6,882 research outputs found
Role of isospin physics in supernova matter and neutron stars
We investigate the liquid-gas phase transition of hot protoneutron stars
shortly after their birth following supernova explosion and the composition and
structure of hyperon-rich (proto)neutron stars within a relativistic mean-field
model where the nuclear symmetry energy has been constrained from the measured
neutron skin thickness of finite nuclei. Light clusters are abundantly formed
with increasing temperature well inside the neutrino-sphere for an uniform
supernova matter. Liquid-gas phase transition is found to suppress the cluster
yield within the coexistence phase as well as decrease considerably the
neutron-proton asymmetry over a wide density range. We find symmetry energy has
a modest effect on the boundaries and the critical temperature for the
liquid-gas phase transition, and the composition depends more sensitively on
the number of trapped neutrinos and temperature of the protoneutron star. The
influence of hyperons in the dense interior of stars makes the overall equation
of state soft. However, neutrino trapping distinctly delays the appearance of
hyperons due to abundance of electrons. We also find that a softer symmetry
energy further makes the onset of hyperon less favorable. The resulting
structures of the (proto)neutron stars with hyperons and with liquid-gas phase
transition are discussed.Comment: 11 pages, 7 figures, RevTe
Teleological Essentialism: Generalized
Natural/social kind essentialism is the view that natural kind categories, both living and non-living natural kinds, as well as social kinds (e.g., race, gender), are essentialized. On this view, artifactual kinds are not essentialized. Our view—teleological essentialism—is that a broad range of categories are essentialized in terms of teleology, including artifacts. Utilizing the same kinds of experiments typically used to provide evidence of essentialist thinking—involving superficial change (study 1), transformation of insides (study 2) and inferences about offspring (study 3)—we find support for the view that a broad range of categories—living natural kinds, non-living natural kinds and artifactual kinds—are essentialized in terms of teleology. Study 4 tests a unique prediction of teleological essentialism and also provides evidence that people make inferences about purposes which in turn guide categorization judgments
Nonperturbative analysis of coupled quantum dots in a phonon bath
Transport through coupled quantum dots in a phonon bath is studied using the
recently developed real-time renormalization-group method. Thereby, the problem
can be treated beyond perturbation theory regarding the complete interaction. A
reliable solution for the stationary tunnel current is obtained for the case of
moderately strong couplings of the dots to the leads and to the phonon bath.
Any other parameter is arbitrary, and the complete electron-phonon interaction
is taken into account. Experimental results are quantitatively reproduced by
taking into account a finite extension of the wavefunctions within the dots.
Its dependence on the energy difference between the dots is derived.Comment: 8 pages, 6 figure
Capital Mobility for Developing Countries May Not Be So High
International capital flows to developing countries have taken on considerable policy importance in recent years. There is disagreement, however, about whether financial capital mobility has become so high that developing countries have little ability to sterilize capital flows. This paper reviews several popular methods of estimating the degree of capital mobility for developing countries and shows that they are subject to potentially important upward biases due to inappropriate assumptions concerning the roles of domestic inflation and sterilization. Corrections for these factors can cut estimates of capital mobility by one half or more.sterilization; capital mobility; developing countries
Strangeness in Compact Stars and Signal of Deconfinement
Phase transitions in compact stars are discussed including hyperonization,
deconfinement and crystalline phases. Reasons why kaon condensation is unlikely
is reviewed. Particular emphasis is placed on the evolution of internal
structure with spin-down of pulsars. A signature of a first order phase
transition in the timing structure of pulsars which is strong and easy to
measure, is identified.Comment: 17 pages, 15 figures, Latex. (Invited Talk at the International
Symposium on ``Strangeness In Quark Matter 1997'', Thera (Santorini), Hellas,
April 14-18, 1997, To be published in Journal of Physics G (Organizers: A
Panagiotou and J. Madsen
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