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K. Zarembo

Publications and source records attributed to K. Zarembo.

At least 73 records · Page 4Linked to original sources
arXiv1999

Structure of the Electric Flux in N=4 Supersymmetric Yang-Mills Theory

Correlators of Wilson loop operators with O_4=Tr(F_{μν}^2+...) are computed in N=4 super-Yang-Mills theory using the AdS/CFT correspondence. The results are compared with the leading order perturbative computations. As a consequence of conformal invariance, these correlators have identical forms in the weak and strong coupling limits for circular loops. They are essentially different for contours not protected by conformal symmetry.

hep-th↗
arXiv1999

Coleman-Weinberg Mechanism and Interaction of D3-Branes in Type 0 String Theory

The low-energy theory on the world volume of parallel static D3-branes of type 0 strings is the Yang-Mills theory with six scalar fields in the adjoint representation. One-loop corrections in this theory induce Coleman-Weinberg effective potential, which can be interpreted as an interaction energy of D3-branes. The potential is repulsive at short distances and attractive at large ones. In the equilibrium, a large number of D3-branes forms a spherical shell with the radius proportional to the characteristic energy scale of the world-volume theory.

hep-th↗
arXiv1999

Solitons on Branes

We examine the possibility that gauge field configurations on stacks of parallel Dp branes support topological solitons. We give an exhaustive list of possible soliton charges for p<7. We also discuss how configurations carrying the soliton charges can be constructed from intersecting branes.

hep-th↗
arXiv1999

Wilson Loop Correlator in the AdS/CFT Correspondence

The AdS/CFT correspondence predicts a phase transition in Wilson loop correlators in the strong coupling N=4, D=4 SYM theory which arises due to instability of the classical string stretched between the loops. We study this transition in detail by solving equations of motion for the string in the particular case of two circular Wilson loops. The transition is argued to be smoothened at finite `t Hooft coupling by fluctuations of the string world sheet and to be promoted to a sharp crossover. Some general comments about Wilson loop correlators in gauge theories are made.

hep-th↗
arXiv1999

Effective potential in non-supersymmetric SU(N) x SU(N) gauge theory and interactions of type 0 D3-branes

We study some aspects of short-distance interaction between parallel D3-branes in type 0 string theory as described by the corresponding world-volume gauge theory. We compute the one-loop effective potential in the non-supersymmetric SU(N) x SU(N) gauge theory (which is a Z_2 projection of the U(2N) n=4 SYM theory) representing dyonic branes composed of N electric and N magnetic D3-branes. The branes of the same type repel at short distances, but an electric and a magnetic brane attract, and the forces between self-dual branes cancel. The self-dual configuration (with the positions of the electric and the magnetic branes, i.e. the diagonal entries of the adjoint scalar fields, being the same) is stable against separation of one electric or one magnetic brane, but is unstable against certain modes of separation of several same-type branes. This instability should be suppressed in the large N limit, i.e. should be irrelevant for the large N CFT interpretation of the gauge theory suggested in hep-th/9901101.

hep-th↗
arXiv1998

Screening of Fractional Charges in (2+1)-dimensional QED

We show that the logarithmically rising static potential between opposite-charged sources in two dimensions is screened by dynamical fields even if the probe charges are fractional, in units of the charge of the dynamical fields. The effect is due to quantum mechanics: the wave functions of the screening charges are superpositions of two bumps localized both near the opposite- and the same-charge sources, so that each of them gets exactly screened.

hep-th↗
arXiv1998

Universality in Effective Strings

We demonstrate that, due to the finite thickness of domain walls, and the consequent ambiguity in defining their locations, the effective string description obtained by integrating out bulk degrees of freedom contains ambiguities in the coefficients of the various geometric terms. The only term with unambiguous coefficient is the zeroth order Nambu-Goto term. We argue that fermionic ghost fields which implement gauge-fixing act to balance these ambiguities. The renormalized string tension, obtained after integrating out both bulk and world-sheet degrees of freedom, can be defined in a scheme independent manner; and we compute the explicit finite expressions, to one-loop, for the case of compact quantum electrodynamics and phi-4 theory.

hep-ph↗
arXiv1998

Ground state in gluodynamics and $q\bar{q}$ potential

Static color charges in Yang-Mills theory are considered in the Schrödinger picture. Stationary states containing color sources, interquark potential and confinement criterion are discussed within the framework based on integration over gauge transformations which projects the vacuum wave functional on the space of physical, gauge-invariant states.

hep-th↗
arXiv1998

Interquark Potential in Schrodinger Representation

Static charges are introduced in Yang-Mills theory via coupling to heavy fermions. The states containing static color charges are constructed using integration over gauge transformations. A functional representation for interquark potential is obtained. This representation provides a simple criterion for confinement.

hep-th↗
arXiv1998

Renormalization of Functional Schroedinger Equation by Background Field Method

Renormalization group transformations for Schrödinger equation are performed in $ϕ^4$ and in Yang-Mills theories. The dependence of the ground state wave functional on rapidly oscillating fields is found. For Yang-Mills theory, this dependence restricts a possible form of variational ansatz compatible with asymptotic freedom.

hep-th↗
arXiv1997

Ground State in Gluodynamics and Quark Confinement

The properties of the ground state wavefunctional in gluodynamics responsible for confinement are considered. It is shown that confinement arises due to the generation of a mass gap in the averaging over the gauge group which is necessary to ensure the gauge invariance of the ground state. The string tension is calculated in assumption of a particular infrared behavior of the vacuum wavefunctional.

hep-th↗
arXiv1997

Phase Structure and Nonperturbative States in Three-Dimensional Adjoint Higgs Model

The thermodynamics of 3d adjoint Higgs model is considered. We study the properties of the Polyakov loop correlators and the critical behavior at the deconfinement phase transition. Our main tool is a reduction to the 2d sine-Gordon model. The Polyakov loops appear to be connected with the soliton operators in it. The known exact results in the sine-Gordon theory allow us to study in detail the temperature dependence of the string tension, as well as to get some information about a nonperturbative dynamics in the confinement phase. We also consider the symmetry restoration at high temperature which makes it possible to construct the phase diagram of the model completely.

hep-th↗
arXiv1997

Effective Action and Measure in Matrix Model of IIB Superstrings

We calculate an effective action and measure induced by the integration over the auxiliary field in the matrix model recently proposed to describe IIB superstrings. It is shown that the measure of integration over the auxiliary matrix is uniquely determined by locality and reparametrization invariance of the resulting effective action. The large--$N$ limit of the induced measure for string coordinates is discussed in detail. It is found to be ultralocal and, thus, possibly is irrelevant in the continuum limit. The model of the GKM type is considered in relation to the effective action problem.

hep-th↗
arXiv1997

Towards a Non-perturbative Formulation of IIB Superstrings by Matrix Models

We address the problem of a non-perturbative formulation of superstring theory by means of the recently proposed matrix models. For the model by Ishibashi, Kawai, Kitazawa and Tsuchiya (IKKT), we perform one-loop calculation of the interaction between operator-like solutions identified with D-brane configurations of type IIB superstring (in particular, for parallel moving and rotated static p-branes). Comparing to the superstring calculations, we show that the matrix model reproduces the superstring results only at large distances or small velocities, corresponding to keeping only the lowest mass closed string modes. We propose a modification of the IKKT matrix model introducing an integration over an additional Hermitian matrix required to have positive definite eigenvalues, which is similar to the square root of the metric in the continuum Schild formulation of IIB superstrings. We show that for this new matrix action the Nambu-Goto version of the Green-Schwarz action is reproduced even at quantum level.

hep-th↗
arXiv1997

Properties of D-Branes in Matrix Model of IIB Superstring

We discuss properties of D-brane configurations in the matrix model of type IIB superstring recently proposed by Ishibashi, Kawai, Kitazawa and Tsuchiya. We calculate central charges in supersymmetry algebra at infinite N and associate them with one- and five-branes present in IIB superstring theory. We consider classical solutions associated with static three- and five-branes and calculate their interactions at one loop in the matrix model. We discuss some aspects of the matrix-model formulation of IIB superstring.

hep-th↗
arXiv1996

Adjoint non-Abelian Coulomb gas at large N

The non-Abelian analog of the classical Coulomb gas is discussed. The statistical mechanics of arrays of classical particles which transform under various representations of a non-Abelian gauge group and which interact through non-Abelian electric fields are considered. The problem is formulated on the lattice and, for the case of adjoint charges, it is solved in the large N limit. The explicit solution exhibits a first order confinement-de-confinement phase transition with computable properties. In one dimension, the solution has a continuum limit which describes 1+1-dimensional quantum chromodynamics (QCD) with heavy adjoint matter.

hep-th↗
arXiv1996

Supersymmetric matrix models and branched polymers

We solve a supersymmetric matrix model with a general potential. While matrix models usually describe surfaces, supersymmetry enforces a cancellation of bosonic and fermionic loops and only diagrams corresponding to so-called branched polymers survive. The eigenvalue distribution of the random matrices near the critical point is of a new kind.

cond-mat↗