Claim: Numerical relativity, a branch of Einstein's general relativity, uses numerical methods and algorithms to solve and analyze problems, based upon the idea that space and time are a unified spacetime in Einstine field equations that form a set of coupled nonlinear partial differential equations.
Evidence: Numerical relativity is one of the branches of general relativity that uses numerical methods and algorithms to solve and analyze problems. Albert Einstein published his theory of general relativity in 1915. It, like his earlier theory of special relativity, described space and time as a unified spacetime subject to what are now known as the Einstein field equations. These form a set of coupled nonlinear partial differential equations (PDEs). After more than 100 years since the first publication of the theory, relatively few closed-form solutions are known for the field equations, and, of those, most are cosmological solutions that assume special symmetry to reduce the complexity of the equations. The field of numerical relativity emerged from the desire to construct and study more general solutions to the field equations by approximately solving the Einstein equations numerically.