کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1893790 | 1044110 | 2006 | 21 صفحه PDF | دانلود رایگان |
We consider various models of three-dimensional gravity with torsion or nonmetricity (metric affine gravity), and show that they can be written as Chern–Simons theories with suitable gauge groups. Using the groups ISO(2,1), SL(2,C) and SL(2,R)×SL(2,R), and the fact that they admit two independent coupling constants, we obtain the Mielke–Baekler model for zero, positive and negative effective cosmological constant respectively. Choosing SO(3,2) as the gauge group, one gets a generalization of conformal gravity that has zero torsion and only the trace part of the nonmetricity. This characterizes a Weyl structure. Finally, we present a new topological model of metric affine gravity in three dimensions arising from an SL(4,R) Chern–Simons theory.
Journal: Journal of Geometry and Physics - Volume 56, Issue 12, December 2006, Pages 2523–2543