalized canonical transformations is proposed.Secondly,according to the fact that the generating functions contain new and old variables,four kinds of generating functions of the fractional Birkhoffian system are proposed,and four basic forms of fractional generalized canonical transformations are deduced.Then,fractional canonical transformations for fractional Hamiltonian system are given.Some interesting examples are finally listed. 展开更多
关键词 fractional Birkhoffian system generalized canonical transformation fractional Pfaff-Birkhoff principle generating function
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Quantum Systems Connected by a Time-Dependent Canonical Transformation
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作者 Kyu Hwang Yeon Jeong Ryeol Choi ZHANG Shou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期416-420,共5页
We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent ... We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent Hamiltonian system. The quantum unitary operator relevant to classical canonical transformation between the two systems are obtained through rigorous evaluation. With the aid of the unitary operator, we have derived quantum states of the time-dependent Hamiltonian system through transforming the quantum states of the conservative system. The invariant operators of the two systems are presented and the relation between them are addressed. We showed that there exist numerous Hamiltonians, which gives the same classical equation of motion. Though it is impossible to distinguish the systems described by these Hamiltonians within the realm of classical mechanics, they can be distinguishable quantum mechanically. 展开更多
关键词 canonical transformation innumerable kind of Hamiltonians canonical quantization invariant operator unitary transformation
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GENERALIZED CANONICAL TRANSFORMATION AND SYMPLECTIC ALGORITHM OF THE AUTONOMOUS BIRKHOFFIAN SYSTEMS
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作者 张兴武 武际可 +1 位作者 朱海平 黄克服 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第9期1029-1034,共6页
The Birkhoff systems are the generalization of the Hamiltonian systems. Generalized canonical transformations are studied. The symplectic algorithm of the Hamiltonian systems is extended into that of the Birkhofflan s... The Birkhoff systems are the generalization of the Hamiltonian systems. Generalized canonical transformations are studied. The symplectic algorithm of the Hamiltonian systems is extended into that of the Birkhofflan systems. Symplectic differential scheme of autonomous Birkhoffian systems vas structured and discussed by introducing the Kailey Transformation. 展开更多
关键词 Birkhoffian system sympletic algorithm canonical transformation
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From Translation to Linear and Linear Canonical Transformations
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作者 Tan Si Do 《Applied Mathematics》 2022年第6期502-522,共21页
In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called du... In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called dual couple in this work, is valuable for any other dual couple, so that from the known translation operator exp(a&#8706;<sub>x</sub>) one may obtain the explicit form and properties of a category of linear and linear canonical transformations in 2N-phase spaces. Moreover, other forms of LCTs are also obtained in this work as so as the transforms by them of functions by integrations as so as by derivations. In this way, different kinds of LCTs such as Fast Fourier, Fourier, Laplace, Xin Ma and Rhodes, Baker-Campbell-Haussdorf, Bargman transforms are found again. 展开更多
关键词 Dual Operators Fundamental Law of Operator Calculus Newtonian Binomial and Translation Linear and Linear canonical Transforms From Fourier to Gauss and LCTs’ Transforms
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ON THE DECOMPOSITION OF COMPLEX VECTOR SPACES AND THE JORDAN CANONICAL FORM OF COMPLEX LINEAR TRANSFORMATIONS
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作者 肖衡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期997-1003,共7页
New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations a... New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations and provide all Jordan basesby which the Jordan canonical form is constructed. Accordingly, they can result in thecelebrated Jordan theorem and the third decomposition theorem of space directly. and,moreover, they can give a new deep insight into the exquisite and subtle structure ofthe Jordan form. The latter indicates that the Jordan canonical form of a complexlinear transformation is an invariant structure associated with double arbitrary. choices. 展开更多
关键词 complex vector space complex linear transformation. decompo-sition theorems. Jordan canonical form
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Classical and Quantum Behavior of Generalized Oscillators in Terms of Linear Canonical Transformations
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作者 Akihiro Ogura 《Journal of Modern Physics》 2016年第15期2205-2218,共14页
The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a lin... The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a linear transformation in position and momentum, and show that the correspondence between classical and quantum transformations is exactly one-to-one. We found that classical canonical transformations are constructed from quantum unitary transformations as long as we are concerned with linear transformations. We also show the relationship between the invariant operator and a linear transformation. 展开更多
关键词 Quantum canonical transformation Linear transformation Generalized Oscillators Invariant Operator
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A GROUP REPRESENTATION OF CANONICAL TRANSFORMATION
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作者 侯碧辉 杨洪波 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第4期345-350,共6页
The mutual relationships between four generating functions F-1(q, Q), F-2(q, P), F-3(p, P), F-4(p, Q) and four kinds of canonical variables q, p, Q, P concerned in Hamilton's canonical transformations, can be got ... The mutual relationships between four generating functions F-1(q, Q), F-2(q, P), F-3(p, P), F-4(p, Q) and four kinds of canonical variables q, p, Q, P concerned in Hamilton's canonical transformations, can be got with linear transformations from seven basic formulae. All of them are Legendre's transformation, which are implemented by 32 matrices of 8 x 8 which are homomorphic to D-4 point group of 8 elements with correspondence of 4:1. Transformations and relationships of four state functions G(P, T), H(P, S), U(V, S), F(V, T) and four variables P, V, T, S in thermodynamics, are just the same Lagendre's transformations with the relationships of canonical transformations. The state functions of thermodynamics are summarily founded on experimental results of macroscope measurements, and Hamilton's canonical transformations are theoretical generalization of classical mechanics. Both group represents are the same, and it is to say, their mathematical frames are the same. This generality indicates the thermodynamical transformation is an example of one-dimensional Hamilton's canonical transformation. 展开更多
关键词 canonical transformations group theory group represent transformation matrix
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Uncertainty Principle for the Quaternion Linear Canonical Transform in Terms of Covariance 被引量:2
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作者 Yanna Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期238-243,共6页
An uncertainty principle(UP),which offers information about a signal and its Fourier transform in the time-frequency plane,is particularly powerful in mathematics,physics and signal processing community.Under the pola... An uncertainty principle(UP),which offers information about a signal and its Fourier transform in the time-frequency plane,is particularly powerful in mathematics,physics and signal processing community.Under the polar coordinate form of quaternion-valued signals,the UP of the two-sided quaternion linear canonical transform(QLCT)is strengthened in terms of covariance.The condition giving rise to the equal relation of the derived result is obtained as well.The novel UP with covariance can be regarded as one in a tighter form related to the QLCT.It states that the product of spreads of a quaternion-valued signal in the spatial domain and the QLCT domain is bounded by a larger lower bound. 展开更多
关键词 uncertainty principle quaternion linear canonical transform quaternion-valued signals COVARIANCE
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Research Progress on Discretization of Linear Canonical Transform
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作者 Yannan Sun Bingzhao Li Ran Tao 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期205-216,共12页
Linear canonical transformation(LCT)is a generalization of the Fourier transform and fractional Fourier transform.The recent research has shown that the LCT is widely used in signal processing and applied mathematics,... Linear canonical transformation(LCT)is a generalization of the Fourier transform and fractional Fourier transform.The recent research has shown that the LCT is widely used in signal processing and applied mathematics,and the discretization of the LCT becomes vital for the applic-ations of LCT.Based on the development of discretization LCT,a review of important research progress and current situation is presented,which can help researchers to further understand the discretization of LCT and can promote its engineering application.Meanwhile,the connection among different discretization algorithms and the future research are given. 展开更多
关键词 linear canonical transform(LCT) discrete linear canonical transform sampling Wign-er-Ville distribution fast algorithm
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Speech Encryption in Linear Canonical Transform Domain Based on Chaotic Dynamic Modulation
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作者 Liyun Xu Tong Zhang Chao Wen 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期295-304,共10页
In order to transmit the speech information safely in the channel,a new speech encryp-tion algorithm in linear canonical transform(LCT)domain based on dynamic modulation of chaot-ic system is proposed.The algorithm fi... In order to transmit the speech information safely in the channel,a new speech encryp-tion algorithm in linear canonical transform(LCT)domain based on dynamic modulation of chaot-ic system is proposed.The algorithm first uses a chaotic system to obtain the number of sampling points of the grouped encrypted signal.Then three chaotic systems are used to modulate the corres-ponding parameters of the LCT,and each group of transform parameters corresponds to a group of encrypted signals.Thus,each group of signals is transformed by LCT with different parameters.Fi-nally,chaotic encryption is performed on the LCT domain spectrum of each group of signals,to realize the overall encryption of the speech signal.The experimental results show that the proposed algorithm is extremely sensitive to the keys and has a larger key space.Compared with the original signal,the waveform and LCT domain spectrum of obtained encrypted signal are distributed more uniformly and have less correlation,which can realize the safe transmission of speech signals. 展开更多
关键词 communication security linear canonical transform transform domain encryption chaotic system
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Heisenberg Uncertainty Principle for n-Dimen-sional Linear Canonical Transforms
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作者 Yonggang Li Chuan Zhang Huafei Sun 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期249-253,共5页
The uncertainty principle proposed by German physicist Heisenberg in 1927 is a basic principle of quantum mechanics and signal processing.Since linear canonical transformation has been widely used in various fields of... The uncertainty principle proposed by German physicist Heisenberg in 1927 is a basic principle of quantum mechanics and signal processing.Since linear canonical transformation has been widely used in various fields of signal processing recently and Heisenberg uncertainty principle has been endowed with new expressive meaning in linear canonical transforms domain,in this manuscript,an improved Heisenberg uncertainty principle is obtained in linear canonical trans-forms domain. 展开更多
关键词 Heisenberg uncertainty principle linear canonical transforms Pitt inequality
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Gradient Transformation of Momentum and Single-Valued Vector Potential in Nonrelativistic Dynamics
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作者 Illia Dubrovskyi 《Journal of Physical Science and Application》 2014年第5期328-332,共5页
A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The "gradient transformation" is an addition of arbitrary general solution ... A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The "gradient transformation" is an addition of arbitrary general solution of the corresponding homogeneous equation that does not change the Lagrange equations. When dynamics is described by momenta and coordinates, this transformation is not the vector potential modification, which does not change expressions for other physical quantities, but a canonical transformation of momentum, which changes expressions for all fimctions of momentum, not changing the Poisson brackets, and, hence, the integrals of motion. The generating function of this transformation must reverse sign under the time-charge reversal. In quantum mechanics the unitary transformation corresponds to this canonical transformation. It also does not change the commutation relations. The phase of this unitary operator also must reverse sign under the time-charge reversal. Examples of necessary vector potentials for some magnetic fields are presented. 展开更多
关键词 Magnetic field vector potential MOMENTUM gradient transformation canonical transformation unitary transformation.
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Canonical Transformations and Poisson Theory for Dynamics with Non-Standard Lagrangians 被引量:1
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作者 ZHU Lin ZHANG Yi 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第2期106-116,共11页
The canonical transformation and Poisson theory of dynamical systems with exponential,power-law,and logarithmic non-standard Lagrangians are studied,respectively.The criterion equations of canonical transformation are... The canonical transformation and Poisson theory of dynamical systems with exponential,power-law,and logarithmic non-standard Lagrangians are studied,respectively.The criterion equations of canonical transformation are established,and four basic forms of canonical transformations are given.The dynamic equations with non-standard Lagrangians admit Lie algebraic structure.From this,we es-tablish the Poisson theory,which makes it possible to find new conservation laws through known conserved quantities.Some examples are put forward to demonstrate the use of the theory and verify its effectiveness. 展开更多
关键词 non-standard Lagrangians dynamical equations canonical transformation Poisson theory
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A function associated with spherically convex sets
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作者 GUO Qi 《苏州科技大学学报(自然科学版)》 CAS 2024年第4期76-83,共8页
This paper introduced a kind of functions associated with spherically convex sets and discussed their basic properties.Finally,it proved the spherical convexity/concavity of these functions in lower dimensional cases,... This paper introduced a kind of functions associated with spherically convex sets and discussed their basic properties.Finally,it proved the spherical convexity/concavity of these functions in lower dimensional cases,which provides useful information for the essential characteristics of these functions determining spherically convex sets.The results obtained here are helpful in setting up a systematic spherical convexity theory. 展开更多
关键词 spherical convexity spherical support function spherical radial function canonical transformation
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A Quantum Dynamical Mode for the Control of Decoherence 被引量:1
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作者 HuangWan-Xia WangQin-Mou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期59-64,共6页
We present a quantum measurement model where the meter is taken to be a squeezed reservoir. life realize decoherence in macroscopic limits using Bogoliubov transformation, and this kind of system-meter coupling has a ... We present a quantum measurement model where the meter is taken to be a squeezed reservoir. life realize decoherence in macroscopic limits using Bogoliubov transformation, and this kind of system-meter coupling has a dramatic influence on decoherence. 展开更多
关键词 coherent states displace operators squeezing operators canonical transformation DECOHERENCE
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Generalized Uncertainty Inequalities on Fisher Information Associated with LCT 被引量:1
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作者 Guanlei Xu Xiaogang Xu Xiaotong Wang 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期217-227,共11页
Uncertainty principle plays an important role in multiple fields such as physics,mathem-atics,signal processing,etc.The linear canonical transform(LCT)has been used widely in optics and information processing and so o... Uncertainty principle plays an important role in multiple fields such as physics,mathem-atics,signal processing,etc.The linear canonical transform(LCT)has been used widely in optics and information processing and so on.In this paper,a few novel uncertainty inequalities on Fisher information associated with linear canonical transform are deduced.These newly deduced uncer-tainty relations not only introduce new physical interpretation in signal processing,but also build the relations between the uncertainty lower bounds and the LCT transform parameters a,b,c and d for the first time,which give us the new ideas for the analysis and potential applications.In addi-tion,these new uncertainty inequalities have sharper and tighter bounds which are the generalized versions of the traditional counterparts.Furthermore,some numeric examples are given to demon-strate the efficiency of these newly deduced uncertainty inequalities. 展开更多
关键词 linear canonical transform(LCT) Fisher information uncertainty principle
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Variable Frequency Harmonic Oscillator in an Electromagnetic Field
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作者 HUANGBo-Wen WANGJing-Shan +1 位作者 GUZhi-Yu QIANShang-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期45-47,共3页
The invariant, propagator, and wavefunction for a variable frequency harmonic oscillator in an electromagnetic field are obtained by making a specific coordinate transformation and by using the method of phase space p... The invariant, propagator, and wavefunction for a variable frequency harmonic oscillator in an electromagnetic field are obtained by making a specific coordinate transformation and by using the method of phase space path integral method. The probability amplitudes for a dissipative harmonic oscillator in the time varying electric field are obtained. 展开更多
关键词 INVARIANT PROPAGATOR canonical transformation phase space path integral variable frequency harmonic oscillator
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A CALCULATION METHOD TO THE PERTURBATION OF A SATELLITE CAUSED BY THE GRAVITATION FIELD OF THE EARTH
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作者 郑文虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第2期163-171,共9页
In this paper, with the application of the Delauney variables, according to the Hamilton equations, the influence on the perturbation of a satellite exerted by the gravitational force of the earth through canonical tr... In this paper, with the application of the Delauney variables, according to the Hamilton equations, the influence on the perturbation of a satellite exerted by the gravitational force of the earth through canonical transformation has been found out. As a result, the equation about how the position and velocity of the satellite vary with time is deduced. 展开更多
关键词 gravitation field Hamilton equation PERTURBATION canonical transformation
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Phase Space Path Integral Method for Problem of Obtaining Propagator of a Particle with a Force Quadratic in Velocity
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作者 GU Zhi-Yu HUANG Bo-Wen QIAN Shang-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期259-261,共3页
This article uses the phase space path integral method to find the propagator for a particle with a force quadratic in velocity. Two specific canonical transformations has been used for this purpose.
关键词 phase space path integral PROPAGATOR canonical transformation
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Exactly Solvable Schrodinger Equation with Hypergeometric Wavefunctions
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作者 J.Morales J.García-Martínez +1 位作者 J.García-Ravelo J.J.Pena 《Journal of Applied Mathematics and Physics》 2015年第11期1454-1471,共18页
In this work, the canonical transformation method is applied to a general second order differential equation (DE) in order to trasform it into a Schr?dinger-like DE. Our proposal is based on an auxiliary function g(x)... In this work, the canonical transformation method is applied to a general second order differential equation (DE) in order to trasform it into a Schr?dinger-like DE. Our proposal is based on an auxiliary function g(x) which determines the transformation needed to find exactly-solvable potentials associated to a known DE. To show the usefulness of the proposed approach, we consider explicitly their application to the hypergeometric DE with the aim to find quantum potentials with hypergeometric wavefunctions. As a result, different potentials are obtained depending on the choice of the auxiliary function;the generalized Scarf, Posh-Teller, Eckart and Rosen-Morse trigonometric and hyperbolic potentials, are derived by selecting g(x) as constant and proportional to the P(x) hypergeometric coefficient. Similarly, the choices g(x)~P(x)/x2 and g(x)~x2/P(x) give rise to a class of exactly-solvable generalized multiparameter exponential-type potentials, which contain as particular cases the Hulthén, Manning-Rosen and Woods-Saxon models, among others. Our proposition is general and can be used with other important DE within the frame of applied matematics and physics. 展开更多
关键词 canonical transformation Schrodinger-Like Equation Hypergeometric DE Exactly-Solvable Potentials
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