عنوان مجله
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CANADIAN JOURNAL OF PHYSICS
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کلیدواژهها
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Lorentzian wormhole, de Sitter background, asymptotycally flat condition, volume integral quantifier, anti-de Sitter
background.
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چکیده
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There are a number of reasons to study wormholes with generic cosmological constant . Recent observations indicate
that the present accelerating expansion of the universe demands > 0. On the other hand, some extended theories of
gravitation, such as supergravity and superstring theories, possess vacuum states with < 0. Even within the framework of
general relativity, a negative cosmological 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
flat wormhole solutions in a generic cosmological constant background are studied. By constructing a specific class of
shape functions, a mass function, energy density, and pressure profile that 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 specific conditions. The possibility of setting different values for the parameters of the model helps us to find
exact solutions for the metric functions, mass functions, and energy–momentum profiles. At last, the volume integral quantifier,
which provides useful information about the total amount of energy-condition violating matter, is discussed briefly.
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