The energy quantization in hydrogen atom and proton–electron mass ratio in light of symmetrical special relativity

In this paper, we show the existence of an invariant minimum speed in space–time by forming the basis of a deformed special relativity so-called symmetrical special relativity (SSR). Such observer-independent minimum speed emerges from Dirac’s large number hypothesis (LNH), which leads us to build SSR-theory. This allows us to understand that the hydrogen atom represents the most stable bound state in the universe as being a fundamental structure of the symmetrical space–time with two limits of speed, namely the speed of light c and a minimum speed V. Such minimum speed is associated with a background reference frame for representing the vacuum energy related to the cosmological constant. So the symmetry in space–time given by the invariant minimum speed, which has origin in the electrical and gravitational bound states in hydrogen atom is able to provide a deeper understanding of the proton-electron mass ratio, i.e. [Formula: see text] given in terms of the universal minimum speed V. Furthermore, we investigate how the minimum speed in space–time plays a fundamental role in the quantization of energy in hydrogen atom.