14,259 research outputs found
On the Completeness of the Quasinormal Modes of the Poeschl-Teller Potential
The completeness of the quasinormal modes of the wave equation with
Poeschl-Teller potential is investigated. A main result is that after a large
enough time , the solutions of this equation corresponding to
-data with compact support can be expanded uniformly in time with
respect to the quasinormal modes, thereby leading to absolutely convergent
series. Explicit estimates for depending on both the support of the data
and the point of observation are given. For the particular case of an ``early''
time and zero distance between the support of the data and observational point,
it is shown that the corresponding series is not absolutely convergent, and
hence that there is no associated sum which is independent of the order of
summation.Comment: 22 pages, 2 figures, submitted to Comm. Math. Phy
Results on the spectrum of R-Modes of slowly rotating relativistic stars
The paper considers the spectrum of axial perturbations of slowly uniformly
rotating general relativistic stars in the framework of Y. Kojima. In a first
step towards a full analysis only the evolution equations are treated but not
the constraint. Then it is found that the system is unstable due to a continuum
of non real eigenvalues. In addition the resolvent of the associated generator
of time evolution is found to have a special structure which was discussed in a
previous paper. From this structure it follows the occurrence of a continuous
part in the spectrum of oscillations at least if the system is restricted to a
finite space as is done in most numerical investigations. Finally, it can be
seen that higher order corrections in the rotation frequency can qualitatively
influence the spectrum of the oscillations. As a consequence different
descriptions of the star which are equivalent to first order could lead to
different results with respect to the stability of the star
Conceptual design and feasibility evaluation model of a 10 to the 8th power bit oligatomic mass memory. Volume 2: Feasibility evaluation model
The partially populated oligatomic mass memory feasibility model is described and evaluated. A system was desired to verify the feasibility of the oligatomic (mirror) memory approach as applicable to large scale solid state mass memories
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