Results 271 to 280 of about 66,116 (307)

Noncommuting contractions of oscillators with constant force

Journal of Physics A: Mathematical and General, 2006
We find two noncommuting contractions of the Lie algebras u(N) and gl(N, ), realized as the symmetry algebras of N-dimensional isotropic harmonic and repulsive oscillators of spring constant k ∈ , with a constant force of magnitude f . The contraction limit to the symmetry algebra of the Ndimensional free system is (k, f ) → (0, 0). We take two paths
Jamil Daboul, Kurt Bernardo Wolf
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Oscillating metrics and the cosmological constant

AIP Conference Proceedings, 2001
Oscillating metric solutions are found in theories with higher powers of curvature in the action. Their consideration is motivated by the cosmological constant problem.
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Analysis and synthesis of piecewise-constant oscillators

The 2004 47th Midwest Symposium on Circuits and Systems, 2004. MWSCAS '04., 2004
In this paper, piecewise constant systems whose vector fields are piecewise constant, namely that the righthand side of the state equation is piecewise constant, are considered. Because of piecewise-constant characteristics, the states move proportionally to time except at the moment that vector fields switches, and the trajectories are piecewise ...
T. Tsubone, N. Kambayashi
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An Improvement in Constant-Frequency Oscillators

Proceedings of the IRE, 1939
A simple oscillator circuit is described in which, by means of impedance transformation, the tube impedances are made small relative to those of the tuned circuit. As a result all frequency variations inherent in the tube are reduced by a factor of ten, or more.
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Coupling constant analyticity for the anharmonic oscillator

Annals of Physics, 1970
Abstract We study the analytic properties of the singular perturbation theory for p2 + x2 + βx4. We prove rigorously several of the properties of the energy levels, previously found by C. Bender and T. T. Wu using methods of unknown validity. In particular: (a) En(β) has a “global” third-order branch point at β = 0, i.e., any path of continuation ...
Barry Simon, A Dicke
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On the Existence of an Absolute Constant Concerning "Flat" Oscillators

American Journal of Mathematics, 1957
For large positive t, let co(t) be a positive continuous function correspondinig to which the differential equation (*) x"'+ W2 (t)x 0 has the following property: x'(t) -* 0, as t -* oo, holds for the derivative of every solutioni x(t) of (*). Then (*) will be called flat (all of its solutions "flatten out"; still, they can be "wobbly" and "large," as ...
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On some properties of harmonic oscillator on spaces of constant curvature

Reports on Mathematical Physics, 2002
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Rañada, Manuel F., Santander, Mariano
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On Multimode Oscillators with Constant Time Delay

Proceedings of the IRE, 1957
Special emphasis is paid to narrow-band systems with a small number of modes, and to high switching speed. Sufficient stability conditions presented have been derived by use of a first-order Taylor approximation, which substantially reduces algebraic complexity. The system may deviate considerably from quasi-linearity.
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Plasma oscillations in a constant electric field

Plasma Physics, 1969
Summary: The dispersion relation for longitudinal oscillations has been derived for a plasma in a uniform applied electric field for the case where the collision integral can be replaced by a Fokker-Planck term with distinct and energy-dependent relaxation times for momentum and energy.
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Cosmological consequences of high-frequency oscillations of Newton’s constant

Physical Review Letters, 1991
We show that high-frequency, small-amplitude oscillations of Newton's constant {ital G} can dramatically alter cosmology even if the frequency is very high compared to the expansion rate. For example, it is possible to have a spatially flat universe in which dynamical tests of {Omega}==(matter density)/(critical density)---tests which attempt to ...
, Accetta, , Steinhardt
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