15,234 research outputs found
Quantum-mechanical effects in a linear time-dependent potential
The solution of the time-dependent Schr\"odinger equation is discussed for a
particle confined in half-space with a linear potential in the
following situations: (a) sudden removal of the wall and switching on the
linear potential at , (b) sudden removal of the wall and
the potential and (c) sudden removal of the potential. A brief discussion of
the quantum statistic is presented.Comment: 9 pages, 6 figure
On the stability of Einstein static universe at background level in massive bigravity
We study the static cosmological solutions and their stability at background
level in the framework of massive bigravity theory with
Friedmann-Robertson-Walker (FRW) metrics. By the modification proposed in the
cosmological equations subject to a perfect fluid we obtain new solutions
interpreted as the Einstein static universe. It turns out that the
non-vanishing size of initial scale factor of Einstein static universe depends
on the non-vanishing three-dimensional spatial curvature of FRW metrics and
also the graviton's mass. By dynamical system approach and numerical analysis,
we find that the extracted solutions for closed and open universes can be
stable for some viable ranges of equation of state parameter, viable values of
fraction of two scale factors, and viable values of graviton's mass obeying the
hierarchy which is more cosmologically motivated.Comment: 14 pages, 8 figures, 5 tables, major revisio
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Service attribute importance and strategic planning: An empirical study
There is growing evidence that attribute importance is a function of attribute performance. Several studies reported that service quality attributes fall into three categories: basic, performance, and excitement. Thus, the identification of attribute importance is significantly important as a key to customer satisfaction evaluation and other behavioural intentions. According to customer behaviour literature, attribute importance can be measured in two ways: (1) self-stated importance, and (2) statistically inferred importance. The article evaluates two methods according to their impact on overall customer satisfaction measurement and, managerial implementation. A case study is conducted on the telecommunication industry for analysis
Vacuum spherically symmetric solutions in gravity
Spherically symmetric static vacuum solutions have been built in
models of gravity theory. We apply some conditions on the metric components;
then the new vacuum spherically symmetric solutions are obtained. Also, by
extracting metric coefficients we determine the analytical form of .Comment: 8 pages,typos corrected, Refs. adde
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