Unit4-Albert-Einstein

Albert EinsteinGerman-born American Physicist and Nobel Laureate1879～1955“Imagination is more important than knowledge. ” ---- Albert EinsteinA Brief Introduction to Albert EinsteinAlbert Einstein, whose Special Theory of Relativity and General Theory of Relativity revolutionized scientific perceptions of the universe, is acknowledged, along with Newton, as one of history’s greatest physicists.Son of free-thinking, cultured Jews, Einstein was unable to speak until he was three and displayed no special promise. Anti-Semitism also hampered his talent when it began to emerge. He became a Swiss citizen in 1901, obtaining a doctorate from the University of Bern in 1905. His research, which ended in the famous equation E=mc2, was published in the same year.After World War I, Einstein’s fame extended beyond the scientific community and in 1921 he was awarded the Nobel Prize for physics. During the 1920s he regarded the rise of the Nazis in Germany with horror, eventually emigrating to the U.S. where, in 1933, he took up a post at Princeton University. In 1939 his early warnings of German scientific attempts to make an atomic bomb prompted the start of the Manhattan Project.•Einstein’s ChronologyTheory of Relativity1. A brief introductionIn 1905 Einstein received his doctorate from the University of Zurich for a theoretical dissertation on the dimensions of molecules, and he also published three theoretical papers of central importance to the development of 20th-century physics.On the basis of the General Theory of Relativity, Einstein accounted for the previously unexplained variations in the orbital motion of the planets and predicted the bending of starlight in the vicinity of a massive body such as the sun. The confirmation of this latter phenomenon during an eclipse of the sun in 1919 became a media event, and Einstein’s fame spread worldwide.2. Einstein explains the equivalence of energy and matter“It followed from the Special Theory of Relativity that mass and energy are both but different manifestations of the same thing — a somewhat unfamiliar conception for the average mind. Furthermore, the equation E is equal to mc squared, in which energy is put equal to mass, multiplied by the square of the velocity of light, showed that very small amounts of mass may be converted into a very large amount of energy and vice versa. The mass and energy were in fact equivalent, according to the formula mentioned before. This was demonstrated by Cockcroft and Walton in 1932, experimentally.”Atomic BombWhen Hitler came to power, Einstein immediately decided to leave Germany for the United States. He took a position at the Institute for Advanced Study at Princeton, New Jersey. In 1939 Einstein collaborated with several other physicists in writing a letter to President Franklin D. Roosevelt, pointing out the possibility of making an atomic bomb and the likelihood that the German government was embarking on such a course. The letter, which bore only Einstein’s signature, helped lend urgency to efforts in the U.S. to build the atomic bomb, but Einstein himself played no role in the work and knew nothing about it at the time.Fame and Social ActivitiesAfter 1919, Einstein became internationally renowned. He accrued honors and awards, including the Nobel Prize in physics in 1921, from various world scientific societies. His visit to any part of the world became a national event; photographers and reporters followed him everywhere.After the war, Einstein was active in the cause of international disarmament and world government but declined the offer made by leaders of the state of Israel to become president of that country. In the U.S. during the late 1940s and early 1950s he spoke out on the need for the nation’s intellectuals to make any sacrifice necessary to preserve political freedom. Einstein died in Princeton on April 18, 1955.The Yo-YoThe Yo-Yo is a simple toy consisting of a grooved double disk with a string about the center. The player holds the end of the string which unwinds itself as the disk is dropped. Then by a slight jerk on the string, the player causes it to rewind itself, and to reel up back to the hand. The toy is said to have originated in the Philippines. Since 1930 it has become a popular toy and even today children in different countries play the Yo-Yo and compete in various contests.The Nobel PrizeNobel Prizes are annual monetary awards granted to individuals or institutions for outstanding contributions in the fields of physics, chemistry, physiology or medicine, literature, international peace, and economic sciences. The Nobel Prizes are internationally recognized as the most prestigious awards in each of these fields. The prizes were established by Swedish inventor and industrialist Alfred Bernhard Nobel, who set up a fund for them in his will. The first Nobel Prizes were awarded on December 10, 1901, the fifth anniversary of Nobel’s death.Woolworth’sFrank Winfield Woolworth (1852~1919), an American merchant, was born in Rodman, New York. He established in 1879 a five-cent store at Utica, New York, which failed, and the same year he started a successful five-and-ten-cent store at Lancaster, Pennsylvania. Woolworth opened many others and soon extended business throughout the United States and to several foreign countries. In 1911 the F. W. Woolworth Company was incorporated with ownership of over 1,000 five-and-tens, and he became director of various financial firms. (The last Woolworth stores were closed in 1998.) Woolworth had the Woolworth Building erected in New York City in 1913, the highest building in the world (792 ft / 241.4 m) at that time.。