# Double covariant derivative of function of scalar

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1. Oct 9, 2015

### Prafulla Bagde

If R is Ricci scalar
∇i∇j F(R) = ??? , where ∇i is covariant derivative.

2. Oct 9, 2015

### Daeho Ro

Since $F(R)$ is scalar function, the first derivative is just ordinary gradient. But, after taking gradient, it now become a vector quantity and the second covariant acts on the vector quantity which will make some connection term.