Just six numbers

Astronomy is the oldest numerical science, crucial in ancient times for calendars and navigation. It is now experiencing a surge of discovery. The enhanced focus on time as we enter the new millennium is boosting interest in our cosmic environment. Astronomy is still the science of numbers, and this book is the story of six that are crucial for our universe, and our place in it. On the blurred boundaries of ancient maps, cartographers wrote ‘There be dragons’. After the pioneer navigators had encircled the globe and delineated the main continents and oceans, later explorers filled in the details. But there was no longer any hope of finding a new continent, or any expectation that the Earth’s size and shape would ever be drastically reappraised. At the end of the twentieth century we have, remarkably, reached the same stage in mapping our universe: the grand outlines are now coming into focus. This is the collective achievement of thousands of astronomers, physicists and engineers, using many different techniques. Modern telescopes probe deep into space; because the light from distant objects takes a long time journeying towards us, they also give us glimpses of the remote past; we have detected ‘fossils’ laid down in the first few seconds of cosmic history. Spacecraft have revealed neutron stars, black holes, and other extreme phenomena that extend our knowledge of the physical laws. These advances have vastly stretched our cosmic horizons. There has, in parallel, been an exploration of the microworld within the atom, yielding new insights into the nature of space on the tiniest of scales. The picture that emerges — a map in time as well as in space — is not what most of us expected. It offers a new perspective on how a single ‘genesis event’ created billions of galaxies, black holes, stars and planets, and how atoms have been assembled — here on Earth, and perhaps on other worlds — into living beings intricate enough to ponder their origins. There are deep connections between stars and atoms, between the cosmos and the microworld. This book describes — without technicalities — the forces that control us and, indeed, our entire universe. Our emergence and survival depend on very special ‘tuning’ of the cosmos — a cosmos that may be even vaster than the universe that we can actually see.