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arXiv · 1912.02987

On the Uniqueness of Einstein-Cartan Theory: Lagrangian, Covariant Derivative and Equation of Motion

Zi-Wei Chen·Run Diao·Xiang-Song Chen
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Abstract

In the standard Einstein-Cartan theory(EC), matter fields couple to gravitation field through the Minimal Coupling Procedure(MCP), yet leaving the theory an ambiguity: applying MCP to the action or to the equation of motion would lead to different gravitational couplings. We propose a new covariant derivative to remove the ambiguity, then discuss the relation between our proposal and previous treatments on this subject.

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Zi-Wei Chen, Run Diao, Xiang-Song Chen. 2019-12-06. On the Uniqueness of Einstein-Cartan Theory: Lagrangian, Covariant Derivative and Equation of Motion. https://arxiv.org/abs/1912.02987

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