Modern Times [antikvár]

ONE A Relativistic World The modern world began on 29 May 1919 when photographs of a solar echpse, taken on the island of Principe off West Africa and at Sobral in Brazil, confirmed the truth of a new theory of the universe. It had been apparent for half a century that the Newtonian cosmology, based upon the straight hnes of Euchdean geometry and Galileo's notions of absolute time, was in need of serious modification. It had stood for more than two hundred years. It was the framework within which the European Enlightenment, the Industrial Revolution, and the vast expansion of human knowledge, freedom and prosperity which characterized the nineteenth century, had taken place. But increasingly powerful telescopes were revealing anomalies. In particular, the motions of the planet Mercury deviated by forty-three seconds of arc a century from its predictable behaviour under Newtonian laws of physics. Why? In 1905, a twenty-six-year-old German Jew, Albert Einstein, then working in the Swiss patent office in Berne, had published a paper, 'On the electrodynamics of moving bodies', which became known as the Special Theory of Relativity. ^ Einstein's observations on the way in which, in certain circumstances, lengths appeared to contract and clocks to slow down, are analogous to the effects of perspective in painting. In fact the discovery that space and time are relative rather than absolute terms of measurement is comparable, in its effect on our perception of the world, to the first use of perspective in art, which occurred in Greece in the two decades c. 500-480 bc.^ The originality of Einstein, amounting to a form of genius, and the curious elegance of his lines of argument, which colleagues compared to a kind of art, aroused growing, world-wide interest. In 1907 he pubhshed a demonstration that all mass has energy, encapsulated in the equation E = mc^, which a later age saw as the starting point in the race for the A-bomb.^ Not even the onset of the European war prevented scientists from following his quest for an all-embracing f-, "ji