Most scientists believe that our Universe was born roughly 13.7 billion years ago, along with the biggest event of all: the Big Bang. At first, all matter, space, and time were crammed into a very small singularity that apparently came from nowhere.
Although there are plenty of questions here without a response, scientists rely on the Big Bang Theory for a few reasons. Einstein’s General Relativity backs it up, the fact that our Universe is constantly expanding hints that everything must have started from a single point, and last but not least: the cosmic microwave background radiation discovered by two astronomers named Penzias and Wilson in 1963 is considered the strongest evidence that our Universe expanded from an initial violent “explosion”.
The Universe can end in many ways
Everyone knows now that the Universe had a beginning. Not only science claims it – the Bible teaches us the same thing through its very first verse. But even our limited common sense as human beings teaches us that the Universe will also end someday, and again, science agrees with that. Sure, it would be a comfortable feeling knowing that although each of us will die someday, the Universe will live on forever. But unfortunately, the laws of nature don’t give an atom about what we want.
Katherine J. Mack (commonly known as Katie Mack) is a 40-year-old theoretical cosmologist and Assistant Professor from North Carolina State University. Her academic research investigates vacuum decay, dark matter, as well as the epoch of reionisation.
Katie Mack explains for The Big Issue publication the ways the Universe can end, and unfortunately, there are plenty of methods to destroy our physical reality. However, such a scenario is likely very far away into the future, meaning that each of us will have plenty of time to reach his highest goals or fail completely while trying. The scientist begins her speech in the following way, as quoted by The Big Issue:
I am not in any way a morbid person.
The concept of death, in general, is not something I’ve ever made peace with. I am perfectly happy to assume that I, all my loved ones, and everybody’s pets, are immortal, destined to live, peacefully, forever. This illusion has become rather difficult to maintain, however, now that a significant part of my professional life is focused on the inevitable destruction of the universe itself.
Katie Mack explains that if we compare the number of stars that the Universe has created until now to the number of stars that will emerge in the future, the conclusion is that our Universe is around 90% finished.
The best-case scenario for our Universe’s demise, according to Katie Mack, is the transition into a so-called “Heat Death”, meaning that our Cosmos will become dark, cold, and empty. The scientist says that the process is already in progress, although it will need a very long timespan to become complete. What happens in this scenario is that along with the Universe’s expansion, galaxies will depart more and more from one another, as the matter will become more and more diffuse.
If somebody somehow finds the secret for eternal youth, he’ll see that 100 billion years from now, other galaxies won’t be visible anymore. Furthermore, most of the stars from our own Milky Way galaxy will burn out.
Until only about a century ago, most astronomers believed that the Universe is eternal, with no beginning nor end. But it was thanks to the astronomer Edwin Hubble’s discoveries from the 1920s that scientists began to have a different view. It’s amazing how much science has advanced in all this time!
Feel free to read Katie Mack’s full article on The Big Issue publication!