8,877 research outputs found
Non-thermal radiation of black hole off canonical typicality
We study the Hawking radiation of black holes by considering the canonical
typicality. For the universe consisting of black holes and their outer part, we
directly obtain a non-thermal radiation spectrum of an arbitrary black hole
from its entropy, which only depends on a few external qualities (known as
hairs), such as mass, charge, and angular momentum. Our result shows that the
spectrum of the non-thermal radiation is independent of the detailed quantum
tunneling dynamics across black hole horizon. We prove that the black hole
information paradox is naturally resolved by taking account the correlation
between black hole and its radiation in our approach.Comment: 5 pages, 1 figure, pulished on Europhysics Letters, comments are
welcome
Properties of the Planetary Caustic Perturbation
Just two of 10 extrasolar planets found by microlensing have been detected by
the planetary caustic despite the higher probability of planet detection
relative to the central caustic which has been responsible for four extrasolar
planet detections. This is because the perturbations induced by the planetary
caustic are unpredictable, thus making it difficult to carry out strategic
observations. However, if future high-cadence monitoring surveys are conducted,
the majority of planetary caustic events including the events by free-floating
planets and wide-separation planets would be detected. Hence, understanding the
planetary caustic perturbations becomes important. In this paper, we
investigate in detail the pattern of the planetary caustic perturbations. From
this study, we find three properties of the planetary caustic perturbations.
First, planetary systems with the same star-planet separation (s) basically
produce perturbations of constant strength regardless of the planet/star mass
ratio (q), but the duration of each perturbation scales with sqrt{q}. Second,
close planetary systems with the same separation produce essentially the same
negative perturbations between two triangular-shaped caustics regardless of q,
but the duration of the perturbations scales with sqrt{q}. Third, the positive
perturbations for planetary systems with the same mass ratio become stronger as
the caustic shrinks with the increasing |log s|, while the negative
perturbations become weaker. We estimate the degeneracy in the determination of
q that occurs in planetary caustic events. From this, we find that the mass
ratio can be more precisely determined as q increases and |log s| decreases. We
also find that the degeneracy range of events for which the source star passes
close to the planetary caustic is usually very narrow, and thus it would not
significantly affect the determination of q.Comment: 5 pages, 3 figures, 2 tables, accepted in MNRA
ANALYSIS OF THE IMPACT OF ENVIRONMENTAL DIFFERENCES IN THE SPATIAL DISTRIBUTION AND EVOLUTION OF TRADITIONAL VILLAGES ON THE PSYCHOLOGICAL ANXIETY OF TOURISM CONSUMERS
ANALYSIS OF THE IMPACT OF ENVIRONMENTAL DIFFERENCES IN THE SPATIAL DISTRIBUTION AND EVOLUTION OF TRADITIONAL VILLAGES ON THE PSYCHOLOGICAL ANXIETY OF TOURISM CONSUMERS
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