The geometric formulation of motion of the first-order linear homogenous scleronomous nonholonomic system subjected to active forces is studied with the non- holonomic mapping theory. The quasi-Newton law, the quasi-m...The geometric formulation of motion of the first-order linear homogenous scleronomous nonholonomic system subjected to active forces is studied with the non- holonomic mapping theory. The quasi-Newton law, the quasi-momentum theorem, and the second kind Lagrange equation of dynamical systems are obtained in the Riemann- Cartan configuration spaces. By the nonholonomic mapping, a Euclidean configuration space or a Riemann configuration space of a dynamical system can be mapped into a Riemann-Cartan configuration space with torsion. The differential equations of motion of the dynamical system can be obtained in its Riemann-Cartan configuration space by the quasi-Newton law or the quasi-momentum theorem. For a constrained system~ the differential equations of motion in its Riemann-Cartan configuration space may be sim- pler than the equations in its Euclidean configuration space or its Riemann configuration space. Therefore, the nonholonomic mapping theory can solve some constrained prob- lems, which are difficult to be solved by the traditional analytical mechanics method. Three examples are given to illustrate the effectiveness of the method.展开更多
We consider a Hamiltonian of a system of two fermions on a three-dimensional lattice Z<sup>3</sup> with special potential <img alt="" src="Edit_56564354-6d65-4104-9126-d4657fa750af.png&qu...We consider a Hamiltonian of a system of two fermions on a three-dimensional lattice Z<sup>3</sup> with special potential <img alt="" src="Edit_56564354-6d65-4104-9126-d4657fa750af.png" />. The corresponding Shrödinger operator <em>H</em>(<strong>k</strong>) of the system has an invariant subspac <span style="white-space:nowrap;"><span><em>L</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(T<sup>3</sup>)</span> , where we study the eigenvalues and eigenfunctions of its restriction <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub></span><span style="white-space:nowrap;">(<strong>k</strong>)</span>. Moreover, there are shown that <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(<em>k</em><sub>1</sub>, <em>k</em><sub>2</sub>, π)</span> has also infinitely many invariant subspaces <img alt="" src="Edit_4955ffad-4b18-434a-8c99-ff14779f2812.bmp" />, where the eigenvalues and eigenfunctions of eigenvalue problem <img alt="" src="Edit_01b218d2-fa3e-4f39-bc2d-ce736205db93.bmp" />are explicitly found.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.11772144,11572145,11472124,11572034,and 11202090)the Science and Technology Research Project of Liaoning Province(No.L2013005)+1 种基金the China Postdoctoral Science Foundation(No.2014M560203)the Natural Science Foundation of Guangdong Provience(No.2015A030310127)
文摘The geometric formulation of motion of the first-order linear homogenous scleronomous nonholonomic system subjected to active forces is studied with the non- holonomic mapping theory. The quasi-Newton law, the quasi-momentum theorem, and the second kind Lagrange equation of dynamical systems are obtained in the Riemann- Cartan configuration spaces. By the nonholonomic mapping, a Euclidean configuration space or a Riemann configuration space of a dynamical system can be mapped into a Riemann-Cartan configuration space with torsion. The differential equations of motion of the dynamical system can be obtained in its Riemann-Cartan configuration space by the quasi-Newton law or the quasi-momentum theorem. For a constrained system~ the differential equations of motion in its Riemann-Cartan configuration space may be sim- pler than the equations in its Euclidean configuration space or its Riemann configuration space. Therefore, the nonholonomic mapping theory can solve some constrained prob- lems, which are difficult to be solved by the traditional analytical mechanics method. Three examples are given to illustrate the effectiveness of the method.
文摘We consider a Hamiltonian of a system of two fermions on a three-dimensional lattice Z<sup>3</sup> with special potential <img alt="" src="Edit_56564354-6d65-4104-9126-d4657fa750af.png" />. The corresponding Shrödinger operator <em>H</em>(<strong>k</strong>) of the system has an invariant subspac <span style="white-space:nowrap;"><span><em>L</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(T<sup>3</sup>)</span> , where we study the eigenvalues and eigenfunctions of its restriction <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub></span><span style="white-space:nowrap;">(<strong>k</strong>)</span>. Moreover, there are shown that <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(<em>k</em><sub>1</sub>, <em>k</em><sub>2</sub>, π)</span> has also infinitely many invariant subspaces <img alt="" src="Edit_4955ffad-4b18-434a-8c99-ff14779f2812.bmp" />, where the eigenvalues and eigenfunctions of eigenvalue problem <img alt="" src="Edit_01b218d2-fa3e-4f39-bc2d-ce736205db93.bmp" />are explicitly found.