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991.
We find the solutions of the Dirac equation for two plane waves (laser beams) and we determine the modified Compton formula for the scattering of two photons on an electron. The practical meaning of the two laser beams is, that two laser beams impinging on a target which is constituted from material in the form a foam, can replace 100–200 laser beams impinging on a normal target and it means that the nuclear fusion with two laser beams is realistic in combination with the thermonuclear reactor such as ITER.  相似文献   
992.
This article is concerned with the numerical solution of multiobjective control problems associated with nonlinear partial differential equations and more precisely the Burgers equation. For this kind of problems, we look for the Nash equilibrium, which is the solution to a noncooperative game. To compute the solution of the problem, we use a combination of finite-difference methods for the time discretization, finite-element methods for the space discretization, and a quasi-Newton BFGS algorithm for the iterative solution of the discrete control problem. Finally, we apply the above methodology to the solution of several tests problems. To be able to compare our results with existing results in the literature, we discuss first a single-objective control problem, already investigated by other authors. Finally, we discuss the multiobjective case.  相似文献   
993.
We examine the dynamic and geometric phases of the electron in quantum mechanics using Hestenes' spacetime algebra formalism. First the standard dynamic phase formula is translated into the spacetime algebra. We then define new formulas for the dynamic and geometric phases that can be used in Hestenes' formalism.  相似文献   
994.
995.
李固强 《中国物理》2005,14(3):468-471
The divergences at all levels for the statistical entropy of a plane symmetry black hole arising from the massless Dirac field are considered using the brick-wall model. It is shown that if we ignore the usual contribution from the vacuum surrounding the system, then the statistical entropy consists of two parts: one is the linearly divergent term which has the geometric character, the other consists of two logarithmically divergent terms which are not proportional to the surface area of the horizon. The entropy of the Dirac field on extremal plane symmetry spacetime background has higher divergence than usual.  相似文献   
996.
We develop the idea of employing localization systems of Boolean coverings, associated with measurement situations, in order to comprehend structures of quantum observables. In this manner, Boolean domain observables constitute structure sheaves of coordinatization coefficients in the attempt to probe the quantum world. Interpretational aspects of the proposed scheme are discussed with respect to a functorial formulation of information exchange, as well as, quantum logical considerations. Finally, the sheaf theoretical construction suggests an operationally intuitive method to develop differential geometric concepts in the quantum regime.  相似文献   
997.
998.
In this paper a generalization of the classicalRarita–Schwinger equations for spin 3/2 fields to the case of spin fieldswith values in irreducible representation spaces with weight k+1/2 isgiven. It corresponds to the study of serie of first orderconformal invariant operators, which are constructed from twisted Diracoperators. The representation character of polynomial solutions of the equations onflat space and their relations are described in details.  相似文献   
999.
1000.
We consider the linear Stark effect in the MIC–Kepler problem describing the interaction of a charged particle with a Dirac dyon and show that a constant homogeneous electric field completely removes the degeneracy of energy levels with respect to the azimuthal quantum number.  相似文献   
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