2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/55379In the no-boundary univers e the universe is created from an instanton. However, there does not exist any instanton for the ``realistic'' $FRW$ universe with a scalar field. The ``instanton'' leading to its quantum creation may be modified and reinterpreted as a constrained gravitational instanton.5 pages, modifiedHigh Energy Physics - TheoryAstrophysicsGeneral Relativity and Quantum Cosmologytext