time-independent ("static") problems | time-dependent ("dynamical") problems | |

microscopic | use time-independent Schroedinger equation to obtain ground state, energy spectrum, etc. | use time-dependent Schroedinger equation to describe scattering processes, dynamics of wave packets, etc. |

macroscopic | use equilibrium statistical mechanics to obtain the equation of state, properties at phase transitions, heat capacity, etc. | need transport equations to describe
irreversible processes, macroscopic currents, flows, diffusion, relaxation,
dissipation, thermalization, etc. |