Invariance of the fine structure constant with temperature of the   expanding universe
  Our goal is to interpret the energy equation from Doubly Special Relativity (DSR) of Magueijo-Smolin with an invariant Planck energy scale in order to obtain the speed of light with an explicit dependence on the background temperature of the expanding universe. We also investigate how other universal constants, including the fine structure constant, have varied since the early universe and, thus, how they have evoluted over the cosmological time related to the temperature of the expanding universe. For instance, we show that both the Planck constant and the electron charge were also too large in the early universe. However, we finally conclude that the fine structure constant has remained invariant with the age and temperature of the universe, which is in agreement with laboratory tests and some observational data. 
Claudio Nassif and A. C. Amaro de Faria Jr
physics.gen-ph