Anti-de Sitter space bell. It might be described as being the "opposite" of the surface of a sphere, which has a positive curvature. General relativity is a theory of the nature of time, space and gravity in which gravity is a curvature of space and time that results from the presence of matter or energy. Energy and mass are equivalent (as expressed in the equation "E" = "mc"), and space and time can be translated into equivalent units based on the speed of light ("c" in the "E" = "mc" equation). A common analogy involves the way that a dip in a flat
Homogeneous differential equation rule: thus transforming the original differential equation into the separable form this form can now be integrated directly (see ordinary differential equation). The equations in this discussion are not to be used as formulary for solutions; they are shown just to demonstrate the method of solution. A first order differential equation of the form ("a", "b", "c", "e", "f", "g" are all constants) where "af" ≠ "be" can be transformed into a homogeneous type by a linear transformation of both variables (formula_17 and formula_18 are constants): A linear differential equation is homogeneous if it is a homogeneous linear equation in