Browsing by Author "PEN, UL"

Now showing 1 - 4 of 4

CONFORMAL GRAVITY WITH TORSION
(1991-08-01)
HAN, P
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KAO, WF
;
PEN, UL
;
交大名義發表
;
光電工程學系
We study a conformal effective theory in the presence of the torsion field. A power-law inflationary solution in the constant gauge is obtained in k = 0 Friedman-Robertson-Walker space. If k not-equal 0, a formal result is also presented. Some technique details are discussed and remarked. It appears that the low energy relic from the torsion field deserves more study.
FINITE MATRIX COMPUTATIONS APPLIED TO THE SCATTERING OF A WAVEPACKET IN THE COULOMB POTENTIAL
(1995-02-28)
PEN, UL
;
JIANG, TF
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物理研究所
;
Institute of Physics
We develop a finite dimensional matrix method to treat wavepacket propagation in potential scattering problems. The method is useful for general quantum mechanical problems. The scattering dynamics of a minimum uncertainty wavepacket in the Coulomb potential is presented.
GENERALIZED FRIEDMANN-ROBERTSON-WALKER METRIC AND REDUNDANCY IN THE GENERALIZED EINSTEIN EQUATIONS
(1991-12-15)
KAO, WF
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PEN, UL
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電子物理學系
;
Department of Electrophysics
A nontrivial redundancy relation, due to the differential structure of the gravitational Bianchi identity as well as the symmetry of the Friedmann-Robertson-Walker metric, in the gravitational field equation is clarified. A generalized Friedmann-Robertson-Walker metric is introduced in order to properly define a one-dimensional reduced problem which offers an alternative approach to obtain the gravitational field equations on Friedmann-Robertson-Walker spaces.
STRONG-FIELD EFFECTS ON THE ONE-DIMENSIONAL HYDROGEN-ATOM IN MOMENTUM SPACE
(1992-10-01)
PEN, UL
;
JIANG, TF
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電子物理學系
;
Department of Electrophysics
The time evolution of the ground state of a one-dimensional hydrogen atom in the intense laser pulse is studied directly in momentum space. A finite matrix representation of operators is developed to solve nonperturbatively the time-dependent Schrodinger equation. We find that some numerical limitations in coordinate space of above-threshold ionization (ATI) can be overcome, and clear physical interpretations of the numerical data are possible. Both the ATI and harmonic-generation spectra are obtained. The correlations between these two multiphoton phenomena are discussed.