The big history of our world - from TED
From TED , I found this astonishing talk by David Christian (picture from global patriot.com): I n big history, you define a number of threshold moments, each of them creating slightly more complex things. Each stage is magical because it creates the impression of something utterly new appearing almost out of nowhere in the universe. These are the threshold stages , from a big history perspective : The Big Bang The Big Bang happens 13,7 billion (miljarder) years ago . The universe is tiny; it´s smaller than an atom. It contains everything that´s in today´s universe . The stars light up In the beginning there were only Hydrogen (H) and Helium (He). Eventually gravity started to build clouds of hydrogen and helium atoms. When the center of the clouds due to increased gravity crossed the threshold temperature of 10 million degrees, protons start to fuse, there´s a huge increase of energy. Bam - we have our first stars . This was about 200 million years after the Big Bang .