6,380 research outputs found
Effect of Resonant Continuum on Pairing Correlations in the Relativistic Approach
A proper treatment of the resonant continuum is to take account of not only
the energy of the resonant state, but also its width. The effect of the
resonant states on pairing correlations is presented based on the relativistic
mean field theory plus Bardeen-Cooper-Schrieffer(BCS) approximation with a
constant pairing strength. The study is performed in an effective Lagrangian
with the parameter set NL3 for neutron rich even-even Ni isotopes. The results
show that the contribution of the proper treatment of the resonant continuum to
pairing correlations for those nuclei close to neutron drip line is important.
The pairing gaps, Fermi energies, pairing correlation energies, and binding
energies are considerably affected with a proper consideration of the width of
resonant states. The problem of an unphysical particle gas, which may appear in
the calculation of the traditional mean field plus BCS method for nuclei in the
vicinity of drip line could be well overcome when the pairing correlation is
performed by using the resonant states instead of the discretized states in the
continuum.Comment: 19 pages, 8 Postscript figur
Quantization of Black Holes
We show that black holes can be quantized in an intuitive and elegant way
with results in agreement with conventional knowledge of black holes by using
Bohr's idea of quantizing the motion of an electron inside the atom in quantum
mechanics. We find that properties of black holes can be also derived from an
Ansatz of quantized entropy \Delta S=4\pi k {\Delta R / \lambdabar}, which
was suggested in a previous work to unify the black hole entropy formula and
Verlinde's conjecture to explain gravity as an entropic force. Such an Ansatz
also explains gravity as an entropic force from quantum effect. This suggests a
way to unify gravity with quantum theory. Several interesting and surprising
results of black holes are given from which we predict the existence of
primordial black holes ranging from Planck scale both in size and energy to big
ones in size but with low energy behaviors.Comment: Latex 7 pages, no figure
Composing Distributed Data-intensive Web Services Using a Flexible Memetic Algorithm
Web Service Composition (WSC) is a particularly promising application of Web
services, where multiple individual services with specific functionalities are
composed to accomplish a more complex task, which must fulfil functional
requirements and optimise Quality of Service (QoS) attributes, simultaneously.
Additionally, large quantities of data, produced by technological advances,
need to be exchanged between services. Data-intensive Web services, which
manipulate and deal with those data, are of great interest to implement
data-intensive processes, such as distributed Data-intensive Web Service
Composition (DWSC). Researchers have proposed Evolutionary Computing (EC)
fully-automated WSC techniques that meet all the above factors. Some of these
works employed Memetic Algorithms (MAs) to enhance the performance of EC
through increasing its exploitation ability of in searching neighbourhood area
of a solution. However, those works are not efficient or effective. This paper
proposes an MA-based approach to solving the problem of distributed DWSC in an
effective and efficient manner. In particular, we develop an MA that hybridises
EC with a flexible local search technique incorporating distance of services.
An evaluation using benchmark datasets is carried out, comparing existing
state-of-the-art methods. Results show that our proposed method has the highest
quality and an acceptable execution time overall.Comment: arXiv admin note: text overlap with arXiv:1901.0556
CP violation in Higgs decays
We study CP violation in fermion pair decays of Higgs boson. We idenfy some
CP odd observables related to the tree level decay amplitude. We find that a
few thousand Higgs boson decay events can already provide important information
about CP violation. If the Higgs boson is produced, such an analysis could be
carried out at the SSC, LHC and NLC.Comment: 9 pages, Revtex, UM-P-93/11, OZ-93/
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