Max Planck

SCIENTIST

Max Planck Max Karl Ernst Ludwig Planck was born on 23 April in Kiel Germany. He was the sixth child in a family devoted to the church and state. His father was a prominent jurist and professor of law at the University of Kiel. At the age of 9, his father received a post at the University of Munich, and Planck attended the Maximilian Gymnasium. While there Planck succeeded very well in all subjects and he gained an interest in physics and mathematics finally graduating at the age of 17. He found it difficult to make a decision on what career he was going to aim for, finally settling for physics rather than music or classical philogy, since he believed he had his greatest originality within that physics. He was an excellent pianist and found great pleasure in playing, having the gift of absolute pitch. Another passion of his was hiking, mountain climbing and taking long walks as regularly as possible. Planck based his doctoral dissertation on the second law of thermodynamics and in July 1879, at the young age of 21 he received his doctoral degree. Following this he completed his qualifying dissertation at Munich and he employed as a lecturer (Privatdozent). With the help of his father in 1885 he took up the position of associate professor at the University of Kiel becoming a full professor in 1892 at the University of Berlin when Kirchoff died. Planck lectured on all branches of theoretical physics and had nine doctoral students study under him. Planck was intrigued by the law discovered by his colleague Wilhelm Wien in 1896. He made several attempts at deriving this law, starting from the second law of thermodynamics as a base Experimental evidence was coming to light which showed that Wiens law broke down completely at low frequencies but was perfectly viable at high frequencies. Plank guessed that, since the entropy of radiation depended mathematically on it's energy in the high frequency range due to Wiens law, and that because he knew what the dependance was in the low frequency region, he should somehow combine these two properties in some simple manner resulting in a formula relating frequency, to the energy of radiation. The formula was hailed a great success, but Planck noted that it was just a formula; a lucky guess which still had to be derived from first principles inorder to give it a proper scientific standing. In 1900, at the age of 42, Planck achieved this, but in the process he had to abandon one of his greatest beliefs - that the second law of thermodynamics was an absolute law of nature. He was forced to accept Ludwig Boltzmann's statistical explanation for the second law. Planck also had to assume that the black body oscillators could only absorb and emit energy in discrete amounts of energy - packets of energy which he called quanta. Only by carrying out a statistical analysis of these quanta of energy could Planck derive his formula. Each quanta contained an energy directly proportional to a constant, h, multiplied by the frequency of oscillation of the particular blackbody oscillator associated with that quanta. Using his formula he calculated a value for Boltzmanns constant, Avogadros numer, the charge of the electron as well as the constant h. As time passed others came to realise that because of the finite, non-zero value of h, the world at atomic dimensions could not be explained with classical mechanics. The quantum age had truly begun! Planck was very reluctant to introduce his revolutionary idea on the quantisation of energy, and only by being forced by pure logic did he do so. It took a number of years before Planck's ideas were generally recognised and it was the likes of Einstein, Bohr and Poincare who developed the quantum idea further in the early half of the century. In 1912 Planck became the permanent

SCIENTIST

scretary of the mathematics and physics sections of the Prussian Academy of Sciences and continued to hold the post until 1938. In 1918 he received the Nobel Prize for Physics for his work on introducing the quantum. Along side Einstein and Schrodinger, he sternly opposed the statistical view held by Bohr, Born, Heisenberg and many others which was introduced to quantum mechanics in 1925-26. Planck retired in 1928, with Erwin Shrodinger taking his place until the Nazis took power in 1933. In 1930 Planck became the president of the Kaiser Wilhelm society (now known as the Max Planck Society) until 1937. Planck suffered many personal tragedies, including losing two sons and daughters at an early age. One of his sons, Erwin, was killed by the Gestapo due to a failed bombing of Hitler in 1944. This incident left Planck without the will to live. He died on the 4th October, 1947 aged 89.

Thomas Alva Edison Thomas Alva Edison (February 11, 1847 - Oct. 18, 1931) was an American inventor who, singly or jointly, held a world record 1,093 patents. In addition, he created the world's first industrial research laboratory. Edison was the quintessential American inventor in the era of Yankee ingenuity. He began his career in 1863, in the adolescence of the telegraph industry, when virtually the only source of electricity was primitive batteries putting out a low-voltage current. Before he died, in 1931, he had played a critical role in introducing the modern age of electricity. From his laboratories and workshops emanated the phonograph, the carbon-button transmitter for the telephone speaker and microphone, the incandescent lamp, a revolutionary generator of unprecedented efficiency, the first commercial electric light and power system, an experimental electric railroad, and key elements of motion-picture apparatus, as well as a host of other inventions. Edison was the seventh and last child--the fourth surviving--of Samuel Edison, Jr., and Nancy Elliot Edison. At an early age he developed hearing problems, which have been variously attributed but were most likely due to a familial tendency to mastoiditis. Whatever the cause, Edison's deafness strongly influenced his behaviour and career, providing the motivation for many of his inventions. Menlo Park Although Edison was a sharp bargainer, he was a poor financial manager, often spending and giving away money more rapidly than he earned it. In 1871 he married 16-year-old Mary Stilwell, who was as improvident in household matters as he was in business, and before the end of 1875 they were in financial difficulties. To reduce his costs and the temptation to spend money, Edison brought his now-widowed father from Port Huron to build a 2 1/2-story laboratory and machine shop in the rural environs of Menlo Park, N.J.--12 miles south of Newark--where he moved in March 1876. Accompanying him were two key associates, Charles Batchelor and John Kruesi. Batchelor, born in Manchester in 1845, was a master mechanic and draftsman who complemented Edison perfectly and served as his "ears" on such projects as the phonograph and telephone. He was also responsible for fashioning the drawings that Kruesi, a Swiss-born machinist, translated into models. Edison experienced his finest hours at Menlo Park. While experimenting on an underwater cable for the automatic telegraph, he found that the electrical resistance and conductivity of carbon (then called plumbago) varied according to the pressure it was under.

SCIENTIST

This was a major theoretical discovery, which enabled Edison to devise a "pressure relay" using carbon rather than the usual magnets to vary and balance electric currents. In February 1877 Edison began experiments designed to produce a pressure relay that would amplify and improve the audibility of the telephone, a device that Edison and others had studied but which Alexander Graham Bell was the first to patent, in 1876. By the end of 1877 Edison had developed the carbon-button transmitter that is still used in telephone speakers and microphones. The phonograph Edison invented many items, including the carbon transmitter, in response to specific demands for new products or improvements. But he also had the gift of serendipity: when some unexpected phenomenon was observed, he did not hesitate to halt work in progress and turn off course in a new direction. This was how, in 1877, he achieved his most original discovery, the phonograph. Because the telephone was considered a variation of acoustic telegraphy, Edison during the summer of 1877 was attempting to devise for it, as he had for the automatic telegraph, a machine that would transcribe signals as they were received, in this instance in the form of the human voice, so that they could then be delivered as telegraph messages. (The telephone was not yet conceived as a general, person-to-person means of communication.) Some earlier researchers, notably the French inventor Léon Scott, had theorized that each sound, if it could be graphically recorded, would produce a distinct shape resembling shorthand, or phonography ("sound writing"), as it was then known. Edison hoped to reify this concept by employing a stylus-tipped carbon transmitter to make impressions on a strip of paraffined paper. To his astonishment, the scarcely visible indentations generated a vague reproduction of sound when the paper was pulled back beneath the stylus. Edison unveiled the tinfoil phonograph, which replaced the strip of paper with a cylinder wrapped in tinfoil, in December 1877. It was greeted with incredulity. Indeed, a leading French scientist declared it to be the trick device of a clever ventriloquist. The public's amazement was quickly followed by universal acclaim. Edison was projected into worldwide prominence and was dubbed the Wizard of Menlo Park, although a decade passed before the phonograph was transformed from a laboratory curiosity into a commercial product. The electric light This was a time when great advances were being made in electric arc lighting, and during the expedition, which Edison accompanied, the men discussed the practicality of "subdividing" the intense arc lights so that electricity could be used for lighting in the same fashion as with small, individual gas "burners." The basic problem seemed to be to keep the burner, or bulb, from being consumed by preventing it from overheating. Edison thought he would be able to solve this by fashioning a microtasimeter-like device to control the current. He boldly announced that he would invent a safe, mild, and inexpensive electric light that would replace the gaslight. The incandescent electric light had been the despair of inventors for 50 years, but Edison's past achievements commanded respect for his boastful prophecy. Thus, a syndicate of leading financiers, including J.P. Morgan and the Vanderbilts, established the Edison Electric Light Company and advanced him $30,000 for research and development. Edison proposed to connect his lights in a parallel circuit by subdividing the current, so that, unlike arc lights, which were connected in a series circuit, the failure of one light bulb would not cause a whole circuit to fail. Some eminent scientists predicted that such a circuit could never be feasible, but their findings were based on systems of lamps with low resistance - the only successful type of electric light at the time. In 1881-82 William J. Hammer, a young engineer in charge of testing the light globes, noted a blue glow around the positive pole in a vacuum bulb and a blackening of the wire and the bulb at

SCIENTIST

the negative pole. This phenomenon was first called "Hammer's phantom shadow," but when Edison patented the bulb in 1883 it became known as the "Edison effect."

Albert Einstein Albert Einstein was a German-born theoretical physicist who is widely considered one of the greatest physicists of all time. While best known for the theory of relativity (and specifically mass-energy equivalence, E=mc2), he was awarded the 1921 Nobel Prize in Physics for his 1905 (Annus Mirabilis) explanation of the photoelectric effect and "for his services to Theoretical Physics". In popular culture, the name "Einstein" has become synonymous with great intelligence and genius. Einstein was named Time magazine's "Man of the Century." He was known for many scientific investigations, among which were: his special theory of relativity which stemmed from an attempt to reconcile the laws of mechanics with the laws of the electromagnetic field, his general theory of relativity which extended the principle of relativity to include gravitation, relativistic cosmology, capillary action, critical opalescence, classical problems of statistical mechanics and problems in which they were merged with quantum theory, leading to an explanation of the Brownian movement of molecules; atomic transition probabilities, the probabilistic interpretation of quantum theory, the quantum theory of a monatomic gas, the thermal properties of light with a low radiation density which laid the foundation of the photon theory of light, the theory of radiation, including stimulated emission; the construction of a unified field theory, and the geometrization of physics. Works and Doctorate Einstein could not find a teaching post upon graduation, mostly because his brashness as a young man had apparently irritated most of his professors. The father of a classmate helped him obtain employment as a technical assistant examiner at the Swiss Patent Office[8] in 1902. His main responsibility was to evaluate patent applications relating to electromagnetic devices. He also learned how to discern the essence of applications despite sometimes poor descriptions, and was taught by the director how "to express [him]self correctly". He occasionally corrected their design errors while evaluating the practicality of their work. His friend from Zurich, Michele Besso, also moved to Bern and took a job at the patent office, and he became an important sounding board. Einstein also joined with two friends he made in Bern, Maurice Solovine and Conrad Habicht, to create a weekly discussion club on science and philosophy, which they grandly and jokingly named "The Olympia Academy." Their readings included Poincare, Mach, Hume, and others who influenced the development of the special theory of relativity. Einstein married Mileva Maric on January 6, 1903. Einstein's marriage to Maric who was a mathematician, was both a personal and intellectual partnership: Einstein referred to Mileva as "a creature who is my equal and who is as strong and independent as I am". Ronald W. Clark, a biographer of Einstein, claimed that Einstein depended on the distance that existed in his marriage to Mileva in order to have the solitude necessary to accomplish his work; he required intellectual isolation. In an obituary of Einstein Abram Joffe wrote: "The author of [the papers of 1905] wasŠ a bureaucrat at the Patent Office in Bern, Einstein-Maric which has been taken as evidence of a collaborative relationship. However, most probably Joffe referred to EinsteinMaric ecause he believed that it was a Swiss custom at the time to append the spouse's surname to the husband's name. The extent of her influence on Einstein's work is a controversial and debated question.

SCIENTIST

In 1903, Einstein's position at the Swiss Patent Office had been made permanent, though he was passed over for promotion until he had "fully mastered machine technology". He obtained his doctorate under Alfred Kleiner at the University of Zürich after submitting his thesis "A new determination of molecular dimensions" ("Eine neue Bestimmung der Moleküldimensionen") in 1905. During 1905, in his spare time, he wrote four articles that participated in the foundation of modern physics, without much scientific literature he could refer to or many fellow scientists with whom he could discuss the theories. Most physicists agree that three of those papers (on Brownian motion, the photoelectric effect, and special relativity) deserved Nobel Prizes. Only the paper on the photoelectric effect would be mentioned by the Nobel committee in the award; at the time of the award, it had the most unchallenged experimental evidence behind it, although the Nobel committee expressed the opinion that Einstein's other work would be confirmed in due course. Some might regard the award for the photoelectric effect ironic, not only because Einstein is far better-known for relativity, but also because the photoelectric effect is a quantum phenomenon, and Einstein became somewhat disenchanted with the path quantum theory would take.