Integration framework terms Links

The last term corresponds to the constant of integration asociated to the total energy of the sphere (and varies as a2). Its value depends on the initial conditions. Furthermore, it expresses a link between the geometry and the material content of the Universe, which cannot be specified in the Newtonian approach we had and can be justified only within the framework of GR. The form of the above equation is independent of the radius a of the sphere and we shall therefore admit that the equation still holds for the quantity li(t), the constant K being then the constant k which is involved in the Robertson-Walker metric element ... 

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