The very early universe
Outline For the purposes of this summary, it is convenient to divide the chronology of the universe since it originated , into five parts. It is generally considered meaningless or unclear whether time existed before this chronology: The very early universe – the first picosecond (10 −12 ) of cosmic time. It includes the Planck epoch , during which currently understood laws of physics may not apply; the emergence in stages of the four known fundamental interactions or forces – first gravity , and later the strong , weak and electromagnetic interactions; and the expansion of space and supercooling of the still immensely hot universe due to cosmic inflation , which is believed to have been triggered by the separation of the strong and electroweak interaction . Tiny ripples in the universe at this stage are believed...