Quantum collision circuit, quantum invariants and quantum phase estimation procedure for fluid dynamic lattice gas automata

Lattice Gas Cellular Automata (LGCA) is a classical numerical method widely known and applied to simulate several physical phenomena. Among these phenomena, we find fluid flows described by the Navier-Stokes equations. We develop a quantum algorithm that allows for the simulation of fluid dynamic LGCA on a quantum computer. Furthermore, we prove the conservation of the quantities of interest, but finding more quantum invariants than expected. Finally, we develop a phase estimation procedure for detecting quantities of interest such as mass and momentum, avoiding reinitialization of the cell. In addition, we discuss a sublinear encoding of the lattice which admits a unitary streaming but constrains the collision step.