A fantastic introduction to the possible ways in which the universe will end…
From one of the most dynamic rising stars in astrophysics, an accessible and eye-opening look at five ways the universe could end, and the mind-blowing lessons each scenario reveals about the most important concepts in cosmology.
We know the universe had a beginning. With the Big Bang, it expanded from a state of unimaginable density to an all-encompassing cosmic fireball to a simmering fluid of matter and energy, laying down the seeds for everything from black holes to one rocky planet orbiting a star near the edge of a spiral galaxy that happened to develop life as we know it. But what happens to the universe at the end of the story? And what does it mean for us now?
Dr. Katie Mack has been contemplating these questions since she was a young student, when her astronomy professor informed her the universe could end at any moment, in an instant. This revelation set her on the path toward theoretical astrophysics. Now, with lively wit and humor, she takes us on a mind-bending tour through five of the cosmos’s possible finales: the Big Crunch, Heat Death, the Big Rip, Vacuum Decay (the one that could happen at any moment!), and the Bounce. Guiding us through cutting-edge science and major concepts in quantum mechanics, cosmology, string theory, and much more, The End of Everything is a wildly fun, surprisingly upbeat ride to the farthest reaches of all that we know.
It has been a long time since I last took a science class — not just physics, but really any kind. I’ve kept my interest in the subject somewhat alive mainly through podcasts (for example, The Infinite Monkey cage, which is co-hosted by Brian Cox). Somehow, I managed to leave Katie Mack’s The End of Everything unread for quite some time. I started reading it late one night, and was hooked right from the start. This is an excellent book: one that should appeal to knowledgable scientists and the merely science-curious alike. I really enjoyed this. (And learned a lot!)
I won’t spend much time outlining what Mack covers in the book — and only partly because I don’t want to have misinterpreted anything. The first is an introduction to various key astrophysics concepts — how we are able to “see” the past, for example, how red- and blue-shift work, and various other important scientific concepts (and a little history) to make sure we’re all basically up-to-date for what it to come afterwards. It’s a very well-written chapter, and refreshed my memory nicely, as well as filled in many, many gaps that I’d allowed to build up.
We know it had a beginning. About 13.8 billion years ago, the universe went from a state of unimaginable density, to an all-encompassing cosmic fireball, to a cooling, humming fluid of matter and energy, which lay down the seeds for the stars and galaxies we see around us today. Planets formed, galaxies collided, light filled the cosmos. A rocky planet orbiting an ordinary star near the edge of a spiral galaxy developed life, computers, political science, and spindly bipedal mammals who read physics books for fun.
Mack starts with “the Big Crunch”, in which the universe would collapse in spectacular fashion if the current cosmic expansion were to reverse course. There are two chapters about dark-energy-driven apocalypses, in which the universe could continue expanding forever, slowly emptying and darkening; and one in which the universe just literally rips itself apart (“Dark-Energy-Driven Apocalypse” would be a great band name…). Vacuum decay is the next one, in which the spontaneous production of a “quantum bubble of death” devours the cosmos. In the final chapter of possible endings, the author describes and explains the speculative territory of “cyclic cosmology”, theories that include extra dimensions of space “in which our cosmos might be obliterated by a collision with a parallel universe… over and over again.” So, you know, it’s all pretty cheery stuff.
In all my readings, I have not yet found a serious suggestion in the current cosmological literature that the universe could persist, unchanged, forever.
Many times, it was almost as if Mack was predicting exactly the questions I would have, just as I had them. There were quite a few moments when, after I thought “Wait, hang on: what about…?”, the question was covered in the very next point. It’s a testament to how well-thought-out the book is, and Mack’s grasp of what reader questions might arise over the course of the explanations.
I thought the final chapter was also a rather nice touch. In it, Mack speaks to a number of other leading astrophysicists, who give their own opinions on this particular field of scientific study and theory. They are all uniformly enthusiastic about being alive and working at this time, to be able to study and investigate these incredible theories. To be able to look to the stars, and glimpse the beginning of the universe, and (less cheerfully) predict how it might all end. Here’s some of how Pedro Ferreira sees it:
“I think it’s great… I’ve never understood why people get so depressed about the end, the death of the Sun and all… I very much like our blip-ness… It’s the transience of these things. It’s the doing. It’s the process. It’s the journey. Who cares where you get to, right?”
This “blip-ness” is definitely something that came through, when reading The End of Everything. The sheer scale of the topic — be it the end of the universe, the Big Bang, the distances between the Earth and the moon, or other planets… it can really make one feel a rather insignificant. But then, I guess that’s part of the attraction of the subject: we are, indeed, quite insignificant on a universal scale. So, the fact that we — mere tiny bipeds on the third rock from this particular sun — can look up at the stars and detect what we can, is simply incredible. So, even though this is a book about the end, it is nevertheless quite uplifting and it’s certainly inspirational.
Overall, then, The End of Everything is a fascinating introduction to the most popular theories about how the universe might end. Not only that, though, Mack provides plenty of well-written, accessible explanations of some key astrophysics concepts. The author perfectly conveys complexity in an engaging and light way, without watering down the science. Mack is also clear to explain when certain concepts are just extrapolation, but explains these extrapolations clearly. I can’t claim to have understood everything fully, so I’ll have to revisit the book at some point in the near future. I will, however, do so very gladly.
Absolutely recommended to anyone with an interest in astrophysics and, of course, how everything is (probably) going to end.