Groebner-Shirshov bases for brace algebras

Let $A$ be a brace algebra. This structure implies that $A$ is also a pre-Lie algebra. In this paper, we establish Composition-Diamond lemma for brace algebras. Using this Composition-Diamond lemma we prove that each pre-Lie algebra $L$ can be embedded into a brace algebra $A_L$, i.e., $L$ is a pre-Lie subalgebra of $A_L$ up to isomorphism. We also determine an explicit linear basis for the brace algebra $A_{L}$.