Noncommutative-geometry wormholes without exotic matter

Noncommutative geometry inspired wormholes and dirty black holes

We provide new exact solutions of the Einstein equations which generalize the noncommutative geometry inspired Schwarzschild metric, previously obtained by the authors. We consider here more general equations of state and find new geometries describing both a regular “dirty black hole” and a “wormhole”. We discuss strong and weak energy condition violation and variuos aspects of the regular dir...

Singlet scalar dark matter in noncommutative space

In this paper, we examine the singlet scalar dark matter annihilation to becoming the Standard Model particles in the non-commutative space. In the recent decades, many candidates of dark matter have been offered,  but our information about  the nature of dark matter is still limited. There are such particle candidates as  scalar matetr, fermion, boson, gauge boson, etc.; however, they have nei...

Problems with Wormholes Which Involve Arbitrarily Small Amounts of Exotic Matter

A quantum inequality bound on the expectation value of the null-contracted stress tensor in an arbitrary Hadamard state is used to obtain constraints on the geometries of traversable wormholes. Particular attention is given to the wormhole models of Visser, Kar, and Dadhich (VKD) and to those of Kuhfittig. These are models which use arbitrarily small amounts of exotic matter for wormhole mainte...

Noncommutative geometry

Quantum mechanics without spacetime 1 - A case for noncommutative geometry -

Quantum mechanics in its presently known formulation requires an external classical time for its description. A classical spacetime manifold and a classical spacetime metric are produced by classical matter fields. In the absence of such classical matter fields, quantum mechanics should be formulated without reference to a classical time. If such a new formulation exists, it follows as a conseq...