MG11 
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Quasinormal modes for arbitrary spins in the Schwarzschild background

The leading term of the asymptotic of quasinormal modes in the Schwarzschild background, $\omega_n = - i n/2$, is obtained in two straightforward analytical ways for arbitrary spins. One of these approaches requires almost no calculations. As simply we demonstrate that for any odd integer spin, described by the Teukolsky equation, the first correction to the leading term vanishes. Then, this correction for half-integer spins is obtained in a slightly more intricate way. At last, we derive analytically the general expression for the first correction for all spins, described by the Teukolsky equation.

Upper limits on density of dark matter in Solar system

The analysis of the observational data for the secular perihelion precession of Mercury, Earth, and Mars, based on the EPM2004 ephemerides, results in new upper limits on density of dark matter in the Solar system.

On the true value of Barbero-Immirzi parameter in loop quantum gravity

Various approaches to calculation of Barbero-Immirzi parameter in loop quantum gravity are discussed. Its true value is pointed out.

Radiation of Quantized Black Holes

Under quite natural general assumptions, the following results are obtained. The maximum entropy of a quantized surface is demonstrated to be proportional to the surface area in the classical limit. The general structure of the horizon spectrum is found. The discrete spectrum of thermal radiation of a black hole fits the Wien profile. The natural widths of the lines are much smaller than the distances between them.

IS RADIATION OF BLACK HOLES OBSERVABLE?

If primordial black holes (PBH) saturate the present upper limit on the dark matter density in our Solar system and if their radiation spectrum is discrete, the sensitivity of modern detectors is close to that necessary for detecting this radiation. On the other hand, if PBHs constitute an essential part of dark matter in our Galaxy, their radiation, either discrete or continuous, is well within the modern sensitivity, and can be possibly distinguished from the radiation of other sources. Even with present data, we arrive at the upper limit on the fraction of PBHs in the dark matter of our Galaxy on the level of $10^{-4}$. None of our conclusions are in conflict with the upper limits on the explosions accompanying final stages of the evolution of PBHs.