Time and Tachyon
Abstract
Recent analysis suggests that the classical dynamics of a tachyon on an unstable Dbrane is described by a scalar Born-Infeld type action with a runaway potential. The
classical configurations in this theory at late time are in one to one correspondence with
the configuration of a system of non-interacting (incoherent), non-rotating dust. We
discuss some aspects of canonical quantization of this field theory coupled to gravity, and
explore, following earlier work on this subject, the possibility of using the scalar field
(tachyon) as the definition of time in quantum cosmology. At late ‘time’ we can identify
a subsector in which the scalar field decouples from gravity and we recover the usual
Wheeler - de Witt equation of quantum gravity.
CDS.CERN.CH
