Big Bang and the Birth of the Universe

To this day, there are still countless theories, beliefs, and stories created seeking to explain our understanding of how the universe was created. Curiosity has been the main drive for all of these proofs, definitions, and beliefs. It has made our ancestors ponder “How old is the universe?”, “Who created it?”, and “How did we come to be?”. These complicated and hard-to-grasp questions have yet to be confirmed but our history on this planet has led to plausible explanations on the birth of our universe. Out of all the theories, explanations, and proofs that have been developed over the course of our history on this planet, the most popular and widely accepted explanation is the Big Bang Theory.

The Big Bang theory talks about how our universe started off as a small, hot, and infinitely dense point that exploded with unimaginable force to the ever expanding universe we know today over billions of years. The idea behind the big bang is that our universe started off with an explosion more than 14 billion years ago and that everything in our universe and possibly others, come from the same extremely dense point. According to the evidence presented by Georges Lemaitre in 1927, the universe is still expanding, even at this very second at 73 kilometers per second per megaparsec. Although the cause for this expansion is unknown and scientists have yet to prove this theory by peering back into the universe’s birth, much of our understanding comes from mathematical formulas and models. Much of the proof for this theory also stems from seeing the “echo” of this expansion, also known as the cosmic microwave background.

The cosmic microwave background (CBM) is leftover radiation from the Big Bang or when the universe began. As the theory goes, the universe went through periods of rapid inflation where the temperature of the universe was unimaginably high, to expansion, and to cooling phases where the temperature dropped drastically. The CBM represents the heat leftover from the Big Bang displayed through thermal energy coming from all parts of the sky. Although you can’t see CMB with your naked eye, with a sufficiently sensitive radio telescope, you can detect a faint background glow that is almost uniform and not associated with any star, planet, or other object in the universe. This radiation is often believed by most scientists as the “shockwave” for the explosion that is still visible around all planets, stars, galaxies, and galaxy clusters. Although the Big Bang Theory is the most plausible explanation for the birth of our universe, more evidence is expected to be discovered in the future about the birth of our universe and whether the Big Bang Theory is what caused our universe's birth.