Dynamics of 3-Forms in Seven Dimensions

We continue to study a certain dynamical theory of 3-forms in seven dimensions, which can be viewed as a non-linear 7D analog of the 3D Abelian Chern-Simons theory. We perform the 6+1 split and show that the theory propagates 3 degrees of freedom. We also study the dimensional reduction on S3. We find the resulting theory to be a variant of 4D scalar-tensor theory of gravity.