Spectral Selection of the Cosmological Constant via an Instanton-Derived Effective Potential in Wheeler-DeWitt Quantum Cosmology

This work proposes a spectral selection mechanism for the cosmological constant within the framework of canonical quantum cosmology. By analyzing the Wheeler–DeWitt equation in the presence of an effective gravitational potential motivated by quantum corrections and vacuum structure, the cosmological constant is shown to arise as a discrete eigenvalue associated with normalizable quantum states of the universe. This formulation recasts the cosmological constant problem as a spectral problem in quantum gravity, suggesting that its observed value may correspond to a stable eigenmode of the underlying geometric operator. The results establish a mathematical framework linking vacuum energy, quantum cosmological stability, and eigenvalue selection, and provide a foundation for exploring the role of spectral structure in the global dynamics of spacetime and the emergence of physically realized universes.