منابع مشابه
Once again on thin-shell wormholes in scalar-tensor gravity
It has been recently proved in a general form [1] that no wormholes can be formed in any scalartensor theory (STT) of gravity in which the non-minimal coupling function f(Φ) is everywhere positive and the scalar field Φ itself is not a ghost if matter sources of gravity respect the Null Energy Condition (NEC). In order to construct any viable and stable wormhole solution, attempts have been rec...
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Spherically symmetric thin-shell wormholes in the presence of a cosmological constant are constructed applying the cut-and-paste technique implemented by Visser. Using the Darmois-Israel formalism the surface stresses, which are concentrated at the wormhole throat, are determined. This construction allows one to apply a dynamical analysis to the throat, considering linearized radial perturbatio...
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Previous analysis about thin-shell wormholes associated to cosmic strings are extended. More evidence is found supporting the conjecture that, under reasonable assumptions about the equations of state of matter on the shell, the configurations are not stable under radial velocity perturbations.
متن کاملThe interplay of the collisionless non-linear thin-shell instability with the ion acoustic instability
The non-linear thin-shell instability (NTSI) may explain some of the turbulent hydrodynamic structures that are observed close to the collision boundary of energetic astrophysical outflows. It develops in non-planar shells that are bounded on either side by a hydrodynamic shock, provided that the amplitude of the seed oscillations is sufficiently large. The hydrodynamic NTSI has amicroscopic co...
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thin penetrable shell Nilima Nigam 1 Description of problem In this paper, we investigate the behaviour of solutions of a transmission problem in acoustics exterior to a thin domain, as the thickness of this domain approaches zero. The problem under consideration is : Find (u ; U ) 2 C2( ) \ C1( ) C2( 1) \ C1( 1) such that 8><>: 4 u + k2 0u = 0 in ; 4U + k2U = 0 on 1; u = 0 on ; u = U + f; @u @...
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ژورنال
عنوان ژورنال: Modern Physics Letters A
سال: 2017
ISSN: 0217-7323,1793-6632
DOI: 10.1142/s021773231750047x