Vacuum Localized Structures: Nonsingular Black Holes and Dark-Matter Candidates

Regular black-hole models featuring a de Sitter-like core have been proposed as a way to avoid curvature singularities within classical general relativity. In this work, we develop an alternative vacuum-based approach in which a black hole or compact object is supported by a Vacuum Localized Structure (VLS): a smooth, localized distribution of vacuum energy described by a Gaussian profile. The resulting spacetime has finite central density, a regular de Sitter-like interior, and an exterior that approaches the Schwarzschild solution. Energy-momentum conservation causes the localized vacuum to become anisotropic, yielding effective stresses similar to those in known regular black-hole and gravastar models. Depending on the mass and scale of the VLS, the geometry may contain two horizons or none, allowing for both regular black holes and horizonless ultracompact objects. Because the same vacuum structure can be extended to galactic scales, the VLS framework also offers a natural alternative to particle dark matter.