Cosmic Jets in General Relativity

TL;DR

This paper reviews the formation of cosmic jets in general relativity, demonstrating how gravitational fields can produce particles and waves that align at near-light speeds, and explores scalar field propagation related to jet formation.

Contribution

It introduces and analyzes two theoretical scenarios for gravitationally induced cosmic jets and examines scalar field propagation to understand jet formation mechanisms.

Findings

Cosmic jets can form in time-dependent gravitational fields.

Scalar wave perturbations relate to particle motion in jets.

Theoretical models demonstrate jet formation processes.

Abstract

In certain general relativistic time-dependent gravitational fields, free test particles can asymptotically line up relative to fiducial static observers and produce a cosmic jet whose speed approaches the speed of light. Two scenarios for the formation of these purely gravitational jets have thus far been theoretically demonstrated: the double-jet collapse scenario and the wave scenario that involves both a cosmic jet in the general direction of wave propagation as well as a counterjet in the opposite direction. These scenarios are briefly reviewed in this paper. Moreover, to elucidate the process of jet formation in these scenarios, we study the propagation of scalar fields in related gravitational fields in connection with the correspondence between the scalar wave perturbations and the motion of free test particles and null rays.