>[!abstract] >Objective-collapse theories in quantum mechanics propose that the wavefunction does not merely reflect subjective knowledge but undergoes a real, physical collapse under certain conditions, independent of observation. Unlike the Copenhagen interpretation, which ties collapse to [[Measurement problem|measurement]], these theories posit mechanisms—such as spontaneous localization (GRW theory) or gravity-induced collapse (Penrose interpretation)—that trigger wavefunction reduction objectively. They aim to resolve the measurement problem by explaining how quantum superpositions give rise to definite outcomes, but at the cost of introducing new physical postulates that deviate from standard quantum dynamics. >[!related] >- **North** (upstream): [[Interpretations of quantum mechanics]] >- **West** (similar): [[Decoherence theory]] (explains appearance of collapse without invoking consciousness) >- **East** (different): [[Copenhagen interpretation]] (collapse as epistemic, tied to measurement/observation rather than objective physical process) >- **South** (downstream): [[GRW model]] (Ghirardi–Rimini–Weber spontaneous collapse theory)