Wormhole geometries in fourth-order conformal Weyl gravity

Conformal Fourth-rank Gravity

We consider the consequences of describing the metric properties of space-time through a quartic line element ds = Gμνλρdx dxdxdx. The associated ”metric” is a fourth-rank tensor Gμνλρ. We construct a theory for the gravitational field based on the fourth-rank metric Gμνλρ which is conformally invariant in four dimensions. In the absence of matter the fourth-rank metric becomes of the form Gμνλ...

Topological Black Holes in Weyl Conformal Gravity

We present a class of exact solutions of Weyl conformal gravity, which have an interpretation as topological black holes. Solutions with negative, zero or positive scalar curvature at infinity are found, the former generalizing the wellknown topological black holes in anti-de Sitter gravity. The rather delicate question of thermodynamic properties of such objects in Weyl conformal gravity is di...

Wormhole geometries in modified teleparallel gravity and theenergy conditions

Higher Order Gravity , Gauge Invariant Variables , And Quantum Behavior In Weyl - Like Geometries

This paper presents the detailed, standard treatment of a simple, gauge invariant action for Weyl and Weyl-like Cartan geometries outlined in a previous paper. In addition to the familiar scalar curvature squared and Maxwell terms, the action chosen contains the logarithmic derivative of the scalar curvature combined with the intrinsic four vector (Weyl vector) in a gauge invariant fashion. Thi...

Conformal Continuations and Wormhole Instability in Scalar-tensor Gravity

We study the stability of static, spherically symmetric, traversable wormholes existing due to conformal continuations in a class of scalar-tensor theories with zero scalar field potential (so that Fisher’s well-known scalar-vacuum solution holds in the Einstein conformal frame). Specific examples of such wormholes are those with nonminimally (e.g., conformally) coupled scalar fields. All bound...