Extended theories of gravity Extended theories of gravity Extended theories of gravity are alternative theories of gravity developed from the exact starting points investigated first by Einstein and Hilbert. These are theories describing gravity, which are metric theory, "a linear connection" or related affine theories, or metric-affine gravitation theory. Rather than trying to discover correct calculations for the matter side of the Einstein field equations; which include inflation, dark energy, dark matter, large-scale structure, and possibly quantum gravity; it is proposed, instead, to change the gravitational side of the equation. One such theory is also an extension to general relativity and Newton's Universal gravity
Lorentz invariance in loop quantum gravity has black holes and loop quantum gravity connecting early universes together. Loop quantum gravity can be pulled into black holes. In Fecund universes, each new universes, according to Lee Smolin, has slightly different laws of physics. Because these laws are only slightly different, each is assumed to be like a mutation of the early universes. Loop quantum gravity (LQG) is a quantization of a classical Lagrangian field theory. It is equivalent to the usual Einstein–Cartan theory in that it leads to the same equations of motion describing general relativity with torsion. As such, it can be argued that LQG respects