Talk:Static spacetime

Suggestion for Future Work

Hi, MP,

Whoever eventually creates the article on hypersurface orthogonal should be sure to point to the proposed article on congruence of curves (oops! congruence is of course already taken by an article on a distinct concept in algebra), where someone should discuss the expansion and vorticity tensors, and the Frobenius theorem relating hypersurface orthogonal to vanishing vorticity. Also, citations should be sure to include the book by Eric Poisson, A Relativist's Toolkit, the exact solutions book, and Hawking & Ellis, Large Scale Structure of Spacetime, which all offer useful introductions to congruences, expansion, and vorticity. ---CH

Hi, CH.

Sounds like a good idea to mention the congruence of curves and all the other juicy concepts you mentioned. I may make a start on this soon - time permitting. ---MP

The article congruence (general relativity) gives a nice discussion of congruences, expansion, and vorticity (and shear) in general relativity. Thus, hypersurface orthogonal and vorticity tensor can be redirects to congruence (general relativity). I cannot create redirects, can someone do this? Then congruence of curves can be a rediect to congruence (manifolds). 67.198.37.16 (talk) 17:18, 21 February 2016 (UTC)

Non-static spacetime?

Is there a polar opposite to 'static spacetime'? That is, what is the sense of 'static'? Static as opposed to 'dynamic'? Static as opposed to 'active'? How is it meaningfully being applied? Are there solutions non-static spacetimes that are solutions to the Einstein Field Equations? Which ones are they? 70.247.167.104 (talk) 04:25, 4 February 2014 (UTC)

Static in the sense of "not changing over time". Examples of non-static spacetimes include the Kerr solution. Most ("almost all") solutions won't be static. e.g. anything with gravitational waves in them. 67.198.37.16 (talk) 17:28, 21 February 2016 (UTC)