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Sergio L. Cacciatori Marco M. Caldarelli Alex Giacomini Dietmar Klemm Diego S. Mansi 《Journal of Geometry and Physics》2006,56(12):2523-2543
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 , and , 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 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 Chern–Simons theory. 相似文献
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