Black Holes of a Minimal Size in String Gravity

A lower limit for a neutral black hole size is obtained in the frames of the string gravity model with the second order curvature correction. It is shown that this effect remains when the third order curvature correction is also taken into account and argued that such restriction does exist in all perturbative orders of curvature expansions.Comment: 6 LaTeX pages, 1 PostScript figure (epsfig.sty), minor changes in the text and references, submitted to Int.J.Mod.Phy

Political technologies and international conflicts in the information space of the Baltic Sea region

The information space of the Baltic region has gradually developed since the free exchange of cross-border messages was made possible by media technology and international law. The international conflict between Russia and some countries of the European Union has become a factor hampering its sustainable development. Moreover, the conflict has adversely affected the functioning of many civil society institutions in the Baltic Sea region. This study focuses on the publications in the scientific media associated with the political technologies that may provoke conflict but must contribute to good-neighbourly relations in the region. We carry out a comprehensive political analysis and a specific examination of the Western scientific media to develop a package of measures that Russia can take to counter the conflictprovoking influences in the region. The current condition of the regional information space and information operations aimed at inciting Russophobia and forcing Russia out of the European political process is indicative of the politicisation of social sciences and the humanities and of the mythologisation of the policies of the regional social structures. The conflict must be urgently resolved, since the political technologies, which cause instability in the information space, damage the reputations of all the states involved. To reconcile the differences that underlie the information conflict in the Baltic region it is necessary to take into account common interests. There is a pressing need to join efforts in solving the challenging social problems that cannot be overcome without either international cooperation among the countries or effective social partnership

Black Hole Shadows: How to Fix the Extended Gravity Theory

The first images of black hole shadows open new possibilities to develop modern extended gravity theories. We discuss the shadow calculations in non-rotating case both when $g_{11} = - g_{00}^{-1}$ and $g_{11} \neq - g_{00}^{-1}$. We demonstrate the application to few different models: Horndesky theory with Gauss-Bonnet invariant, loop quantum gravity and conformal gravity. The difference of these theories from shadow models with the theory of general relativity is shown. In addition we show that when the rotation is taken into account the requirements to the observational accuracy decrease