On the Global Embedding of Spacetime into Singular ES Einstein Manifolds: Wormholes

时空三喉虫洞

Spacetime triple wormhole

通过球面反演三环面构造了一个具有三个喉部的非薄壳、非球对称时空虫洞，并证明其为爱因斯坦场方程的非真空精确解，回答了爱因斯坦和罗森关于多喉解存在的问题。

Geometric structures of Morris-Thorne wormhole metric with the semi-symmetric non-metric connections

Spacetime is a 4-dimensional connected Lorentzian manifold. In this paper, we extend the Levi-Civita connection in the definition of spacetime to the semi-symmetric non-metric connection and conclude geometric structures admitted by the metric (1.1) with the semi-symmetric non-metric connections. Obviously, Morris-Thorne spacetime is Ricci generalized pseudosymmetry, Ricci generalized projectively pseudosymmetry, and has conformal 2-forms that are recurrent, etc. It also is an Einstein manifold of level 2 and 3-quasi-Einstein manifold.

Yamabe flow, conformal gravity and spacetime foam

It is shown that 3D part of a spherically symmetric solution in conformal Weyl gravity interacting with Maxwell electrodynamics is a Yamabe flow as well. The Yamabe flow describes the transition from a horn of an initial wormhole to a 3D Euclidean space both filled with a radial electric field. It is supposed that such transition may describe appearing/disappearing quantum wormholes in a spacetime foam.