#big-bang

#big-bang

If the Universe is expanding and cooling today, that implies a past that was smaller, denser, and hotter. In our imaginations, we can extrapolate back to arbitrarily small sizes, high densities, and hot temperatures: all the way to a singularity, where all of the Universe's matter and energy was condensed in a single point. For many decades, these two notions of the Big Bang - of the hot dense state that describes the early Universe and the initial singularity - were inseparable.

According to physicists' best current theories, matter and its counterpart, antimatter, ought to have been created in equal amounts at the time of the Big Bang. But antimatter is vanishingly rare in the universe, raising questions about their behaviors that could explain this discrepancy.

The more curious we get about the great cosmic unknowns, the more unanswered questions our investigations of the Universe will reveal. Inquiring about the nature of anything - where it is, where it came from, and how it came to be - will inevitably lead you to the same great mysteries: about the ultimate nature and origin of the Universe and everything in it.

This is a unique opportunity to learn how the universe's first light emerged from the darkness. The transition from a cold, dark universe to one filled with stars is a story we're only beginning to understand.