arXiv subjects

K. Demeterfi

Publications and source records attributed to K. Demeterfi.

4 recordsLinked to original sources

arXiv1995

Correlation Functions in Matrix Models Modified by Wormhole Terms

We calculate correlation functions in matrix models modified by trace-squared terms. First we study scaling operators in modified one-matrix models and find that their correlation functions satisfy modified Virasoro constraints. Then we turn to dressed order parameters in minimal models and show that their correlators satisfy Goulian-Li formulae continued to negative Liouville dressing exponents. Our calculations provide additional support for the idea that the modified matrix models contain operators with the negative branch of gravitational dressing.

hep-th↗

arXiv1993

The Exact $S$-matrix of the Deformed $c=1$ Matrix Model

We consider the $c=1$ matrix model deformed by the operator ${1\over 2} M\TrΦ^{-2}$, which was conjectured by Jevicki and Yoneya to describe a two-dimensional black hole of mass $M$. We calculate the exact non-perturbative $S$-matrix and show that all the amplitudes involving an odd number of particles vanish at least to all orders of perturbation theory. We conjecture that these amplitudes vanish non-perturbatively and prove this for the $2n \to 1$ scattering. For the 2-- and 4--particle amplitudes we give some leading terms of the perturbative expansion.

hep-th↗

arXiv1993

$1+1$-Dimensional Large $N$ QCD coupled to Adjoint Fermions

We consider 1+1-dimensional QCD coupled to Majorana fermions in the adjoint representation of the gauge group $SU(N)$. Pair creation of partons (fermion quanta) is not suppressed in the large-$N$ limit, where the glueball-like bound states become free. In this limit the spectrum is given by a linear \lc\ Schr\" odinger equation, which we study numerically using the discretized \lcq. We find a discrete spectrum of bound states, with the logarithm of the level density growing approximately linearly with the mass. The wave function of a typical excited state is a complicated mixture of components with different parton numbers. A few low-lying states, however, are surprisingly close to being eigenstates of the parton number, and their masses can be accurately calculated by truncated diagonalizations.

hep-th↗

arXiv1993

Light-cone approach to random surfaces embedded in two dimensions

We review the recently proposed \lc\ quantization of the matrix model which is expected to have a critical point describing 2-d quantum gravity coupled to $c=2$ matter. In the $N\to\infty$ limit, we derive a linear Schroedinger equation for the free string spectrum. Numerical study of this equation suggests that the spectrum is tachyonic, and that the string tension diverges at the critical point.

hep-th↗