20 research outputs found
Object Picture of Quasinormal Modes for Stringy Black Holes
We study the quasinormal modes (QNMs) for stringy black holes. By using
numerical calculation, the relations between the QNMs and the parameters of
black holes are minutely shown. For (1+1)-dimensional stringy black hole, the
real part of the quasinormal frequency increases and the imaginary part of the
quasinormal frequency decreases as the mass of the black hole increases.
Furthermore, the dependence of the QNMs on the charge of the black hole and the
flatness parameter is also illustrated. For (1+3)-dimensional stringy black
hole, increasing either the event horizon or the multipole index, the real part
of the quasinormal frequency decreases. The imaginary part of the quasinormal
frequency increases no matter whether the event horizon is increased or the
multipole index is decreased.Comment: 4 pages, 5 figure
Medical Liability: Review of a Whole Year of Judgments of the Civil Court of Rome
Background: Complaints about medical malpractice have increased over time in Italy, as well as other countries around the world. This scenario, perceived by some as a "malpractice crisis", is a subject of debate in health law and medical law. The costs arising from medical liability lawsuits weigh not only on individual professionals but also on the budgets of healthcare facilities, many of which in Italy are supported by public funds. A full understanding of the phenomenon of medical malpractice appears necessary in order to manage this spreading issue and possibly to reduce the health liability costs. Methods: The retrospective review concerned all the judgments drawn up by the Judges of the Civil Court of Rome, XIII Chamber (competent and specialized section for professional liability trials) published between January 2018 and February 2019. Results: The analysis of data concerning the involved parties showed that in 84.6% of the judgments taken into account, one or more health facilities were sued, while in 58.2% of cases, one or more health workers were present among the defendants. When healthcare providers are the only ones to be summoned, it is dentists and aesthetic doctors/plastic surgeons who undergo most of the claims. In the overall period analyzed, the amount paid was 23,489,254.08 EUR with an average of 163,119.82 EUR. Conclusion: The evidence provided by the reported data is a useful tool to understand medical malpractice in Italy, especially with regard to the occurrence of the phenomenon at a legal level, an aspect still hardly mentioned by existing literature
Asymptotic tails of massive scalar fields in a stationary axisymmetric EMDA black hole geometry
The late-time tail behavior of massive scalar fields is studied analytically
in a stationary axisymmetric EMDA black hole geometry. It is shown that the
asymptotic behavior of massive perturbations is dominated by the oscillatory
inverse power-law decaying tail at the intermediate
late times, and by the asymptotic tail at asymptotically
late times. Our result seems to suggest that the intermediate tails and the asymptotically tails
may be quite general features for evolution of massive scalar fields in any
four dimensional asymptotically flat rotating black hole backgrounds.Comment: 6 page
Gravitational quasinormal modes for Kerr Anti-de Sitter black holes
We investigate the quasinormal modes for gravitational perturbations of
rotating black holes in four dimensional Anti-de Sitter (AdS) spacetime. The
study of the quasinormal frequencies related to these modes is relevant to the
AdS/CFT correspondence. Although results have been obtained for Schwarzschild
and Reissner-Nordstrom AdS black holes, quasinormal frequencies of Kerr-AdS
black holes are computed for the first time. We solve the Teukolsky equations
in AdS spacetime, providing a second order and a Pade approximation for the
angular eigenvalues associated to the Teukolsky angular equation. The
transformation theory and the Regge-Wheeler-Zerilli equations for Kerr-AdS are
obtained.Comment: 20 pages, 13 figures, ReVTe
Quasinormal modes of gravitational perturbation around a Schwarzschild black hole surrounded by quintessence
In this paper, the quasinormal modes of gravitational perturbation around a
Schwarzschild black hole surrounded by quintessence were evaluated by using the
third-order WKB approximation. Due to the presence of quintessence, the
gravitational wave damps more slowly
Quasi-normal modes of the scalar hairy black hole
We calculate QNMs of the scalar hairy black hole in the AdS background using
Horowitz-Hubeny method for the potential that is not known in analytical form.
For some black hole parameters we found pure imaginary frequencies. Increasing
of the scalar field mass does not cause the imaginary part to vanish, it
reaches some minimum and then increases, thus in the case under consideration
the infinitely long living modes (quasi-resonances) do not appear.Comment: 17 pages, 17 figures, LaTe
Intermediate Asymptotics of the Kerr Quasinormal Spectrum
We study analytically the quasinormal mode spectrum of near-extremal
(rotating) Kerr black holes. We find an analytic expression for these
black-hole resonances in terms of the black-hole physical parameters: its
Bekenstein-Hawking temperature T_{BH} and its horizon's angular velocity
\Omega, which is valid in the intermediate asymptotic regime
1<<\omega<<1/T_{BH}.Comment: 4 page
La renovación de la palabra en el bicentenario de la Argentina : los colores de la mirada lingüística
El libro reúne trabajos en los que se exponen resultados de investigaciones presentadas por investigadores de Argentina, Chile, Brasil, España, Italia y Alemania en el XII Congreso de la Sociedad Argentina de Lingüística (SAL), Bicentenario: la renovación de la palabra, realizado en Mendoza, Argentina, entre el 6 y el 9 de abril de 2010. Las temáticas abordadas en los 167 capítulos muestran las grandes líneas de investigación que se desarrollan fundamentalmente en nuestro país, pero también en los otros países mencionados arriba, y señalan además las áreas que recién se inician, con poca tradición en nuestro país y que deberían fomentarse. Los trabajos aquí publicados se enmarcan dentro de las siguientes disciplinas y/o campos de investigación: Fonología, Sintaxis, Semántica y Pragmática, Lingüística Cognitiva, Análisis del Discurso, Psicolingüística, Adquisición de la Lengua, Sociolingüística y Dialectología, Didáctica de la lengua, Lingüística Aplicada, Lingüística Computacional, Historia de la Lengua y la Lingüística, Lenguas Aborígenes, Filosofía del Lenguaje, Lexicología y Terminología
Autodeterminazione e responsabilità sanitaria: le trasfusioni di sangue nei pazienti Testimoni di Geova.
Il presente articolo inizia con una breve analisi delle ragioni bibliche perché i Testimoni di Geova rifiutano le trasfusioni, per analizzare il diritto all'autodeterminazione di un paziente, che si esercita attraverso il trattamento medico espresso al consenso informato. L'articolo esamina poi tre situazioni che un medico che sta trattando un Testimone di Geova può affrontare: una situazione clinica non urgente che consente diverse scelte di trattamento; una condizione che richiede scelte di trattamento obbligate ma differibili nel corso del tempo; infine, una situazione che costringe il medico a una singola scelta terapeutica non rinviata e prevedibile.The present article begins with a brief analysis of the biblical reasons why Jehovah's Witnesses refuse transfusions, to analyze the right to self-determination of a patient, which is exercised through the express informed consent to medical treatment. Then, the article examines three situations that a doctor who is treating a Jehovah's Witness may face: a non-urgent clinical situation that allows different treatment choices; a condition that requires treatment choices obliged but deferrable over time; and, finally, a situation that forces the doctor to a single therapeutic choice not postponed and predictable