DOI: 10.1140/epjc/s2003-01208
Some phenomenological consequences of the time-ordered perturbation theory of QED on non-commutative spacetime
Y. Liao and C. DehneInstitut für Theoretische Physik, Universität Leipzig, Augustusplatz 10/11, 04109 Leipzig, Germany liaoy@itp.uni-leipzig.de
dehne@itp.uni-leipzig.de
(Received: 29 November 2002 / Revised version: 11 March 2003 / Published online: 5 May 2003 )
Abstract
A framework was recently proposed for doing perturbation theory
on
non-commutative (NC) spacetime. It preserves the unitarity of
the
S matrix
and differs from the naive, popular approach already at the lowest
order in perturbation when time does not commute with space.
In this
work, we investigate its phenomenological implications at linear
colliders, especially the TESLA at DESY, through the processes
of
.
We find that some NC effects computed previously are now modified
and
that there are new processes which now exhibit NC effects.
Indeed, the first two processes get corrected at tree
level as opposed to the null result in the naive approach, while
the
third one coincides with the naive result only in the low energy
limit. The impact of the earth's rotation is incorporated. The
NC
signals are generally significant when the NC scale is comparable
to
the collider energy. If this is not the case, the non-trivial
azimuthal
angle distribution and day-night asymmetry of events due to
Lorentz
violation and the earth's rotation will be useful in identifying
signals.
We also comment briefly on the high energy behavior of the cross
section that grows linearly in the center of mass energy squared
and
argue that it does not necessarily contradict some statements,
e.g., the
Froissart-Martin bound, achieved in ordinary theory.
© Società Italiana di Fisica, Springer-Verlag 2003
