RDM-stars and galactic rotation curves

The recently formulated model of black holes coupled to the radial flows of dark matter (RDM-stars) is considered and the shape of the galactic rotation curves predicted by the model is evaluated. Under the assumption that the density of black holes is proportional to the density of luminous matter, the model perfectly fits the experimental data, both for the universal rotation curve, describing the spiral galaxies of a general form, and for the grand rotation curve, describing the orbital velocities of Milky Way galaxy in a wide range of distances. The modeling of the galactic gravitational field at large distances from the center and out of the galactic plane is also discussed

Quantization of Non-Critical Bosonic Open String Theory

The theory of relativistic strings is considered in frames of Hamiltonian formalism and Dirac's quantization procedure. A special gauge fixing condition is formulated, related with the world sheet of the string in Lorentz-invariant way. As a result, a new set of Lorentz-invariant canonical variables is constructed, in which a consistent quantization of bosonic open string theory could be done in Minkowski space-time of dimension $d=4$. The obtained quantum theory possesses spin-mass spectrum with Regge-like behavior

Stability of white holes revisited

It is shown that the models of white hole interacting with external matter can be made stable by introduction of a negative central mass. Similar results are obtained for the models of white hole, interacting with null shells, with radial flows of matter and with photon gas. In realistic models, a naked timelike singularity corresponding to the negative mass is hidden under a coat of positive mass, providing an extremely strong redshift for photons born in the Planck neighborhood of the singularity and observed at infinity, thereby realizing the principle of cosmic censorship in a relaxed form

Wormhole solutions of RDM model

The model of a spiral galaxy with radially directed flows of dark matter is extended by exotic matter, in a form of a perfect fluid with a linear anisotropic equation of state. The exotic matter is collected in the minimum of gravitational potential and opens a wormhole in the center of the galaxy. The flows of dark matter pass through the wormhole and form a mirror galaxy on the other side. The influence of model parameters to the shape of solution is studied, a solution matching parameters of Milky Way galaxy is computed

Tachyonic models of dark matter

We consider a spherically symmetric stationary problem in General Relativity, including a black hole, inflow of normal and tachyonic matter and outflow of tachyonic matter. Computations in a weak field limit show that the resulting concentration of matter around the black hole leads to gravitational effects equivalent to those associated with dark matter halo. In particular, the model reproduces asymptotically constant galactic rotation curves, if the tachyonic flows of the central supermassive black hole in the galaxy are considered as a main contribution

String theory in Lorentz-invariant time-like gauge

A theory of closed bosonic string in time-like gauge, related in Lorentz-invariant way with the world sheet, is considered. Absence of quantum anomalies in this theory is shown.Comment: 10 pages, 5 figure

RDM-stars as sources of fast radio bursts

In this work we consider a recently formulated model of a black hole coupled with radially directed flows of dark matter (RDM-star). In this model, a cutoff by quantum gravity (QG) creates a core of Planck density, filled with a gas of Planck mass particles, inside the star. Further, in this model, a fast radio burst (FRB) can be generated via the following mechanism. An object of an asteroid mass falls onto an RDM-star. Due to large gravitational forces available in the interior, the RDM-star works as a powerful accelerator, boosting the nucleons composing the object to extremely high energies. Upon collision with the core, the nucleons enter in deeply inelastic reactions with the Planck particles composing the core. This process is followed by stimulated emission of highly energetic photons. On the way outside, these photons are subjected to a strong redshift factor, downscaling their frequencies to the radio diapason, as a result producing an FRB. A straightforward computation gives a characteristic upper FRB frequency of 0.6GHz. With attenuation factors, it is stretched to a range 0.35-8GHz, fitting well with the observable FRB frequencies. We also discuss the reconstruction of other FRB parameters in frames of the model.Comment: added references (ref.12 and ref.42

Statistical analysis of narrow-band signals at setilive.org

SETILive is a web project forwarding radio signals from SETI Institute's Allen Telescope Array (ATA) for the analysis of volunteers. It contains a large archive with more than 1.5 millions observations for more than 7.5 thousands observation targets, including directions to exoplanets discovered by telescope Kepler and other sources. It also supports various tools for signal collection and classification. Till recent time it supported live feeds of signals from ATA together with a feedback loop, a possibility to interrupt the schedule and repeat the observation of an interesting signal registered by sufficiently many viewers. Unfortunately, since 12-Oct-2014 the live feeds have been discontinued. We hope that the project will persist, taking into account the importance of the search subject, the worldwide interest to the topic and the value of already collected data. In this paper we present the results of statistical analysis of data stored in SETILive archive, using Radon transform and specially constructed filter for selection of single beams, potential signals of ET origination. We will also estimate statistical significance of signals depending on their signal-to-noise ratio using Monte Carlo simulation and select 28 strong signals and totally 1072 statistically significant signals in the archive

String theory in Lorentz-invariant light cone gauge

Quantization of 4-dimensional Nambu-Goto theory of open string in light cone gauge, related in Lorentz-invariant way with the world sheet, is performed. Obtained quantum theory has no anomalies in Lorentz group. Determined spin-mass spectra of the theory have Regge-like behavior and do not contain the tachyon. Vertex operators of interaction theory, acting in the physical subspace, are constructed.Comment: 15 pages, 9 figures, 3 tables; talk at Int. School of Subnuclear Physics, Aug 29 - Sept 7 1998, Erice (Sicily); submitted to Int.J.Mod.Phys.

String theory in Lorentz-invariant light cone gauge - II

We perform a quantization of 4-dimensional Nambu-Goto theory of open string in light cone gauge, related in Lorentz-invariant way with the world sheet. This allows to obtain a quantum theory without anomalies in Lorentz group. We consider a special type of gauge fixing conditions, imposed in oscillator sector of the theory, which lead to a relatively simple Hamiltonian mechanics, convenient for canonical quantization. We discuss the algebraic and geometric properties of this mechanics and determine its mass spectrum for the states of spin singlet S=0.Comment: misprint in fig.7 of Appendix 2 is correcte