This paper demonstrates that vacuum viscosity in the FUH model is not a regression to aether theory, but a manifestation of the quantum properties of space. We address criticisms regarding the fundamentality of viscous forces by showing they emerge naturally from the physics of a fermionic condensate. Instead of an empty void, we treat the vacuum as an ultradense quantum ocean (ψ-field). Using the framework of quantum hydrodynamics, we explain that viscosity is not an external "additive" to equations, but a macroscopic response of this medium. Quantum-Hydrodynamic Nature of Vacuum Viscosity in the FermionicUniverse Hypothesis (FUH).
Alexander Shlyapik (2026) studied this question.