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A recent paper (2012 emph{J. Phys. A} textbf{45} 374018) is extended by investigating the behavior of the regularized quantum scalar stress tensor near the axes of cones and their covering manifold, the Dowker space. A cone is parametrized by its angle $theta_1$, where $theta_1=2pi$ for flat space. We find that the tensor components have singularities of the type $r^gamma$, but the generic leading $gamma$ equals ${4pi over theta_1} - 2$, which is negative if and only if $theta_1>2pi$, and is a positive integer if $theta_1={2piover N}$. Thus the functions are analytic in those cases that can be solved by the method of images starting from flat space, and they are not divergent in the cases that interpolate between those. As a wedge of angle $alpha$ can be solved by images starting from a cone of angle $2alpha$, a divergent stress can arise in a wedge with $pi <alpha le 2pi$ but not in a smaller one.
Recent BICEP2 detection of low-multipole B-mode polarization anisotropy in the cosmic microwave background radiation supports the inflationary universe scenario and suggests a large inflaton field range. The latter feature can be achieved with axion
Vacuum energy is a simple model for dark energy driving an accelerated expansion of the universe. If the vacuum energy is inhomogeneous in spacetime then it must be interacting. We present the general equations for a spacetime-dependent vacuum energy
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Vacuum energy remains the simplest model of dark energy which could drive the accelerated expansion of the Universe without necessarily introducing any new degrees of freedom. Inhomogeneous vacuum energy is necessarily interacting in general relativi
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