Five Billion Years of Solitude Read Online Free PDF

China, the Middle East, and the Americas allarose independently and generally followed similar lines of development.
    And yet, the drivers of social change and technological progress were not at all clear. Despite China’s development of technologies such as gunpowder, compasses, paper, and the printing press hundreds of years before Europeans did, China experienced nothing equivalent to the European Renaissance and the successive scientific and industrial revolutions. When Spanish and Portuguese explorers, rather than the Chinese, used great ocean-faring ships to discover the Americas, they found indigenous civilizations using Stone Age technology that was no match for European steel and gunpowder. Sending ships across oceans or messages between the stars appeared to be a matter not only of technological prowess, but also of choice. Whether any given technological culture would attempt interstellar communication seemed unpredictable. Facing a somewhat arbitrary decision, the Green Bank attendees eventually guessed that between one-fifth and one-tenth of intelligent species would develop the capabilities and intentions to search for and signal other cosmic civilizations. That left only L , the typical lifetime of technological civilizations, for the group to consider.
    During a break in the proceedings, Drake noticed something that made him suspect his equation could be substantially streamlined: Three of the equation’s seven terms ( R , f l , f i ) appeared to be equal to one, and hence would have little effect on the product N , the number of detectable civilizations in our galaxy. Similarly, the plausible values of the other three terms ( f p , n e , f c ) could easily cancel each other out. For instance, the group had guessed that the average number of habitable planets per system, n e , was between one and five, and that f p , the fraction of stars with planets, was between one-half and one-fifth. If the value of n e was actually two, and f p ’s value was one-half, multiplied together the result was one, and N was scarcely affected. After considering the best evidence that was available, some of the brightest scientific minds on planet Earth had concluded that the universe, on balance, was a rather hospitable place, one that surely must be overflowing withliving worlds. It stood to reason that, on other planets circling other suns, other curious minds gazed at their night skies wondering if they, too, were alone. And yet, Drake announced, more than the number of stars, or the number of habitable planets, or how often life, intelligence, and high technology emerged, what he suspected really controlled the number of technological civilizations currently extant in the cosmos was almost solely their longevity. N = L .
    The thought made Morrison shudder. Of all the Green Bank attendees, he alone could viscerally appreciate just how fleeting our modern era might be. He had worked on the Manhattan Project during World War II, and had witnessed the detonation of the first atomic bomb, at Alamogordo, New Mexico, on July 16, 1945. A month later, on the South Pacific island of Tinian, Morrison had personally assembled and armed an atomic bomb that was later dropped on the Japanese city of Nagasaki. Tens of thousands of civilians were incinerated in the bomb’s fireball, and tens of thousands more died slowly from secondary burns and exposure to radioactive fallout, all from the nuclear fission of about two pounds of plutonium. When Japan’s surrender drew the war to a close, Morrison was among a contingent of American scientists who toured the cities of Hiroshima and Nagasaki to evaluate up close the devastation wrought by atomic warfare. Shortly after, he became a vocal proponent of nuclear disarmament, but it was too late. The Soviet Union had already begun a crash program to develop atomic bombs, and would successfully test its first nuclear weapon in 1949. In the ensuing arms race both the United States and the Soviet