Fernández-Rañada, Antonio2023-06-202023-06-202009-060219-887810.1142/S0219887809003734https://hdl.handle.net/20.500.14352/44145© World Scientific Publishing. We acknowledge Dr. R. Tresguerres for useful discussions and to Dr. B. Coll for interesting suggestions on the intrinsic definition of the different classes. J. Martin is in debt to Junta de Castilla y León for the financial support.A general framework for the solutions of the constraints of pure gravity is constructed. It provides with well defined mathematical criteria to classify their solutions in four classes. Complete families of solutions are obtained in some cases. A starting point for the systematic study of the solutions of Einstein gravity is suggested.engGeneral structure of the solutions of the Hamiltonian constraints of gravityjournal articlehttp://dx.doi.org/10.1142/S0219887809003734http://www.worldscientific.comhttp://arxiv.org/abs/0709.0884open access537Gauge-TheoryRelativityFormulationVariablesSpin.ElectricidadElectrónica (Física)2202.03 Electricidad