[Draft] If space-time is considered as a kind of material, then what properties make sense? Properties that can be observed, measured. In the context of General relativity, (aggregate) properties related to curvature and rippling. Like elasticity, stiffness. In the context of quantum physics, (discrete) properties related to quanta, energy density, charge, spin, entanglement. Like gradients,… Continue reading How stiff is space-time?