Article

General class of wormhole geometries in conformal Weyl gravity

Classical and Quantum Gravity (Impact Factor: 3.1). 02/2008; 25(2008):175006. DOI: 10.1088/0264-9381/25/17/175006
Source: arXiv

ABSTRACT In this work, a general class of wormhole geometries in conformal Weyl gravity is analyzed. A wide variety of exact solutions of asymptotically flat spacetimes is found, in which the stress energy tensor profile differs radically from its general relativistic counterpart. In particular, a class of geometries is constructed that satisfies the energy conditions in the throat neighborhood, which is in clear contrast to the general relativistic solutions.

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Available from: Francisco S. N. Lobo, Nov 13, 2012
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    • "In fact, in the context of modified gravity it was shown that one may impose that the matter threading the wormhole satisfies the energy conditions, so that it is the effective stress-energy tensor containing higher order curvature derivatives that is responsible for the NEC violation. Thus, the higher order curvature terms, interpreted as a gravitational fluid, sustain these non-standard wormhole geometries, fundamentally different from their counterparts in general relativity [57] [58] [59] [60] [61] [62] [63] [64] [65]. "
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    • ", [56], [57], [58], [59], [60], [61], [62], [63], [64], [65], and [66]. "
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    • "In the context of nonlinear electrodynamics, it was found that certain dynamic wormhole solutions obey (suitably defined versions of) the WEC [18]. It is interesting to note that in modified theories of gravity, more specifically in f (R) gravity, the matter threading the wormhole throat can be forced to obey (suitably defined versions of) all the energy conditions, and it is the higher-order curvature terms that are responsible for supporting these wormhole geometries [19]. (Related issues arise when scalar fields are conformally coupled to gravity [20] [21].) "
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