Plebanski action

General relativity and supergravity in all dimensions meet each other at a common assumption:

Using these assumptions one can construct an effective field theory in low energies for both. In this form the action of general relativity can be written in the form of the Plebanski action which can be constructed using the Palatini action to derive Einstein's field equations of general relativity.

The form of the action introduced by Plebanski is:

where

are internal indices,

is a curvature on the orthogonal group ${\displaystyle SO(3,1)}$ and the connection variables (the gauge fields) are denoted by

The symbol

is the Lagrangian multiplier and

is the antisymmetric symbol valued over ${\displaystyle SO(3,1)}$.

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