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Sunday, December 23, 2012

Isaac Newton_England

Isaac Newton
Born December 25, 1642 [January 4, 1643, New Style], Woolsthorpe, Lincolnshire, England—died March 20 [March 31], 1727, London, England. English physicist and mathematician, who was the culminating, figure of the scientific revolution of the 17th century. With discoveries in optics, motion,
and mathematics he developed the principles of modern physics. He was the original discoverer of the infinitesimal calculus. Newton's Philosophiae Naturalis Principia Mathematica ( Mathematical Principles of Natural Philosophy), 1687, was one of the most important single works in the history of modern science.

Early Life

On December 25, 1642, Isaac Newton was born in the hamlet of Woolsthorpe, England, the only son of a prosperous local farmer, also named Isaac Newton. Young Isaac never knew his father, who died three months before he was born. A premature baby born tiny and weak, Isaac was not expected to survive. When he was three, his mother, Hannah Ayscough Newton, remarried a well-do-do minister, Barnabas Smith, and went to live with him, leaving young Isaac with his maternal grandmother. The experience left an indelible imprint on Isaac which manifested itself later in life as an acute sense of insecurity. He anxiously obsessed over his published work and defended its merits with irrational behavior.

At age twelve, Isaac Newton was reunited with his mother after her second husband died. She brought along her three small children from her second marriage. Isaac had been enrolled at the King's School, Grantham, England, where he lodged with a local apothecary and was introduced to the fascinating world of chemistry. His mother pulled him out of school, for her plan was to make him a farmer and have him tend the farm. Isaac failed miserably for he found farming monotonous. He soon was returned to King's School to finish his basic education. Perhaps sensing his innate intellectual abilities, his uncle, a graduate of Trinity College at Cambridge persuaded Isaac's mother to have him enter the university. Isaac enrolled in 1661 in a program similar to a work study where he waited on tables and took care of wealthier students' rooms.
When Isaac Newton arrived at Cambridge, the scientific revolution was already in full force. The heliocentric view of the universe—theorized by astronomers Nicholas Copernicus and Johannes Kepler and later refined by Galileo Galilea—was well known in most European academic circles. Philosopher Rene Descartes had begun to formulate a new conception of nature as an intricate, impersonal, and inert machine. Yet, as with most universities in Europe, Cambridge was steeped in Aristotelian philosophy and view of nature resting on a geocentric view of the universe and dealing with nature in qualitative rather than quantitative terms.
During his first three years at Cambridge, Isaac Newton was being taught the standard curriculum but fascinated with the more advanced science. All his spare time was spent reading from the modern philosophers. The result was a less-than-stellar performance, but one that is understandable given his dual course of study. 
It was during this time that Newton kept a second set of notes entitled "Quaestiones Queedam Philosphicea" ("Certain Philosophical Questions"), begun sometime in 1664. The "Queaestiones" reveal that Newton had discovered the new conception of nature that provided the framework for the scientific revolution.
Though Isaac Newton graduated with no honors or distinctions, his efforts won him the title of scholar and four years of financial support for future education. Unfortunately, in 1665, the Great Plague that was ravaging Europe had come to Cambridge and the university closed. Newton returned home to pursue his private study. It was during this 18-month hiatus that he conceived the method of infinitesimal calculus, set foundations for his theory of light and color, and gained significant insight into the laws of planetary motion, insights that eventually led to the publication of his Principia in 1687. Legend has it that at this time Newton experienced his famous inspiration of gravity with the falling apple.
With the threat of plague subsided in 1667, Isaac Newton returned to Cambridge and was elected a minor fellow at Trinity College, still not considered a standout scholar. However, in the ensuing years, his fortune improved. Newton received his Master of Arts degree in 1669, before he was twenty-seven. During this time, he came across Nicholas Mercator's published book on methods for dealing with infinite series. Newton quickly wrote a treatise, De Analysi, expounding his own wider ranging results. He shared this with his friend and mentor Isaac Barrow but didn’t put his name as author. In June, 1669, Barrow shared the unaccredited manuscript with British mathematician John Collins. In August, 1669, Barrow indentified its author to Collins as "Mr. Newton… a very young… but of an extraordinary genius and proficiency in these things." Newton's work was brought to the attention of the mathematics community for the first time. Shortly afterwards, Barrow resigned his Lucasian Professorship at Cambridge and Newton assumed the Chair.

Professional Life

As professor, Isaac Newton was exempted from tutoring but required to deliver an annual course of lectures. He chose to deliver his work on optics as his initial topic. Part of his study in optics was aided with the use of a reflecting telescope that Newton designed and constructed in 1668, his first major public scientific achievement. This invention helped prove his theory of light and color. In 1671, the Royal Society asked for a demonstration of his reflecting telescope and their interest encouraged him to publish his notes On Colour in 1672, which he later revised to Book One of Opticks.
However, not everyone at the Royal Academy was enthusiastic about Isaac Newton's discoveries in optics. Among some of the dissenters was Robert Hooke, one of the original members of the Royal Academy and a scientist who was accomplished in a number of areas including mechanics and optics. In his paper, Newton theorized that white light was a composite of all the colors of the spectrum and that light was composed of particles. 
Hooke believed that light was composed of waves. Hooke quickly condemned Newton’s paper in condescending terms and attacked his methodology and conclusions. Hooke was not the only one to question Newton's work on optics. The great Danish scientist, Huygens and a number of French Jesuits also raised objections. But because of Hooke’s association with the Royal Society and his own work in optics, his criticism stung Newton the worst. He was unable to handle the critique and went into a rage, a reaction to criticism that was to continue throughout his life. He denied Hooke's charge that the theories had any shortcomings and argued the importance of his discoveries to all of science. In the ensuing months, exchange between the two men grew more acrimonious and soon Newton threatened to quit the Society altogether. He remained only when several other members assured him that the Fellows held him in high esteem. However, the rivalry with Hooke continued for several years afterward. Then, in 1678, Newton suffered a complete nervous breakdown and the correspondence abruptly ended. The death of his mother the following year completed his isolation and for six years he withdrew from intellectual exchange except when others initiated correspondence, which he always kept short.
During his hiatus from public life, Isaac Newton returned to his study of gravitation and its effects on the orbits of planets. Ironically, the impetus that put Newton on the right direction in this study came from Robert Hooke. In a 1679 letter of general correspondence to Royal Society members for contributions, Hooke wrote to Newton and brought up the question of planetary motion suggesting that a formula involving the inverse squares might explain the attraction between planets and the shape of their orbits. Subsequent exchanges transpired before Newton quickly broke off the correspondence once again. But Hooke's idea was soon incorporated into Newton's work on planetary motion and from his notes it appears he had quickly drawn his own conclusions by 1680, though he kept his discoveries to himself.
1n early 1684, in a conversation with fellow Royal Society members Christopher Wren and Edmund Halley, Hooke made is case on the proof for planetary motion. Both Wren and Halley thought he was on to something, but pointed out that a mathematical demonstration was needed. In August, 1684, Halley traveled to Cambridge to visit with Newton, who was coming out of his seclusion. Halley idly asked him what shape the orbit of a planet would take if its attraction to the sun followed the inverse square of the distance between them (Hooke’s theory). Newton knew the answer due to his concentrated work for the past six years and replied "an ellipse." Newton claimed to have solved the problem some eighteen years ago during his hiatus from Cambridge and the plague, but he was unable to find his notes. Halley persuaded him to work out the problem mathematically and offered to pay all costs so that the ideas might be published.

Publishing Principia

In 1687, after eighteen months of intense and effectively nonstop work, Newton published Philosophiae, Natrualis, Principia Mathematica (The Mathematical Principles of Natural Philosophy). Said to be the most single influential book on physics and possibly all of science, it is most often known as Principia and contains nearly all the essential concepts of physics, except energy. The work offers an exact quantitative description of bodies in motion in three basic laws: 1) a stationary body will stay stationary unless an external force is applied to it; 2) force is equal to mass times acceleration and a change in motion is proportional to the force applied; 3) for every action there is an equal and opposite reaction. These three laws not only helped explain elliptical planetary orbits but nearly every other motion in the universe: how the planets are kept in orbit by the pull of the sun’s gravity; how the moon revolves around earth and the moons of Jupiter revolve around it; how comets revolve in elliptical orbits around the sun. The laws also allowed Newton to calculate the mass of each planet, calculate the flattening of the Earth at the polls and the bulge at the equator, and how gravitational pull of the sun and moon create the Earth’s tides. In Newton's account, the force he called gravity, kept the universe balanced, made it work, and brought heaven and earth together in one great equation.
Upon the publication of the first edition of Principia, Robert Hooke immediately accused Newton of plagiarism, claiming he had discovered the theory of inverse squares. The charge was unfounded, as most scientists knew, for Hooke had only theorized on the idea and had never brought it to any level of proof. However, Newton was furious and strongly defended his discoveries. He withdrew all references to Hooke in his notes and threatened to withdraw from publishing the subsequent edition of Principia altogether. Halley had invested much of himself in Newton’s work and tried to make peace between the two men. While Newton begrudgingly agreed to insert a joint acknowledgement of Hooke’s work (shared with Wren and Halley) in his discussion of the law of inverse squares, it did nothing to placate Hooke. As the years went on, Hooke's life began to unravel. His beloved niece and companion died the year Principia was published. As Newton's reputation and fame grew, Hooke's declined and he grew even more bitter and loathsome toward his rival. To the bitter end, Hooke took every opportunity he could to offend Newton. Knowing that is rival would soon be elected president of the Society, Hooke refused to retire until his death in 1703.

International prominence

The Principia immediately raised Isaac Newton to international prominence and he became more involved in public affairs. Consciously or unconsciously he was ready for a new direction in life. He no longer found contentment in his position at Cambridge and he was becoming more involved in other issues.
He helped lead the resistance to King James II’s attempts to reinstitute Catholic teaching at Cambridge and in 1689, he was elected to represent Cambridge in Parliament. While in London, Newton acquainted himself with a broader group of intellectuals and became acquainted with political philosopher John Locke. Though many of the scientists on the continent continued to teach the mechanical world according to Aristotle, a young generation of British scientists became captivated with Newton’s new view of the physical world and recognized him as their leader. One of these admirers was Nicholas Fatio de Duillier, a Swiss-born mathematician who Newton befriended while in London.
However, within a few years Newton fell into another nervous breakdown in 1693. The cause is open to speculation: overwork, his disappointment over not being appointed to a higher position by England's new monarchs William and Mary, the subsequent loss of his friendship with Duillier, or perhaps chronic mercury poisoning after decades of alchemical research. It's difficult to know the exact cause, but evidence suggests that letters written by Newton to several of his London acquaintances and friends, including Duillier, seemed deranged and paranoiac and accused them of betrayal and conspiracy. Oddly enough, Newton recovered quickly, wrote letters of apology to friends, and was back to work within a few months. He emerged with all his intellectual facilities intact, but seemed to have lost interest in scientific problems and now favored pursuing prophecy and scripture and the study of alchemy. While some might see this as work beneath the man who had revolutionized science, it might be more attributed to Newton responding to the issues of the time in turbulent 17th century Britain. Many intellectuals were grappling with the meaning of many different subjects, not least of which were religion, politics, and the very purpose of life. Modern science was still so new, no one knew for sure how it measured up against older philosophies.
In 1696, Isaac Newton was able to attain the governmental position he had long sought, Warden of the Mint. He permanently moved to London and lived with his niece, Catherine Barton. She was the mistress of Lord Halifax, a high-ranking government official who was instrumental in having Newton promoted to Master of the Mint in 1699, a position he would hold until his death. Not to be considered a mere honorary position, Newton approached the job with earnest, reforming the currency and severely punishing counterfeiters. As Master of the Mint, Newton moved the British currency, the Pound Sterling, from the silver to the gold standard.
In 1703, Newton was elected president of the Royal Society upon Robert Hooke’s death. In 1705, he was knighted by Queen Anne. At this point in his life, Isaac Newton's career in science and discovery had given way to a career of political power and influence. Newton never seemed to understand the notion of science as a cooperative venture and his own ambition and fierce defense of his own discoveries continued to lead him from one conflict after another with other scientists.
By most accounts, Newton's tenure at the Society was tyrannical and autocratic. He was able to control the lives and careers of younger scientists with absolute power. In 1705, in a controversy that had been brewing for several years, German mathematician Gottfried Liebniz publically accused Newton of plagiarizing his research, claiming he had discovered infinitesimal calculus several years before the publication of Principia. In 1712 the Royal Society appointed a committee to investigate the matter. Of course, with Newton as president, he was able to appoint the committee members and oversee its investigation. Not surprisingly, the committee concluded Newton’s priority over the discovery.
That same year, in another of Isaac Newton's more flagrant episodes of tyranny, he published without permission the notes of astronomer John Flamsteed. It seems the astronomer had collected a massive body of data from his years at the Royal Observatory at Greenwich, England. Newton had requested a large volume of Flamsteed's notes for his revisions to Principia. Annoyed when Flamsteed wouldn’t provide him more information as quickly as he wanted it, Newton used his influence as president of the Royal Society to be named the chairman of the body of “visitors” responsible for the Royal Observatory. Then he tried to force the immediate publication of Flamsteed's catalogue of the stars, all of Flamsteed’s notes, edited and unedited. To add insult to injury, Newton arranged for Flamsteed's mortal enemy Edmund Halley, to prepare the notes for press. Flamsteed was finally able to get a court order to have Newton cease his plans for publication and return the notes back to him, one of the few times Newton was bested by one of his rivals.

Final Years

Towards the end of this life, Isaac lived at Cranbury Park, near Winchester with his niece, Catherine Conduitt, and her husband. He was one of the most famous men in Europe. His scientific discoveries were unchallenged. He also had become wealthy, investing his sizeable income wisely and bestowing sizeable gifts to charity. He never married nor made many friends. In his later years a combination of pride, insecurity, and side-trips on peculiar scientific inquiries led even some of his few friends to worry about his mental stability. By the time he reached eighty years of age, he was experiencing digestion problems and had to drastically change his diet and mobility. On March 19, 1727 he experienced severe pain in his abdomen and blacked out, never to regain consciousness. He died the next day at age eighty-five. His fame grew even more after his death as many of his contemporaries proclaimed him the greatest genius that ever lived. Maybe a slight exaggeration, but his discoveries had an impact on Western thought that can be compared with figures like Plato, Aristotle, and Galileo. Although his discoveries were among many made during the Scientific Revolution, his universal principles of gravity found no parallels in science at the time. Of course, Newton was proven wrong on some of his key assumptions. In the 20th century, Albert Einstein would overturn Newton's concept of the universe, stating that space, distance, and motion were not absolute but relative and that the universe was more fantastic than Newton ever conceived. Newton himself may not have been surprised. In his later life, when asked for an assessment of his achievements, he replied, "I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself now and then in finding a smoother pebble or prettier shell than ordinary, while the great ocean of truth lay all undiscovered before me."

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