Extend the propagating-gravitational-wave framework beyond its idealized assumptions

Extend the quantum-detector framework for propagating gravitational waves to coherent and non-Gaussian gravitational-wave states, stochastic cosmological graviton backgrounds, realistic environmental decoherence, and nonlinear gravitational interactions beyond the linearized approximation.

Background

The framework is developed using linearized General Relativity, a perturbative detector–field interaction, and an effective single-mode description. The authors explicitly identify several extensions that remain unresolved: treating more general initial gravitational states, incorporating cosmological graviton backgrounds, modelling environmental decoherence, and going beyond linearized gravitational interactions. These extensions are intended to assess the robustness and physical relevance of the predicted entanglement and other nonclassical correlations in more realistic settings.