A Cosmological Model Based on a Quadratic Equation of State Unifying Vacuum Energy, Radiation, and Dark Energy

Figure 1

Evolution of the scale factor 𝑎 with the time 𝑡 in logarithmic scales. This figure clearly shows the phase of inflation connecting the vacuum energy era to the radiation era. During the inflation, the scale factor increases by 29 orders of magnitude in less than 10⁻⁴²s. In the radiation era, 𝑎 increases algebraically.