Big Bang. Simon Singh

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СКАЧАТЬ contrast, in the Icelandic epic myth Prose Edda creation started not with an egg, but within the Yawning Gap. This void separated the contrasting realms of Muspell and Niflheim, until one day the fiery, bright heat of Muspell melted the freezing snow and ice of Niflheim, and the moisture fell into the Yawning Gap, sparking life in the form of Imir, the giant. Only then could the creation of the world begin.

      The Krachi people of Togo in West Africa speak of another giant, the vast blue god Wulbari, more familiar to us as the sky. There was a time when he lay just above the Earth, but a woman pounding grain with a long timber kept prodding and poking him until he raised himself above the nuisance. However, Wulbari was still within reach of humans, who used his belly as a towel and snatched bits of his blue body to add spice to their soup. Gradually, Wulbari moved higher and higher until the blue sky was out of reach, where it has remained ever since.

      For the Yoruba, also of West Africa, Olorun was Owner of the Sky. When he looked down upon the lifeless marsh, he asked another divine being to take a snail shell down to the primeval Earth. The shell contained a pigeon, a hen and a tiny amount of soil. The soil was sprinkled on the marshes of the Earth, whereupon the hen and pigeon began scratching and picking at it, until the marsh became solid ground. To test the world, Olorun sent down the Chameleon, which turned from blue to brown as it moved from sky to land, signalling that the hen and pigeon had completed their task successfully.

      Throughout the world, every culture has developed its own myths about the origin of the universe and how it was shaped. These creation myths differ magnificently, each reflecting the environment and society from which it originated. In Iceland, it is the volcanic and meteorological forces that form the backdrop to the birth of Imir, but according to the Yoruba of West Africa it is the familiar hen and pigeon that give rise to solid land. Nevertheless, all these unique creation myths have some features in common. Whether it is the big, blue, bruised Wulbari or the dying giant of China, these myths inevitably invoke at least one supernatural being to play a crucial role in explaining the creation of the universe. Also, every myth represents the absolute truth within its society. The word ‘myth’ is derived from the Greek word mythos, which can mean ‘story’, but also means ‘word’, in the sense of ‘the final word’. Indeed, anybody who dared to question these explanations would have laid themselves open to accusations of heresy.

      Nothing much changed until the sixth century BC, when there was a sudden outbreak of tolerance among the intelligentsia. For the very first time, philosophers were free to abandon accepted mythological explanations of the universe and develop their own theories. For example, Anaximander of Miletus argued that the Sun was a hole in a fire-filled ring that encircled the Earth and revolved around it. Similarly, he believed that the Moon and stars were nothing more than holes in the firmament, revealing otherwise hidden fires. Alternatively, Xenophanes of Colophon believed that the Earth exuded combustible gases that accumulated at night until they reached a critical mass and ignited, thereby creating the Sun. Night fell again when the ball of gas had burned out, leaving behind just the few sparks that we call stars. He explained the Moon in a similar way, with gases developing and burning over a twenty-eight-day cycle.

      The fact that Xenophanes and Anaximander were not very close to the truth is unimportant, because the real point is that they were developing theories that explained the natural world without resorting to supernatural devices or deities. Theories that say that the Sun is a celestial fire seen through a hole in the firmament or a ball of burning gas are qualitatively different from the Greek myth that explained the Sun by invoking a fiery chariot driven across the sky by the god Helios. This is not to say that the new wave of philosophers necessarily wanted to deny the existence of the gods, rather that they merely refused to believe that it was divine meddling that was responsible for natural phenomena.

      These philosophers were the first cosmologists, inasmuch as they were interested in the scientific study of the physical universe and its origins. The word ‘cosmology’ is derived from the ancient Greek word kosmeo, which means ‘to order’ or ‘to organise’, reflecting the belief that the universe could be understood and is worthy of analytical study. The cosmos had patterns, and it was the ambition of the Greeks to recognise these patterns, to scrutinise them and to understand what was behind them.

      It would be a great exaggeration to call Xenophanes and Anaximander scientists in the modern sense of the term, and it would flatter them to consider their ideas as full-blown scientific theories. Nevertheless, they were certainly contributing to the birth of scientific thinking, and their ethos had much in common with modern science. For example, just like ideas in modern science, the ideas of the Greek cosmologists could be criticised and compared, refined or abandoned. The Greeks loved a good argument, so a community of philosophers would examine theories, question the reasoning behind them and ultimately choose which was the most convincing. In contrast, individuals in many other cultures would not dare to question their own mythology. Each mythology was an article of faith within its own society.

      Pythagoras of Samos helped to reinforce the foundations of this new rationalist movement from around 540 BC. As part of his philosophy, he developed a passion for mathematics and demonstrated how numbers and equations could be used to help formulate scientific theories. One of his first breakthroughs was to explain the harmony of music via the harmony of numbers. The most important instrument in early Hellenic music was the tetrachord, or four-stringed lyre, but Pythagoras developed his theory by experimenting with the single-stringed monochord. The string was kept under a fixed tension, but the length of the string could be altered. Plucking a particular length of string generated a particular note, and Pythagoras realised that halving the length of the same string created a note that was one octave higher and in harmony with the note from the plucking of the original string. In fact, changing the string’s length by any simple fraction or ratio would create a note harmonious with the first (e.g. a ratio of 3:2, now called a musical fifth), but changing the length by an awkward ratio (e.g. 15:37) would lead to a discord.

      Once Pythagoras had shown that mathematics could be used to help explain and describe music, subsequent generations of scientists used numbers to explore everything from the trajectory of a cannonball to chaotic weather patterns. Wilhelm Röntgen, who discovered X-rays in 1895, was a firm believer in the Pythagorean philosophy of mathematical science, and once pointed out: ‘The physicist in preparing for his work needs three things: mathematics, mathematics and mathematics.’

      Pythagoras’ own mantra was ‘Everything is number.’ Fuelled by this belief, he tried to find the mathematical rules that governed the heavenly bodies. He argued that the movement of the Sun, Moon and planets across the sky generated particular musical notes, which were determined by the lengths of their orbits. Therefore, Pythagoras concluded, these orbits and notes had to have specific numerical proportions for the universe to be in harmony. This became a popular theory in its time. We can re-examine it from a modern perspective and see how it stands up to the rigours of today’s scientific method. On the positive side, Pythagoras’ claim that the universe is filled with music does not rely on any supernatural force. Also, the theory is rather simple and quite elegant, two qualities that are highly valued in science. In general, a theory founded on a single short, beautiful equation is preferred to a theory that relies on several awkward, ugly equations qualified by lots of complicated and spurious caveats. As the physicist Berndt Matthias put it: ‘If you see a formula in the Physical Review that extends over a quarter of a page, forget it. It’s wrong. Nature isn’t that complicated.’ However, simplicity and elegance are secondary to the most important feature of any scientific theory, which is that it must match reality and it must be open to testing, and this is where the theory of celestial music fails completely. According to Pythagoras, we are constantly bathed in his hypothetical heavenly music, but we cannot perceive it because we have been hearing it since birth and have become habituated to it. Ultimately, any theory that predicts a music that could never be heard, or anything else that could never be detected, is a poor scientific theory.

      Every genuine scientific theory must make a prediction about the universe that can be observed or measured. СКАЧАТЬ