Big Bang: an explosion of approximately 10^72 joules (give or take a joule). The date is estimated to be within +/- 110 million years. Before the Big Bang, the universe was completely empty, cold, and dark, but there was at least one speck of space with a vacuum, within which space began to expand dramatically, driven by the anti-gravity of vacuum energy. This was called “Guth’s Inflation.” The vacuum was an intuition of Alan Guth. Certain types of particles, under certain conditions, can spontaneously aggregate into a state he calls vacuum, which is part of the very fabric of space-time and contains energy, vacuum energy. The observable universe today is only the region of space in causal contact with us. For all we know, at the time of the Big Bang, the entire observable universe, within that speck of space, could have been enormous, even infinite. Before the Big Bang, the cosmic horizon contained regions of space vastly larger than today’s observable universe, but destined to escape beyond the horizon due to the astonishing expansion. The further back in time one goes, the vaster the space contained within the cosmic horizon. Nothing can transform into microscopic De Sitter space (discovered by Alexander Vilenking in the early 1980s), which Guth’s inflation then vastly expands. Nothing, filled with vacuum energy, is potentially capable of creating a universe as vast and complex as ours, and perhaps even a multiverse. Nothing creates the universe. The secret is a perfect cancellation between the positive contribution of vacuum energy and the negative contribution of gravitational energy. Despite appearances, in the universe all conserved physical quantities, including energy, add up to zero. Perhaps nothing is the explanation for everything.
