There are a number of reasons to study wormholes with generic cosmological constant . Recent observations indicate that present accelerating expansion of the universe demands > 0. On the other hand, some extended theories of gravitation such as supergravity and superstring theories posses vacuum states with < 0. Even within the framework of general relativity, a negative cos- mological constant permits black holes with horizons topologically different from the usual spherical ones. These solutions are convertible to wormhole solutions by adding some exotic matter. In this paper, the asymptotically at wormhole solutions in a generic cosmological constant background are studied. By constructing a speci c class of shape functions, mass function, energy density and pressure pro les which support such a geometry are obtained. It is shown that for having such a geometry, the wormhole throat r0, the cosmological constant and the equation of state parameter ! should satisfy two speci c conditions. The possibility of setting different values for the parameters of the model helps us to nd exact solutions for the metric functions, mass functions and energy- momentum pro les. At last, the volume integral quanti er, which provides useful information about the total amount of energy condition violating matter is discussed brie y.
کلید واژگان :Wormhole
ارزش ریالی : 600000 ریال
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