Spinning cylinders in general relativity: a canonical form for the Lewis metrics of the Weyl class

In the main article [CQG 38 (2021) 055003], a new "canonical" form for the Lewis metrics of the Weyl class has been obtained, depending only on three parameters -- Komar mass and angular momentum per unit length, plus the angle deficit -- corresponding to a coordinate system fixed to the "distant stars" and an everywhere timelike Killing vector field. Such form evinces the local but non-global static character of the spacetime, and striking parallelisms with the electromagnetic analogue. We discuss here its generality, main physical features and important limits (the Levi-Civita static cylinder, and spinning cosmic strings). We contrast it on geometric and physical grounds with the Kerr spacetime -- as an example of a metric which is locally non-static.
Comment: 15 pages, 2 figures. To appear in the Proceedings of the sixteenth Marcel Grossmann Meeting (MG16), July 5-10 2021; based on the invited talk "Gravitomagnetism in the Lewis cylindrical metrics", given in the parallel session PT5 -- "Dragging is never draggy: MAss and CHarge flows in GR"