Papers by George Lavrelashvili
Nonconservation of fermion quantum numbers in the case of tunneling transitions in gauge theories
Theor Math Phys Engl Tr, 1987
ABSTRACT
This is a brief review of the main properties of sphalerons in various theories with a Yang--Mill... more This is a brief review of the main properties of sphalerons in various theories with a Yang--Mills field. Talk given at the Heat Kernel Techniques and Quantum Gravity, Winnipeg, Canada, August 2-6, 1994.
Nuclear Physics B, Dec 1, 1993
We present numerical and analytical results on static spherically symmetric solutions of an SU(2)... more We present numerical and analytical results on static spherically symmetric solutions of an SU(2) Yang-Mills field coupled to the gravitational field and to a dilaton. For any value of the dilaton coupling constant we find a discrete family of globally regular solutions of finite mass. In addition our analysis indicates the existence of a similar discrete family of black hole solutions for any given radius rh of their horizon. All these solutions turn out to be unstable in linearized perturbation theory.
We discuss properties of globally regular and black hole solutions of the Einstein-Yang-Mills-dil... more We discuss properties of globally regular and black hole solutions of the Einstein-Yang-Mills-dilaton theory.
Mod Phys Lett a, 1994
We discuss the properties and interpretation of a discrete sequence of a static spherically symme... more We discuss the properties and interpretation of a discrete sequence of a static spherically symmetric solutions of the Yang-Mills dilaton theory. This sequence is parametrized by the number of zeros, n, of a component of the gauge field potential. It is demonstrated that solutions with odd n possess all the properties of the sphaleron. It is shown that there are normalizable fermion zero modes in the background of these solutions. The question of instability is critically analyzed.
Breakdown in quantum coherence under changes of spatial topology in quantum gravity
ABSTRACT
Static Spherically Symmetric Solutions of Scalar Gravity with SU(2) Gauge Field
We discuss properties and interpretation of recently found globally regular and black hole soluti... more We discuss properties and interpretation of recently found globally regular and black hole solutions of a Einstein-Yang-Mills-dilaton theory.
Creation of semi-closed worlds during the false vacuum decay
Physics of Atomic Nuclei
We present a brief review of some recent results on non-abelian solitons and black holes in diffe... more We present a brief review of some recent results on non-abelian solitons and black holes in different theories. Lecture given at the Simi-96, Tbilisi, Georgia, September 22-28, 1996.
On wormholes in low energy string theory
Helvetica Physica Acta
Instability of 6 dimensional Rubakov-Shaposhnikov model is reinvestigated. It is shown that the m... more Instability of 6 dimensional Rubakov-Shaposhnikov model is reinvestigated. It is shown that the model is unstable in scalar perturbations sector with very particular instability pattern: there are no unstable modes for the first two lowest angular harmonics, m=0 and m=1, whereas there is a single negative mode for each higher m. Comment: 7 pages, including 1 figure
Static spherically symmetric solutions of a Yang-Mills field coupled to a dilaton
Physics Letters B, 1992
We have performed a detailed numerical and analytical study of static spherically symmetric solut... more We have performed a detailed numerical and analytical study of static spherically symmetric solutions of an SU (2) Yang-Mills field coupled to a scalar graviton (dilaton). The results show a striking similarity to those obtained for the Einstein-Yang-Mills theory by Bartnik and ...
The cosmological constant, third quantization and all that
Lecture Notes in Physics, 1991
ABSTRACT The paper consists of two main parts. The first part contains a short review of recent w... more ABSTRACT The paper consists of two main parts. The first part contains a short review of recent works on the application of the third quantization method to the cosmological constant problem. In the second part critical consideration is given to Dirac's scheme of gravity quantization. We suppose that Dirac's scheme may turn out inadequate for gravity quantization because of anomalies arising in the algebra of constraints.
Physics Letters B, 1992
We discuss the properties of a new type of classical solution in theories with vacuum periodicity... more We discuss the properties of a new type of classical solution in theories with vacuum periodicity. This type of solution is in real time and satisfies special boundary conditions. The analytic expression of such a solution in the simplest (0 + 1 )-dimensional model is found.
Nuclear Physics B - Proceedings Supplements, 2000
There is a single negative mode in the spectrum of small perturbations about the tunneling soluti... more There is a single negative mode in the spectrum of small perturbations about the tunneling solutions describing a metastable vacuum decay in flat spacetime. This mode is needed for consistent description of decay processes. When gravity is included the situation is more complicated. There are different answers in different reduction schemes. An approach based on elimination of scalar field perturbations shows no negative mode, whereas the recent approach based on elimination of gravitational perturbations indicates presence of a negative mode. In this contribution we analyse and compare the present approaches to the negative mode problem in false vacuum decay with gravity.
Talk given at the 7th Marcel Grossmann Meeting on General Relativity, Stanford University, July 2... more Talk given at the 7th Marcel Grossmann Meeting on General Relativity, Stanford University, July 24-30, 1994.
A Negative Mode about the Hawking-Turok Instanton
Nonconservation of fermion quantum numbers in the case of tunneling transitions in gauge theories
Theoretical and Mathematical Physics, 1987
ABSTRACT
Physical Review D, 2004
We evaluate the one-loop prefactor in the false vacuum decay rate in a theory of a self interacti... more We evaluate the one-loop prefactor in the false vacuum decay rate in a theory of a self interacting scalar field in 3 + 1 dimensions. We use a numerical method, established some time ago, which is based on a well-known theorem on functional determinants. The proper handling of zero modes and of renormalization is discussed. The numerical results in particular show that quantum corrections become smaller away from the thin-wall case. In the thin-wall limit the numerical results are found to join into those obtained by a gradient expansion. 1
Uploads
Papers by George Lavrelashvili