In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forces and gravitational waves (technically, these phenomena are the components of the Weyl tensor). <answer>The black hole</answer> (with zero electric charge) is an elegant example of a region completely "filled" with vacuum, but still showing a strong curvature.
what is a perfect example of a filled vacuum showing a curvature?
The black hole