Force
Sir Isaac Newton described the motion of all objects using the concepts of inertia and force, and in doing so he found they obey certain conservation laws. In 1687, Newton published his thesis "Philosophiæ Naturalis Principia Mathematica". In this work Newton set out three laws of motion that to this day are the way forces are described in physics.
Anatoly Vlasov
Vlasov became world-famous for his work on plasma physics (1938) (see also ). He showed that the Boltzmann equation is not suitable for a description of plasma dynamics due to the existence of long range collective forces in the plasma. Instead, an equation known now as the Vlasov equation was suggested for the correct description to take into account the long range collective forces through a self-consistent field. The field is determined by taking moments of the distribution function described in Vlasov's equation to compute both the charge density and current density. Coupled with Maxwell's equations, the resulting system of differential equations are well-posed provided correct initial conditions and boundary conditions are provided.