We construct an exact solution describing the collision of two Kaluza-Klein “bubbles of nothing” in 3+1 dimensions. When the bubbles collide, a curvature singularity forms which is hidden inside an event horizon. However, unlike the formation of ordinary black holes, in this case the spacetime resembles the entire maximally extended Schwarzschild solution. We also point out that there are inequ...

Formulation of the problem. The regulatory and legal principles competence state authorities local self-government in Ukraine formation have been studied. contents key laws regarding bodies modern concepts their activities are disclosed. It was found that there is no unified conceptual vision status, competencies, responsibilities Ukraine. has established framework for functioning development f...

Topology optimization methods have widely been used in various industries, owing to their potential for providing promising design candidates mechanical devices. However, applications are usually limited the objects which do not move significantly due difficulty computationally efficient handling of contact and interactions among multiple structures or with boundaries by conventionally simulati...

In this paper we explore further the connections between convex bodies related to quantum correlation experiments with dichotomic variables and related bodies studied in combinatorial optimization, especially cut polyhedra. Such a relationship was established in Avis, Imai, Ito and Sasaki (2005 J. Phys. A: Math. Gen. 38 10971–87) with respect to Bell inequalities. We show that several well know...

We compute the probability distribution of the invariant separation between nucleation centers of colliding true vacuum bubbles arising from the decay of a false de Sitter space vacuum. We find that even in the limit of a very small nucleation rate (ΓH−5 ≪ 1) the production of widely separated bubble pairs is suppressed. This distribution is of particular relevance for the recently proposed “co...

Charge exchange collisions between highly charged Mg ions in colliding laserproduced magnesium plasmas are studied. Pinhole photography and XUV spectroscopy are used as diagnostic tools. XUV pinhole pictures taken at early stages give more insight into the expansion dynamics of the colliding magnesium plasmas. Spectroscopic studies show selective population of the n = 3 levels of Mg IX ions whi...