Modified-gravity wormholes without exotic matter
TEX-ed March 22, 2013)A fundamental ingredient in wormhole physics is the ﬂaring-out condition at the throat which,in classical general relativity, entails the violation of the null energy condition. In this work, wepresent the most general conditions in the context of modiﬁed gravity, in which the matter threadingthe wormhole throat satisﬁes all of the energy conditions, and it is the higher order curvatureterms, which may be interpreted as a gravitational ﬂuid, that support these nonstandard wormholegeometries. Thus, we explicitly show that wormhole geometries can be theoretically constructedwithout the presence of exotic matter, but are sustained in the context of modiﬁed gravity.