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arXiv · 1502.02017

Wormholes with a barotropic equation of state admitting a one-parameter group of conformal motions

Peter K. F. Kuhfittig
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Abstract

The theoretical construction of a traversable wormhole proposed by Morris and Thorne maintains complete control over the geometry by assigning both the shape and redshift functions, thereby leaving open the determination of the stress-energy tensor. This paper examines the effect of introducing the linear barotropic equation of state $p_r=\omega\rho$ on the theoretical construction. If either the energy density or the closely related shape function is known, then the Einstein field equations do not ordinarily yield a finite redshift function. If, however, the wormhole admits a one-parameter group of conformal motions, then both the redshift and shape functions exist provided that $\omega <-1$. In a cosmological setting, the equation of state $p=\omega\rho$, $\omega <-1$, is associated with phantom dark energy, which is known to support traversable wormholes.

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Peter K. F. Kuhfittig. 2015-02-06. Wormholes with a barotropic equation of state admitting a one-parameter group of conformal motions. https://doi.org/10.1016/j.aop.2015.02.002

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