Slide 9

However, because we have no satisfactory supergrand unified theory, we can as yet say nothing about the nature of the universe during this period before the Planck time (t = 10–43 s after the Big Bang)
At the Planck time, gravity froze out to become a distinctive force in a spontaneous symmetry breaking
During a second spontaneous symmetry breaking, the strong nuclear force became a distinct force
This transition triggered the rapid inflation of the universe
A final spontaneous symmetry breaking separated the electromagnetic force from the weak nuclear force; from that moment on, the universe behaved as it does today

However, because we have no satisfactory supergrand unified theory, we can as yet say nothing about the nature of the universe during this period before the Planck time (t = 10–43 s after the Big Bang)