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Conformal Anomaly of dual QFT from higher dimensional dilatonic gravity // Tomsk State Pedagogical University Bulletin. 2000. Issue 2 (18). P. 3-6

Using AdS/CFT correspondence we found the conformal anomaly from d3 and dS gauged supergravity with single scalar (dilaton) and the arbitrary scalar potential on AdS-like scalar-gravitational background. Such dilatonic gravity action describes the special RG flows in extended gauged SG when scalers lie in one-dimensional submanifold of complete scalars space. This dilaton-dependent conformal anomaly corresponds to dual non-conformal (gauge) QFT with account of radiative corrections and (or) masses. The attempt to define c-function away of conformity is presented.

Dark energy, inflation and dark mater from modified F(R) gravity // Tomsk State Pedagogical University Bulletin. 2011. Issue 8 (110). P. 7-19

We review modified F(R)-gravity as realistic candidate to describe the observable universe expansion history. We show that recent cosmic acceleration, radiation/matter-dominated epoch and inflation could be realized in the framework of F(R)-gravity in the unified way. For some viable classes of F(R)-gravity, the Newton law is respected and there is no so-called matter instability (the very heavy positive mass for additional scalar degree of freedom is generated). The reconstruction program in modified gravity is also reviewed and it is demonstrated that any time-evolution of the universe expansion could be realized in F(R)-gravity. These models remain to be realistic also in the presence of non-minimal gravitational coupling with usual matter. It is shown that same model which passes local tests and predicts the unification of inflation with cosmic acceleration also describes dark matter thanks to presence of additional scalar degree of freedom and chameleon mechanism.

Keywords: dark energy, cosmological singularity, cosmic acceleration

THE UNIVERSE EVOLUTION IN EXPONENTIAL F(R)-GRAVITY // Tomsk State Pedagogical University Bulletin. 2012. Issue 13 (128). P. 22-27

A generic feature of viable exponential F(R)-gravity is investigated. An additional modication to stabilize the effective dark energy oscillations during matter era is proposed and applied to two viable models. An analysis on the future evolution of the universe is performed. Furthermore, a unied model for early and late-time acceleration is proposed and studied.

Keywords: gravity, dark energy, universe, cosmology

EARLY-TIME COSMIC DYNAMICS IN F(R) AND F(|Ωˆ|) EXTENSIONS OF BORN-INFELD GRAVITY // Tomsk State Pedagogical University Bulletin. 2014. Issue 12 (153). P. 158-163

We consider two types of modifications of Born-Infeld gravity in the Palatini formulation and explore their dynamics in the early universe. One of these families considers f(R) corrections to the Born-Infeld Lagrangian, which can be seen as modifications of the dynamics produced by the quantum effects of matter, while the other consists on different powers of the elementary building block of the Born-Infeld Lagrangian, which we denote by |Ωˆ|. We find that the two types of nonsingular solutions that arise in the original Born-Infeld theory are also present in these extensions, being bouncing solutions a stable and robust branch. Singular solutions with a period of approximate de Sitter inflation are found even in universes dominated by radiation.

Keywords: Cosmology, nonsingular universes, modified gravity, Palatini formalism