# How to combine symmetrized tensor expressions into single expression in xAct

Let's sayI have the following expression in xAct

where covariant derivatives are commutative, $$\epsilon$$ and $$h$$ are symmetric tensors.

As we can see this expression is equivalent to

If we symmetrize it with respect to indices $$i,j,k,l$$

Is there any way to express the first expression like the second one with some sort of SymmetryGroup attached to it?

• Can you add how did you define the tensors h and epsilon? Did you add their symmetry there? It's important that you provide full, reproducible code. – jose Sep 15 '19 at 21:21