I have the following question. Provided that $E\to M$ is vector bundle and that a Clifford module $Cl(T^*M)$ acts on $\Gamma(E)$ via Clifford multiplication c,the dirac operator of this Clifford bundle is defined to be $$D = c \circ \nabla$$

If $x\in M$ and $e_1,...,e_n$ a local frame in $x\in U\subseteq M$, then the local form of the Dirac operator is said to be $$D = \sum_i c(e^i) \nabla_i$$

The question is: This equality holds everywhere in the local area U or only at the origin? And if it holds only at x why do we say "local can be written".

If we take a synchronous frame around x (we extend $e_1,...,e_n\in T_p M$ by parallel transport, along radial lines in a small area around x) then we can have that

$$\nabla s = \sum d(f_i) e_i + \sum f_i \nabla e_i$$ for $s = \sum f_i e_i$. but the second terms is zero only at x$$ It doesn't seem to hold in all points around x.

Anyone who can help?