Lorentz invariance measures the universal features in hypothetical loop quantum gravity universes. The various hypothetical multiverse loop quantum gravity universe design models could have various general covariant principle results. Because loop quantum gravity models universes, space gravity theories are contenders to build and answer unification theory; the Lorentz invariance helps grade the spread of universal features throughout a proposed multiverse in time. Grand Unification Epoch The Grand Unification Epoch is the era in time in the chronology of the universe where no elementary particles existed, and the three gauge interactions of the Standard Model which define the electromagnetic, weak, and strong interactions or forces, are merged into one single force. Convention says that 3 minutes after the Big Bang, protons and neutrons began to come together to form the nuclei of simple elements. Whereas, loop quantum gravity theories place the origin and the age of elementary particles and the age of Lorentz invariance, beyond 13.799 ± 0.021 billion years ago. The permanence of our Lorentz invariance constants is based on elementary particles and their features. There are eons of time before the Big Bang to build the universe from black holes and older multiverses. There is a selective process that creates features in elementary particles, like accept, store and give energy. In the books of Lee Smolin about loop quantum gravity, this theory contains the evolutionary ideas of "reproduction" and "mutation" of universes, and elementary particles, so is formally analogous to models of population biology. Earlier universes In the early universes before the Big Bang, there are theories that loop quantum gravity loop quantum structures formed space. The Lorentz invariance and universal constants describe elementary particles that do not exist yet. Fecund universes is a multiverse theory by Lee Smolin about the role of black holes. The theory 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 universe, 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. Minkowski spacetime Loop quantum gravity (LQG) is a quantization of a classical Lagrangian classical 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