Lawrence Krauss has an amazing voice.
I have never heard him speak, but the language of the book brought to mind one of those people who are incredibly good at following an idea through to its last implication, a little aware that they are better at this than most, and incredibly excited to share their results with any curious audience. You may only marginally be invested in a question you pose them, but within a couple minutes are completely engrossed in the narrative that is their answer.
The question in this case is easy to guess. How did our Universe come to be? We know today that it is expanding, which means that earlier in time, it must have been smaller. Following this back to the very ‘beginning’, the entire Universe – all of the galaxies, stars, planets, humans and animals and plants – must have fit in an unimaginably small point. But how did all this stuff get into that one point? How did space itself get into that point? There was no time before the beginning, either; where did time come from?
These are questions that the smartest minds of our time are still working on, but Krauss manages to communicate precisely why they are so interesting and the history of our attempts at answering them, assuming no background knowledge at all. There are photos and diagrams, yes, but there are also beer analogies. Politicians are used to explain the bizarre behaviour of quantum particles. And there you are, just under two hundred pages later, familiar with the cosmic microwave background, inflation, virtual particles, dark energy, dark matter, antimatter and the multiverse. All you need is the patience to follow some very neat logic, and trust two axioms – that anything that can happen, will; and that the simplest answer is probably correct.
On this point – that the Universe ultimately needs nothing more than (some rigorous) logic to be explained – Krauss is particular adamant. Throughout the book, he pauses at points commonly used as ‘proofs’ of the existence of Divine Creation; you can tell he’s heard these objections in person several times, and is presenting his own side pre-emptively. The most obvious, of course, is the titular question of where we all came from. Then there are points where the physical arguments seem wildly unrealistic, or appear to lose all predictive power. One of these arises in exploring the mystery of the cosmological constant, or the energy of empty space – it has a value embarrassingly different from any theoretical predictions. This has lead to the suggestion that there need not be a physical motivation for this; rather, a Universe could have had any value for this constant, but only the one observed in ours would allow the formation of astronomers to observe it in the first place. This means there is no reason for an infinite number of Universes to exist out there, causally disconnected from ours, with possibly very different physics. Krauss takes his sweet time clarifying why this conclusion is not contrary to the scientific approach, but inevitable from it. In short, he really wants you to know that science is still science and can get by just fine without religion.
I personally skipped half of that chapter, because that’s not what I came to the book for. What I sought was another concise narrative of the history of our Universe, with all its quirks, with all the beautiful and sometimes serendipitous ways humans have tried to uncover and then explain these quirks. And that I certainly found. This book is great for anyone, regardless of familiarity with physics or astronomy or of affinity for mathematics, who is curious about how the world we live in came to be.
