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O. A. Soloviev

Publications and source records attributed to O. A. Soloviev.

14 recordsLinked to original sources
arXiv2000

Towards a Field Theory of the Plateau Transition

We suggest a procedure for calculating correlation functions of the local densities of states (DOS) at the plateau transitions in the Integer Quantum Hall effect (IQHE). We argue that their correlation functions are appropriately described in terms of the SL($2,{\Bbb C}$)/SU(2) WZNW model (at the usual Ka{\v c}--Moody point and with the level $6 \leq k \leq 8$). In this model we have identified the operators corresponding to the local DOS, and derived the partial differential equation determining their correlation functions. The OPEs for powers of the local DOS obtained from this equation are in agreement with available results.

cond-mat↗
arXiv1998

Gravitationally dresed RG flows and zig-zag invariant strings

We propose a world-sheet realization of the zigzag-invariant bosonic and fermionic strings as a perturbed Wess-Zumino-Novikov-Witten model at large negative level $k$ on a group manifold $G$ coupled to 2D gravity. In the large $k$ limit the zigzag symmetry can be obtained as a result of a self-consistent solution of the gravitationally dressed RG equation. The only solution found for simple group is $G=SL(2)$. More general target-space geometries can be obtained via tensoring of various cosets based on SL(2). In the supersymmetric case the zigzag symmetry fixes the maximal target-space dimension of the confining fermionic string to be seven.

hep-th↗
arXiv1997

Knizhnik-Zamolodchikov-type equations for gauged WZNW models

We study correlation functions of coset constructions by utilizing the method of gauge dressing. As an example we apply this method to the minimal models and to the Witten 2D black hole. We exhibit a striking similarity between the latter and the gravitational dressing. In particular, we look for logarithmic operators in the 2D black hole.

hep-th↗
arXiv1996

Gauged Knizhnik-Zamolodchikov equation

Correlation functions of gauged WZNW models are shown to satisfy a differential equation, which is a gauge generalization of the Knizhnik-Zamolodchikov equation.

hep-th↗
arXiv1995

Conformal Points and Duality of Non-Abelian Thirring Models and Interacting WZNW Models

We show that the strong coupling phase of the non-Abelian Thirring model is dual to the weak-coupling phase of a system of two WZNW models coupled to each other through a current-current interaction. This latter system is integrable and is related to a perturbed conformal field theory which, in the large $|k|$ limit, has a nontrivial zero of the perturbation-parameter beta-function. The non-Abelian Thirring model reduces to a free fermion theory plus a topological field theory at this critical point, which should therefore be identified with the isoscalar Dashen-Frishman conformal point. The relationship with the Gross-Neveu model is discussed.

hep-th↗
arXiv1994

Perturbed Gauged WZNW Models

We discuss a new type of unitary perturbations around conformal theories inspired by the $σ$-model perturbation of the nonunitary WZNW model. We show that the nonunitary level $k$ WZNW model perturbed by its sigma model term goes to the unitary level $-k$ WZNW model. When plugged into the gauged WZNW model the given perturbation results in the perturbed gauged WZNW model which no longer describes a coset construction. We consider the BRST invariant generalization of the sigma model perturbation around the gauged WZNW model. In this way we obtain perturbed coset constructions. In the case of the $SU_{m-2}(2)\times SU_1(2)/SU_{m-1}(2)$ coset, the BRST invariant sigma model perturbation is identical to Zamolodchikov's $Φ_{(3,1)}$ perturbation of the minimal conformal series. The existence of general geometry flows is clarified.

hep-th↗
arXiv1994

Conformal Invariance of Interacting WZNW Models

We consider two level $k$ WZNW models coupled to each other through a generalized Thirring-like current-current interaction. It is shown that in the large $k$ limit, this interacting system can be presented as a two-parameter perturbation around a nonunitary WZNW model. The perturbation operators are the sigma model kinetic terms with metric related to the Thirring coupling constants. The renormalizability of the perturbed model leads to an algebraic equation for couplings. This equation coincides with the master Virasoro equation. We find that the beta functions of the two-parameter perturbation have nontrivial zeros depending on the Thirring coupling constants. Thus we exhibit that solutions to the master equation provide nontrivial conformal points to the system of two interacting WZNW models.

hep-th↗
arXiv1994

Solutions of the Master Virasoro Equations as Conformal Points of Perturbed WZNW Model

It is shown that the master equation of the affine-Virasoro construction on the unitary affine algebra naturally emerges in the fusion algebra of the nonunitary level $k$ WZNW model. Operators corresponding to solutions of the master equation are suitable for performing one-parametrical renormalizable perturbation around the given conformal nonunitary WZNW model. In the large $|k|$ limit, the infrared fixed point of the renormalization group beta function is found. There are as many infrared conformal points as $\frac{1}{2}N(N+1)$, where $N$ is the total number of solutions of the master equation.

hep-th↗
arXiv1994

Towards c=0 Flows

We discuss some implications of the gravitational dressing of the renormalization group for conformal field theories perturbed by relevant operators. The renormalization group flows are defined with respect to the dilatation operator associated with the $J_0^{(0)}$ mode of the $SL(2,R)$ affine algebra. We discuss the possibility of passing under the $c=25$ barrier along renormalization group flows in some models.

hep-th↗
arXiv1994

Superspace Supervortices

We present the theory describing supersymmetrical vortices in the curved superspace of the (1,0) supergravity. The action is defined as a (1,0) locally supersymmetric $SU(2)/U(1)$ coset perturbed by the cosmological constant-like term. The perturbation is such that it preserves the integrability of the coset model. Because of supersymmetry the perturbed theory is an exact quantum system provided a proper dilaton is taken into account. The exact value of the dilaton is determined in the supersymmetric case by the quasi-classical background of the bosonic coset.

hep-th↗
arXiv1994

The Gauged WZNW Model Perturbed by the Sigma Model Term

We discuss special perturbations of the gauged level $k$ WZNW model inspired by the $σ$-model perturbation of the nonunitary WZNW model. In the large $k$ limit there is a second conformal point in the vicinity of the ultarviolet fixed point. At the second critical point the conformal model has a rational Virasoro central charge which no longer corresponds to a coset construction. In spite of this fact the perturbative conformal model appears to be a unitary system as long as the underlying coset construction at the ultraviolet critical point is unitary.

hep-th↗
arXiv1993

Conformal non-Abelian Thirring models

The Lie-Poisson structure of non-Abelian Thirring models is discussed and the Hamiltonian quantization of these theories is carried out. The consistency of the Hamiltonian quantization with the path integral method is established. It is shown that the space of non-Abelian Thirring models contains the nonperturbative conformal points which are in one-to-one correspondence with general solutions of the Virasoro master equation. A BRST nature of the mastert equation is clarified.

hep-th↗
arXiv1993

A symplectic structure for the space of quantum field theories

We use the formal Lie algebraic structure in the ``space'' of hamiltonians provided by equal time commutators to define a Kirillov-Konstant symplectic structure in the coadjoint orbits of the associated formal group. The dual is defined via the natural pairing between operators and states in a Hilbert space.

hep-th↗