Deconstructing Frame Dragging

TL;DR

This paper investigates the origins of frame dragging in various spacetime scenarios, identifying universal physical quantities responsible for vorticity and providing a comprehensive understanding of the phenomenon beyond the classical rotating source explanation.

Contribution

It offers a unified analysis of vorticity and frame dragging across diverse spacetime models, revealing the fundamental physical quantities responsible for these effects.

Findings

Vorticity is linked to specific physical quantities present in all studied scenarios.

Frame dragging can occur without a rotating mass source, explained by identified physical factors.

The study provides a comprehensive physical picture of frame dragging phenomena.

Abstract

The vorticity of world lines of observers associated to the rotation of a massive body was reported by Lense and Thirring more than a century ago. In their example the frame dragging effect induced by the vorticity, is directly (explicitly) related to the rotation of the source. However in many other cases it is not so, and the origin of vorticity remains obscure and difficult to identify. Accordingly, in order to unravel this issue, and looking for the ultimate origin of vorticity associated to frame dragging, we analyze in this manuscript very different scenarios where frame dragging effect is present. Specifically we consider general vacuum stationary spacetimes, general electro-vacuum spacetimes, radiating electro-vacuum spacetimes and Bondi--Sachs radiating spacetimes. We identify the physical quantities present in all these cases, which determine the vorticity and may legitimately be considered as responsible for the frame dragging. Doing so we provide a comprehensive physical picture of frame dragging. Some observational consequences of our results are discussed.