DOI 10.1007/s100529900229
Prescriptionless light-cone integrals
Instituto de
Física Teórica, Universidade Estadual Paulista, R.Pamplona,
145 São
Paulo - SP CEP 01405-900 Brazil
Received: 2 August 1999 / Published online: 8 December 1999
Abstract
Perturbative quantum gauge field theory as seen within the perspective
of physical
gauge choices such as the light-cone gauge entails the emergence of
troublesome poles
of the type
in the Feynman
integrals. These come from the boson field propagator, where
and 
is the external arbitrary four-vector
that defines
the gauge proper. This becomes an additional hurdle
in the
computation of Feynman diagrams, since any graph containing internal
boson
lines will inevitably produce integrands with denominators bearing
the
characteristic gauge-fixing factor. How one deals with them has
been the
subject of research over decades, and several prescriptions
have been
suggested and tried in the course of time, with failures and
successes.
However, a more recent development at this fronteer which applies
the negative
dimensional technique to compute light-cone Feynman integrals
shows that we can
altogether dispense with prescriptions to perform the calculations.
An
additional bonus comes to us attached to this new technique, in that
not only it
renders the light-cone prescriptionless but, by the very nature
of it, it can also
dispense with decomposition formulas or partial fractioning tricks
used in the
standard approach to separate pole products of the type
![$(k\cdot
n)^{-\alpha}[(k-p)\cdot n]^{-\beta}$](/articles/epjc/abs/2000/02/epjc0229/img4.gif){kind=small}
(
).
In this work we demonstrate how all this can be done.
Copyright Springer-Verlag 2000
