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Are Energy Conditions Violated by Expanding Wormholes?
N. Riazi et al.
Biruni Observatory, Shiraz University
Wormholes are topologically non-trivial structures which connect
two asymptotic universes. It is well known that static wormholes
violate energy conditions. We have obtained time-dependent so-
lutions of the Einstein and Brans-Dicke eld equations which rep-
resent evolving wormholes in a radiation-dominated cosmological
background. These solutions are classied into various groups and
studied separately. The time evolution of the GR solutions is the
same as that of the radiation-dominated FRW model. The space-
like hypersurfaces, however, dier as we get close to the wormhole.
It is shown that the energy conditions are not necessarily violated
in a nite time period and the supporting energy-momentum is
everywhere non-exotic. The problem is also studied in the frame-
work of the Brans-Dicke theory and conditions for the absence of
exotic matter are derived.
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