Albert Petrov - Academia.edu (original) (raw)

Papers by Albert Petrov

Research paper thumbnail of Vector-Tensor Gravities and Problem of Lorentz Symmetry Breaking in Gravity

SpringerBriefs in Physics

In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity an... more In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity and bumblebee gravity, for which we discuss some exact solutions. The special attention is devoted to the problem of spontaneous breaking of Lorentz symmetry in a curved space-time which motivated these models. Besides, we present a general discussion of possibility of developing a consistent Lorentz-breaking extension for gravity.

Research paper thumbnail of Lorentz Symmetry Breaking—Classical and Quantum Aspects

SpringerBriefs in Physics

In this book, we review various aspects of the Lorentz symmetry breaking, both classical and quan... more In this book, we review various aspects of the Lorentz symmetry breaking, both classical and quantum ones, with the special interest to perturbative generation of Lorentz-breaking terms. We present impacts of Lorentz symmetry breaking in noncommutative and supersymmetric theories. Also, we discuss the problem of Lorentz symmetry breaking in a curved space-time. The book is closed with a review of experimental studies of Lorentz symmetry breaking.

Research paper thumbnail of Nonlocal Gravity

SpringerBriefs in Physics, 2020

Research paper thumbnail of Scalar-Tensor Gravities

SpringerBriefs in Physics, 2020

In this chapter, we discuss scalar-tensor gravities where the extra scalar field, treated as an i... more In this chapter, we discuss scalar-tensor gravities where the extra scalar field, treated as an ingredient of a complete description of gravity itself rather than the matter field, is introduced. The main attention is devoted to the Chern-Simons modified gravity allowing for breaking of CPT, and in certain situations, also of Lorentz symmetry, for which we discuss both classical solutions and some quantum aspects, namely perturbative generation. Besides of the Chern-Simons modified gravity, we discuss some classical solutions in Brans-Dicke gravity and give a brief introduction to galileons theory.

Research paper thumbnail of Supersymmetry Breaking

Fundamental Theories of Physics, 2021

Research paper thumbnail of Four-Dimensional Superfield Supersymmetry

Quantum Superfield Supersymmetry, 2021

Research paper thumbnail of Einstein Gravity and the Need for Its Modification

In this chapter we present a brief introduction to the general relativity, describe most importan... more In this chapter we present a brief introduction to the general relativity, describe most important classical solutions of the Einstein equations, and formulate the main problems which cannot be solved within Einstein gravity, that is, the problems of renormalizability and of cosmic acceleration.

Research paper thumbnail of Horava–Lifshitz Gravity

In this chapter we discuss the Horava-Lifshitz gravity whose key property consists in a strong ti... more In this chapter we discuss the Horava-Lifshitz gravity whose key property consists in a strong time-space asymmetry allowing to introduce higher spatial derivatives in order to improve renormalizability of the theory, and maintain only second time derivatives avoiding ghosts. For this theory, we write down equations of motion and present most important classical solutions, namely, cosmological metric, black hole and Godel-type metric. Besides of this, we review some extensions of Horava-Lifshitz gravity.

Research paper thumbnail of Effective Action and Loop Expansion: General Formulation

Research paper thumbnail of Vector-Tensor Gravities and Problem of Lorentz Symmetry Breaking in Gravity

In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity an... more In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity and bumblebee gravity, for which we discuss some exact solutions. The special attention is devoted to the problem of spontaneous breaking of Lorentz symmetry in a curved space-time which motivated these models. Besides, we present a general discussion of possibility of developing a consistent Lorentz-breaking extension for gravity.

Research paper thumbnail of Noncommutative quantization of the Maxwell-Chern-Simons theory

Research paper thumbnail of Superfield effective potential in the two-loop approximation

Research paper thumbnail of f (R)-brane

Research paper thumbnail of Superfield effective action within the general chiral superfield model

Physics of Atomic Nuclei, 2000

ABSTRACT

Research paper thumbnail of Superfield chiral effective potential

Physics Letters B, 1994

A superfield approach to compute the chiral effective superpotential in the Wess-Zumino model is ... more A superfield approach to compute the chiral effective superpotential in the Wess-Zumino model is developed. An explicit calculation of the potential in the two-loop approximation is described.

Research paper thumbnail of Modifications of the Pure Gravitational Sector

SpringerBriefs in Physics, 2020

In this chapter we discuss the modifications of the Einstein gravity based on introducing of addi... more In this chapter we discuss the modifications of the Einstein gravity based on introducing of additional terms to the pure gravitational sector, with the most important examples of these terms are functions of the scalar curvature itself and of higher curvature invariants, such as, for example, Gauss-Bonnet term. For these theories we consider modified Einstein equations and find some their solutions. Within this section, we do not restrict ourselves by the four-dimensional space-time, therefore we, in particular, discuss in great details the Lovelock gravity and some solutions of its equations of motion.

Research paper thumbnail of Dynamical Chern-Simons modified gravity and Friedmann-Robertson-Walker metric

arXiv (Cornell University), May 11, 2010

We study the conditions for the consistency of the Friedmann-Robertson-Walker (FRW) metric with t... more We study the conditions for the consistency of the Friedmann-Robertson-Walker (FRW) metric with the dynamical Chern-Simons modified gravity. It turns out to be that in this situation the accelerated expansion of the Universe takes place, with the time dependence of the scale factor turns out to be similar to the case of presence of the Chaplygin gas. Also we found that this modification changes the total density of the Universe and therefore gives a nontrivial impact to a cosmological scenario.

Research paper thumbnail of On the higher-derivative Lorentz-breaking terms

Proceedings of 7th International Conference on Mathematical Methods in Physics — PoS(ICMP 2012), 2013

Research paper thumbnail of Induction of the higher-derivative Chern–Simons extension in QED3

International Journal of Modern Physics A, 2016

We perform the perturbative generation of the higher-derivative Chern–Simons contribution to the ... more We perform the perturbative generation of the higher-derivative Chern–Simons contribution to the effective action in the three-dimensional QED at zero and finite temperatures. In the latter case, we show that as the temperature goes to infinity this contribution vanishes. However, as expected, as the temperature goes to zero only the covariant part survives. The noncovariant part contributes only in intermediate temperatures where it presents a maximum.

Research paper thumbnail of Note on the Gauss-Bonnet braneworld scenario

Research paper thumbnail of Vector-Tensor Gravities and Problem of Lorentz Symmetry Breaking in Gravity

SpringerBriefs in Physics

In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity an... more In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity and bumblebee gravity, for which we discuss some exact solutions. The special attention is devoted to the problem of spontaneous breaking of Lorentz symmetry in a curved space-time which motivated these models. Besides, we present a general discussion of possibility of developing a consistent Lorentz-breaking extension for gravity.

Research paper thumbnail of Lorentz Symmetry Breaking—Classical and Quantum Aspects

SpringerBriefs in Physics

In this book, we review various aspects of the Lorentz symmetry breaking, both classical and quan... more In this book, we review various aspects of the Lorentz symmetry breaking, both classical and quantum ones, with the special interest to perturbative generation of Lorentz-breaking terms. We present impacts of Lorentz symmetry breaking in noncommutative and supersymmetric theories. Also, we discuss the problem of Lorentz symmetry breaking in a curved space-time. The book is closed with a review of experimental studies of Lorentz symmetry breaking.

Research paper thumbnail of Nonlocal Gravity

SpringerBriefs in Physics, 2020

Research paper thumbnail of Scalar-Tensor Gravities

SpringerBriefs in Physics, 2020

In this chapter, we discuss scalar-tensor gravities where the extra scalar field, treated as an i... more In this chapter, we discuss scalar-tensor gravities where the extra scalar field, treated as an ingredient of a complete description of gravity itself rather than the matter field, is introduced. The main attention is devoted to the Chern-Simons modified gravity allowing for breaking of CPT, and in certain situations, also of Lorentz symmetry, for which we discuss both classical solutions and some quantum aspects, namely perturbative generation. Besides of the Chern-Simons modified gravity, we discuss some classical solutions in Brans-Dicke gravity and give a brief introduction to galileons theory.

Research paper thumbnail of Supersymmetry Breaking

Fundamental Theories of Physics, 2021

Research paper thumbnail of Four-Dimensional Superfield Supersymmetry

Quantum Superfield Supersymmetry, 2021

Research paper thumbnail of Einstein Gravity and the Need for Its Modification

In this chapter we present a brief introduction to the general relativity, describe most importan... more In this chapter we present a brief introduction to the general relativity, describe most important classical solutions of the Einstein equations, and formulate the main problems which cannot be solved within Einstein gravity, that is, the problems of renormalizability and of cosmic acceleration.

Research paper thumbnail of Horava–Lifshitz Gravity

In this chapter we discuss the Horava-Lifshitz gravity whose key property consists in a strong ti... more In this chapter we discuss the Horava-Lifshitz gravity whose key property consists in a strong time-space asymmetry allowing to introduce higher spatial derivatives in order to improve renormalizability of the theory, and maintain only second time derivatives avoiding ghosts. For this theory, we write down equations of motion and present most important classical solutions, namely, cosmological metric, black hole and Godel-type metric. Besides of this, we review some extensions of Horava-Lifshitz gravity.

Research paper thumbnail of Effective Action and Loop Expansion: General Formulation

Research paper thumbnail of Vector-Tensor Gravities and Problem of Lorentz Symmetry Breaking in Gravity

In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity an... more In this chapter we discuss the vector-tensor gravity theories, namely, Einstein-aether gravity and bumblebee gravity, for which we discuss some exact solutions. The special attention is devoted to the problem of spontaneous breaking of Lorentz symmetry in a curved space-time which motivated these models. Besides, we present a general discussion of possibility of developing a consistent Lorentz-breaking extension for gravity.

Research paper thumbnail of Noncommutative quantization of the Maxwell-Chern-Simons theory

Research paper thumbnail of Superfield effective potential in the two-loop approximation

Research paper thumbnail of f (R)-brane

Research paper thumbnail of Superfield effective action within the general chiral superfield model

Physics of Atomic Nuclei, 2000

ABSTRACT

Research paper thumbnail of Superfield chiral effective potential

Physics Letters B, 1994

A superfield approach to compute the chiral effective superpotential in the Wess-Zumino model is ... more A superfield approach to compute the chiral effective superpotential in the Wess-Zumino model is developed. An explicit calculation of the potential in the two-loop approximation is described.

Research paper thumbnail of Modifications of the Pure Gravitational Sector

SpringerBriefs in Physics, 2020

In this chapter we discuss the modifications of the Einstein gravity based on introducing of addi... more In this chapter we discuss the modifications of the Einstein gravity based on introducing of additional terms to the pure gravitational sector, with the most important examples of these terms are functions of the scalar curvature itself and of higher curvature invariants, such as, for example, Gauss-Bonnet term. For these theories we consider modified Einstein equations and find some their solutions. Within this section, we do not restrict ourselves by the four-dimensional space-time, therefore we, in particular, discuss in great details the Lovelock gravity and some solutions of its equations of motion.

Research paper thumbnail of Dynamical Chern-Simons modified gravity and Friedmann-Robertson-Walker metric

arXiv (Cornell University), May 11, 2010

We study the conditions for the consistency of the Friedmann-Robertson-Walker (FRW) metric with t... more We study the conditions for the consistency of the Friedmann-Robertson-Walker (FRW) metric with the dynamical Chern-Simons modified gravity. It turns out to be that in this situation the accelerated expansion of the Universe takes place, with the time dependence of the scale factor turns out to be similar to the case of presence of the Chaplygin gas. Also we found that this modification changes the total density of the Universe and therefore gives a nontrivial impact to a cosmological scenario.

Research paper thumbnail of On the higher-derivative Lorentz-breaking terms

Proceedings of 7th International Conference on Mathematical Methods in Physics — PoS(ICMP 2012), 2013

Research paper thumbnail of Induction of the higher-derivative Chern–Simons extension in QED3

International Journal of Modern Physics A, 2016

We perform the perturbative generation of the higher-derivative Chern–Simons contribution to the ... more We perform the perturbative generation of the higher-derivative Chern–Simons contribution to the effective action in the three-dimensional QED at zero and finite temperatures. In the latter case, we show that as the temperature goes to infinity this contribution vanishes. However, as expected, as the temperature goes to zero only the covariant part survives. The noncovariant part contributes only in intermediate temperatures where it presents a maximum.

Research paper thumbnail of Note on the Gauss-Bonnet braneworld scenario