1,314 research outputs found
Renormalization of the Fayet-Iliopoulos Term in Softly Broken SUSY Gauge Theories
It is shown that renormalization of the Fayet-Iliopoulos term in a softly
broken SUSY gauge theory, in full analogy with all the other soft terms
renormalizations, is completely defined in a rigid or an unbroken theory.
However, contrary to the other soft renormalizations, there is no simple
differential operator that acts on the renormalization functions of a rigid
theory and allows one to get the renormalization of the F-I term. One needs an
analysis of the superfield diagrams and some additional diagram calculations in
components. The method is illustrated by the four loop calculation of some part
of renormalization proportional to the soft scalar masses and the soft triple
couplings.Comment: Latex2e, 14 pages, uses axodraw.sty. References adde
Gauge and parametrization dependence in higher derivative quantum gravity
The structure of counterterms in higher derivative quantum gravity is
reexamined. Nontrivial dependence of charges on the gauge and parametrization
is established. Explicit calculations of two-loop contributions are carried out
with the help of the generalized renormgroup method demonstrating consistency
of the results obtained.Comment: 22 pages, Latex, no figure
Complex Curve of the Two Matrix Model and its Tau-function
We study the hermitean and normal two matrix models in planar approximation
for an arbitrary number of eigenvalue supports. Its planar graph interpretation
is given. The study reveals a general structure of the underlying analytic
complex curve, different from the hyperelliptic curve of the one matrix model.
The matrix model quantities are expressed through the periods of meromorphic
generating differential on this curve and the partition function of the
multiple support solution, as a function of filling numbers and coefficients of
the matrix potential, is shown to be the quasiclassical tau-function. The
relation to softly broken N=1 supersymmetric Yang-Mills theories is discussed.
A general class of solvable multimatrix models with tree-like interactions is
considered.Comment: 36 pages, 10 figures, TeX; final version appeared in special issue of
J.Phys. A on Random Matrix Theor
On the correspondence between the classical and quantum gravity
The relationship between the classical and quantum theories of gravity is
reexamined. The value of the gravitational potential defined with the help of
the two-particle scattering amplitudes is shown to be in disagreement with the
classical result of General Relativity given by the Schwarzschild solution. It
is shown also that the potential so defined fails to describe whatever
non-Newtonian interactions of macroscopic bodies. An alternative interpretation
of the -order part of the loop corrections is given directly in terms
of the effective action. Gauge independence of that part of the one-loop
radiative corrections to the gravitational form factors of the scalar particle
is proved, justifying the interpretation proposed.Comment: Latex 2.09, 3 ps. figures, 17 page
Boundary changing operators in the O(n) matrix model
We continue the study of boundary operators in the dense O(n) model on the
random lattice. The conformal dimension of boundary operators inserted between
two JS boundaries of different weight is derived from the matrix model
description. Our results are in agreement with the regular lattice findings. A
connection is made between the loop equations in the continuum limit and the
shift relations of boundary Liouville 3-points functions obtained from Boundary
Ground Ring approach.Comment: 31 pages, 4 figures, Introduction and Conclusion improve
Gauge dependence of effective gravitational field
The problem of gauge independent definition of effective gravitational field
is considered from the point of view of the process of measurement. Under
assumption that dynamics of the measuring apparatus can be described by the
ordinary classical action, effective Slavnov identities for the generating
functionals of Green functions corresponding to a system of arbitrary
gravitational field measured by means of scalar particles are obtained. With
the help of these identities, the total gauge dependence of the non-local part
of the one-loop effective apparatus action, describing the long-range quantum
corrections, is calculated. The value of effective gravitational field inferred
from the effective apparatus action is found to be gauge-dependent. A probable
explanation of this result, referring to a peculiarity of the gravitational
interaction, is given.Comment: Revised version as publishe
Infrared Quasi Fixed Points and Mass Predictions in the MSSM II: Large tan(beta) Scenario
We consider the infrared quasi fixed point solutions of the renormalization
group equations for the Yukawa couplings and soft supersymmetry breaking
parameters in the MSSM in the \underline{large } regime. The
existence of IR quasi fixed points together with the values of gauge couplings,
third generation quarks, lepton and Z-boson masses allows one to predict masses
of the Higgs bosons and SUSY particles as functions of the only free parameter,
, or the gluino mass. The lightest Higgs boson mass for TeV is found to be GeV for and
GeV for .Comment: 15 pages, LateX file with 4 eps figures, corrected numbers, new
column in table, last versio
Solution of gauge theories induced by fundamental representation scalars
Gauge theories induced by scalars in the fundamental representation of the
group are investigated in the large
and limit. A master field is defined from bilinears of the scalar
field following an Eguchi-Kawai type reduction of spacetime. The density
function for the master field satisfies an integral equation that can be solved
exactly in two dimensions (D=2) and in a convergent series of approximations at
. While at D=2 the system is in the same phase at all ,
it undergoes a phase transition at a critical value, , for
.Comment: 12 pages, LaTe
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