Biography of albert einstein pdf
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He would not join in the widespread support given to the German cause by German intellectuals and did what he could to preserve a rational, international spirit and to urge the immediate end of the war. His feeling of isolation was deepened by the end of his marriage. Mileva Einstein and their two sons spent the war years in Switzerland and the Einsteins were divorced soon after the end of the war.
Einstein then married his cousin Elsa, a widow with two daughters. One of his few consolations was his continued correspondence and occasional visits with his friends in the Netherlands— Paul Ehrenfest and H. Einstein became suddenly famous to the world at large when the deviation of light passing near the sun, as predicted by his general theory of relativity , was observed during the solar eclipse of His name and the term relativity became household words.
He was now able to put the weight of his name behind causes that he believed in, and he did this, always bravely but taking care not to misuse the influence his scientific fame had given him. He also took an active part for a few years in the work of the Committee on Intellectual Cooperation of the League of Nations.
Soon after the end of the war, Einstein and relativity became targets of the anti-Semitic extreme right wing. He was viciously attacked in speeches and articles, and his life was threatened. Despite this treatment Einstein stayed in Berlin, declining many offers to go elsewhere. He did accept an appointment as special professor at Leiden and went there regularly for periods of a week or two to lecture and to discuss current problems in physics.
In Einstein was considering an arrangement that would have allowed him to divide his year between Berlin and the new Institute for Advanced Study at Princeton. But when Hitler came to power in Germany, he promptly resigned his position at the Prussian Academy and joined the Institute. Princeton became his home for the remaining twenty-two years of his life.
He became an American citizen in Roosevelt pointing out the dangerous military potentialities offered by nuclear fission and warning him of the possibility that Germany might be developing these potentialities. This letter helped to initiate the American efforts that eventually produced the nuclear reactor and the fission bomb, but Einstein neither participated in nor knew anything about these efforts.
After the bomb was used and the war had ended, Einstein devoted his energies to the attempt to achieve a world government and to abolish war once and for all. He also spoke out against repression, urging that intellectuals must be prepared to risk everything to preserve freedom of expression. He was drafting a speech on the current tensions between Israel and Egypt when he suffered an attack due to an aortic aneurysm; he died a few days later.
But despite his concern with world problems and his willingness to do whatever he could to alleviate them, his ultimate loyalty was to his science. But our equations are much more important to me, because politics is for the present, but an equation like that is something for eternity. Early Scientific Interests. Albert Einstein started his scientific work at the beginning of the twentieth century.
It was a time of startling experimental discoveries, but the problems that drew his attention and forced him to produce the boldly original ideas of a new physics had developed gradually and involved the very foundations of the subject. The closing decades of the nineteenth century were the period when the long-established goal of physical theory—the explanation of all natural phenomena in terms of mechanics—came under serious scrutiny and was directly challenged.
Mechanical explanation had had great successes, particularly in the theory of heat and in various aspects of optics and electromagnetism; but even the successful mechanical theory of heat had its serious failures and unresolved paradoxes, and physicists had not been able to provide a really satisfactory mechanical foundation for electromagnetic theory.
Many were questioning the whole program of mechanism, and alternatives ranging from the energetics of Wilhelm Ostwald to the electromagnetic world view of Wilhelm Wien were widely considered and vigorously debated. This concern with general principles required something else to make it fruitful, however, and Einstein himself described what it was.
In these articles Einstein rederived by his own methods the basic results of statistical mechanics : the canonical distribution of energy for a system in contact with a heat bath, the equipartition theorem, and the physical interpretations of entropy and temperature. He also emphasized that the probabilities that appear in the theory are to be understood as having a very definite physical meaning.
The probability of a macroscopically identifiable state of a system is the fraction of any sufficiently long time interval that the system spends in this state. Equilibrium is dynamic, with the system passing through all its possible states in an irregular sequence. Ludwig Boltzmann had introduced this point of view years before, but Einstein made it very much his own.
It was in the last of this early series of papers, however, that Einstein introduced a new theme. It appears too in the relation between the entropy S and the probability W of a state. Einstein asked for the physical significance of this constant K. This meant that k defines the scale of fluctuation phenomena or, as Einstein put it, that it determines the thermal stability of a system.
This result shows that fluctuations are normally negligibly small so that the average or thermodynamic value of the energy is a very good measure of this quantity, but Einstein was more interested in its other implications. None of these quantities was known with any precision, and previous determinations involved very indirect theoretical arguments.
No one before Einstein had taken seriously the fluctuation phenomena predicted by statistical mechanics, but he saw that the existence of such fluctuations could be used to demonstrate the correctness of the whole molecular theory of heat. This predicted motion of colloidal particles was already widely known as Brownian motion , but at the time Einstein wrote this paper he knew virtually nothing about what had been observed and hesitated to identify the two motions.
He was not trying to explain an old and puzzling phenomenon, but rather to deduce a result that could be used to test the atomic hypothesis and to determine the basic scale of atomic dimensions. These results helped to convince the remaining skeptics, such as Wilhelm Ostwald , that molecules were real and not just a convenient hypothesis. The theory of Brownian motion was developed further by both Einstein and Maryan von Smoluchowski.
Several years later both men worked on the theory of another fluctuation phenomenon—the opalescence exhibited by a fluid in the immediate neighborhood of its critical point. All the work discussed thus far, significant as it was, does not represent the predominant concern of Albert Einstein throughout his career—the search for a unified foundation for all of physics.
Neither the attempts at a mechanical theory of the electromagnetic field nor the recent efforts to base mechanics on electromagnetism had been successful. This theory strongly influenced Einstein, who often referred to the basic electromagnetic equations as the Maxwell-Lorentz equations. His struggles with these problems led to his most important early work—the special theory of relativity and the theory of quanta.
Quantum Theory and Statistical Mechanics. The heuristic viewpoint of the title was nothing less than the suggestion that light be considered a collection of independent particles of energy, which he called light quanta. Einstein had his reasons for advancing such a bold suggestion, one that seemed to dismiss a century of evidence supporting the wave theory of light.
First among these reasons was a negative result: The combination of the electromagnetic theory of light with the statistical mechanics of particles was incapable of dealing with the problem of black-body radiation. It predicted that radiation in theromodynamic equilibrium within an enclosure would have a frequency distribution corresponding to an infinite amount of energy at the high-frequency end of the spectrum.
This was incompatible with the experimental results, but, worse than that, it meant that the theory did not give an acceptable answer to the problem. Although he was convinced that a new unified fundamental theory was needed for an adequate treatment of the radiation problem, Einstein had no such theory to offer. What he found was that the entropy of black-body radiation in a given frequency interval depends on the volume of the enclosure in the same way that the entropy of a gas depends on its volume.
And because the latter dependence has its origin in the independence of the gas molecules rather than the details of their dynamics, Einstein leaped to the conclusion that the radiation, too, must consist of independent particles of energy. Einstein showed that his strange proposal of light quanta could immediately account for several puzzling properties of fluorescence, photoionization, and especially of the photoelectric effect.
His quantitative prediction of the relationship between the maximum energy of the photoelectrons and the frequency of the incident light was not verified experimentally for a decade. The light quantum hypothesis itself attracted only one or two adherents; it represented too great a departure from accepted ideas. It went far beyond the work Max Planck had done in , in which the energy of certain material oscillators was treated as a discrete variable, capable only of values that were integral multiples of a natural unit proportional to the frequency.
During the years between and it was Einstein who took the lead in probing the significance of the new ideas on quanta. Einstein then realized that if Planck had been right in restricting the energies of his oscillators to integral multiples of hv , in discussing the interaction of molecular oscillators with black-body radiation, then this same restriction should also apply to all oscillations on the molecular scale.
In Einstein pointed out how one could use the quantized energy of the oscillations of atoms in solids to account for departures from the rule of Dulong and Petit. This empirical rule, that the specific heat is the same for one mole of any element in solid form, was understood as a consequence of the theorem of equipartition of energy.
Many light elements, however, had specific heats at room temperature that were much smaller than the Dulong-Petit value. Einstein showed how one could easily calculate the specific heat of a solid all of whose atoms vibrated with the same frequency an assumption he made only as a convenient simplification and obtain a universal curve for the variation of specific heat with temperature.
The only parameter in the theory was the frequency of the quantized vibrations. This specific heat curve approached the Dulong-Petit value at high temperatures; accounted qualitatively for all the departures from the equipartition result, including the absence of electronic contributions to the specific heat; and predicted a new and general law: The specific heats of all solids should approach zero as the absolute temperature approaches zero.
Einstein indicated how the vibration frequencies could be determined from infrared absorption measurements in many cases; several years later he suggested another way of determining these frequencies using their relationship to the elastic constants of the solid. Walther Nernst was planning a program of such measurements to establish his own new heat theorem, later known as the third law of thermodynamics.
Wave-Particle Duality. For Einstein, however, the central problem continued to be the nature of radiation. He had calculated the energy fluctuations of the radiation in a small frequency interval with the help of equation 3 and had found that the fluctuations were the sum of two terms, indicating two apparently independent mechanisms for energy fluctuations.
One term was readily intelligible as due to interfering waves, the other as due to variations in the number of light quanta present in the subvolume under study. Neither a wave nor a particle theory could account for the presence of both terms. Einstein confirmed this result by a completely independent calculation of the Brownian motion that a mirror would have to undergo if it were suspended in an enclosure containing a gas and black-body radiation in thermodynamic equilibrium.
Once again there were wave and particle contributions to the fluctuations in momentum of the suspended mirror. Einstein saw this wave-particle duality in radiation as concrete evidence for his conviction that physics needed a new, unified foundation. His view of the role of light quanta in this new fundamental theory had evolved since he put forward the heuristic suggestion of a corpuscular approach to radiation in Einstein now envisaged a field theory, based on appropriate partial differential equations, probably nonlinear, from which quanta would emerge as singular solutions, along the lines of the electric charges in electrostatics.
To Einstein this suggested that the discreteness of energy and the discreteness of charge might be explained together by the new fundamental theory. There was unfortunately very little to go on in the search for this new theory. It would have to be consistent with the special theory of relativity, but Einstein saw that theory as only a universal formal principle, analogous to the laws of thermodynamics, which gave no clue to the structure of matter or radiation.
His efforts along this line seem to have been comparable in their intensity, although not in their fruitfulness, to his efforts during the following years to create the new gravitational theory—the general theory of relativity. He continued to reflect on the questions surrounding the quantum theory. When Einstein returned to the radiation problem in , the quantum theory had undergone a major change.
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The proof turned on the requirement that absorption and emission of radiation, both spontaneous and stimulated, suffice to keep a gas of atoms in thermodynamic equilibrium. This paper introduced the concept of stimulated emission into the quantum theory and is therefore often described as the basis of laser physics.
Einstein himself considered the most important contribution of this work to be not the new derivation of the distribution law but rather the arguments he presented for the directional character of energy quanta. Although Einstein put particular emphasis on the directionality of light quanta, there was no direct evidence for it until when Arthur Compton explained his experiments on the increase in X-ray wavelength after scattering from free electrons.
Even before this, however, Einstein was trying to devise a crucial experiment to settle the question of the nature of radiation. He held fast to his view that light quanta were indispensable since they described the particle properties really manifested by radiation. Light quanta did not have many other supporters until after the Compton effect, and they were particularly unpopular with Bohr and his co-workers.
Bohr saw no good way of reconciling them with the correspondence principle and was willing to give up the exact validity of the conservation laws in order to avoid quanta. Bose-Einstein Statistics and Wave Mechanics. In Einstein received a paper from a young Indian physicist, S. Bose, setting forth a theory in which radiation was treated as a gas of light quanta.
Einstein was much taken with this extension of his old idea. A gas obeying the Bose-Einstein statistics, as the new counting procedure was later called, showed a variety of interesting properties. De Broglie had no experimental evidence to support his idea and deduced no experimentally testable conclusions from it, so it aroused very little interest.
Einstein, however, was immediately attracted to the idea of matter waves because he saw its relationship to his new theory of the ideal gas. These fluctuations showed the same structure as had the energy fluctuations of black-body radiation; only now it was the particle term that would have been the only one present in the classical gas theory.
He proposed several kinds of experiments which might detect the diffraction of de Broglie waves. When the new matrix mechanics appeared, in the papers of Werner Heisenberg , Max Born , and Pascual Jordan, Einstein was interested but not convinced. Discontent With Quantum Mechanics. In the synthesis that constituted the new quantum mechanics was worked out.
This meant that a full quantum mechanical description of the state of a system would generally specify only probabilities rather than definite values of the dynamical variables of the system. The new theory was intrinsically statistical and renounced as meaningless in principle any attempt to go beyond the probabilities to arrive at a deterministic theory.
Einstein dissented from this majority opinion. He never accepted the finality of the quantum mechanical renunciation of causality or its limitation of physical theory to the unambiguous description of the outcome of fully defined experiments. From the Solvay Congress of , when the quantum mechanical synthesis was first discussed, to the end of his life, Einstein never stopped raising questions about the new physics to which he had contributed so much.
He tried at first to propose conceptual experiments that would prove the logical inconsistency of quantum mechanics, but these arguments were all successfully refuted by Bohr. In Einstein began to stress another objection to quantum mechanics, arguing that its description of physical reality was essentially incomplete, that there were elements of physical reality which did not have counterparts in the theory.
Einstein never abandoned his opposition to the prevailing mode of thought despite the enormous success of quantum mechanics. He never lost his hope that a field theory of the right kind might eventually reach this goal. That Einstein, without whom twentieth-century physics would be unthinkable, should have chosen to follow a separate path was a source of great regret to his colleagues.
But to Einstein himself his choice was inevitable; it was the natural outgrowth of all his years of striving to find a unified foundation for physics. Albert Einstein ranks as one of the most remarkable theoreticians in the history of science.
Bertrand cadart biography of albert einstein
He was also a heartfelt pacifist dedicated to world peace. During a single year, , he produced three papers that are among the most important in twentieth-century physics , and perhaps in all of the recorded history of science, for they revolutionized the way scientists looked at the nature of space , time, and matter. These papers dealt with the nature of particle movement known as Brownian motion , the quantum nature of electromagnetic radiation as demonstrated by the photoelectric effect , and the special theory of relativity.
Although Einstein is probably best known for the last of these works, it was for his quantum explanation of the photoelectric effect that he was awarded the Nobel Prize in physics. In , Einstein extended his special theory of relativity to include certain cases of accelerated motion, resulting in the more general theory of relativity. Both sides of his family had long-established roots in southern Germany, and, at the time of Einstein's birth, his father and uncle Jakob owned a small electrical equipment plant.
When that business failed around , Hermann Einstein moved his family to Munich to make a new beginning. A year after their arrival in Munich, Einstein's only sister, Maja, was born. Although his family was Jewish, Einstein was sent to a Catholic elementary school from to He was then enrolled at the Luitpold Gymnasium in Munich.
During these years, Einstein began to develop some of his earliest interests in science and mathematics, but he gave little outward indication of any special aptitude in these fields. Indeed, he did not begin to talk until the age of three and, by the age of nine, was still not fluent in his native language. In , Hermann Einstein's business failed again, and the family moved once more, this time to Pavia, near Milan, Italy.
Einstein was left behind in Munich to allow him to finish school. Such was not to be the case, however, since he left the gymnasium after only six more months. Einstein's biographer, Philipp Frank, explains that Einstein so thoroughly despised formal schooling that he devised a scheme by which he received a medical excuse from school on the basis of a potential nervous breakdown.
He then convinced a mathematics teacher to certify that he was adequately prepared to begin his college studies without a high school diploma. Other biographies, however, say that Einstein was expelled from the gymnasium on the grounds that he was a disruptive influence at the school. In any case, Einstein then rejoined his family in Italy.
One of his first acts upon reaching Pavia was to give up his German citizenship. He was so unhappy with his native land that he wanted to sever all formal connections with it; in addition, by renouncing his citizenship, he could later return to Germany without being arrested as a draft dodger. As a result, Einstein remained without an official citizenship until he became a Swiss citizen at the age of For most of his first year in Italy, Einstein spent his time traveling, relaxing, and teaching himself calculus and higher mathematics.
When he failed that examination, Einstein enrolled at a Swiss cantonal high school in Aarau. He found the more democratic style of instruction at Aarau much more enjoyable than his experience in Munich and soon began to make rapid progress. He took the entrance examination for the ETH a second time in , passed, and was admitted to the school.
In Einstein , however, Jeremy Bernstein writes that Einstein was admitted without examination on the basis of his diploma from Aarau. He apparently hated studying for examinations and was not especially interested in attending classes on a regular basis. He devoted much of this time to reading on his own, specializing in the works of Gustav Kirchhoff, Heinrich Hertz, James Clerk Maxwell , Ernst Mach , and other classical physicists.
When Einstein graduated with a teaching degree in , he was unable to find a regular teaching job. Instead, he supported himself as a tutor in a private school in Schaffhausen. In , Einstein also published his first scientific paper, "Consequences of Capillary Phenomena. He was given a probationary appointment to begin in June of that year and was promoted to the position of technical expert, third class, a few months later.
The seven years Einstein spent at the Patent Office were the most productive years of his life. The demands of his work were relatively modest and he was able to devote a great deal of time to his own research. The promise of a steady income at the Patent Office also made it possible for Einstein to marry. Mileva Maric also given as Maritsch was a fellow student in physics at ETH, and Einstein had fallen in love with her even though his parents strongly objected to the match.
Maric had originally come from Hungary and was of Serbian and Greek Orthodox heritage. The couple married in , and later had two sons, Hans Albert and Edward. In , Einstein published a series of papers, any one of which would have assured his fame in history. Brown had reported that tiny particles, such as dust particles, move about with a rapid and random zigzag motion when suspended in a liquid.
Einstein hypothesized that the visible motion of particles was caused by the random movement of molecules that make up the liquid. He derived a mathematical formula that predicted the distance traveled by particles and their relative speed. This formula was confirmed experimentally by the French physicist Jean Baptiste Perrin in Einstein's work on the Brownian movement is generally regarded as the first direct experimental evidence of the existence of molecules.
A second paper, "On a Heuristic Viewpoint concerning the Production and Transformation of Light," dealt with another puzzle in physics, the photoelectric effect. First observed by Heinrich Hertz in , the photoelectric effect involves the release of electrons from a metal that occurs when light is shined on the metal. The puzzling aspect of the photo-electric effect was that the number of electrons released is not a function of the light's intensity, but of the color that is, the wavelength of the light.
To solve this problem, Einstein made use of a concept developed only a few years before, in , by the German physicist Max Planck , the quantum hypothesis. Einstein assumed that light travels in tiny discrete bundles, or "quanta," of energy. The energy of any given light quantum later renamed the photon , Einstein said, is a function of its wavelength.
Thus, when light falls on a metal, electrons in the metal absorb specific quanta of energy, giving them enough energy to escape from the surface of the metal. But the number of electrons released will be determined not by the number of quanta that is, the intensity of the light, but by its energy that is, its wavelength. Einstein's hypothesis was confirmed by several experiments and laid the foundation for the fields of quantitative photoelectric chemistry and quantum mechanics.
As recognition for this work, Einstein was awarded the Nobel Prize in physics. A third paper by Einstein, almost certainly the one for which he became best known, details his special theory of relativity. In essence, "On the Electrodynamics of Moving Bodies" discusses the relationship between measurements made by observers in two separate systems moving at constant velocity with respect to each other.
Einstein's work on relativity was by no means the first in the field. Each had developed mathematical formulas that described the effect of motion on various types of measurement. Indeed, the record of pre-Einstein thought on relativity is so extensive that one historian of science once wrote a two-volume work on the subject that devoted only a single sentence to Einstein's work.
Still, there is little question that Einstein provided the most complete analysis of this subject. He began by making two assumptions. First, he said that the laws of physics are the same in all frames of reference. Second, he declared that the velocity of light is always the same, regardless of the conditions under which it is measured. Using only these two assumptions, Einstein proceeded to uncover an unexpectedly extensive description of the properties of bodies that are in uniform motion.
For example, he showed that the length and mass of an object are dependent upon their movement relative to an observer. He derived a mathematical relationship between the length of an object and its velocity that had previously been suggested by both FitzGerald and Lorentz. Einstein's theory was revolutionary, for previously scientists had believed that basic quantities of measurement such as time, mass, and length were absolute and unchanging.
Einstein's work established the opposite — that these measurements could change, depending on the relative motion of the observer. In addition to his masterpieces on the photoelectric effect, Brownian movement, and relativity, Einstein wrote two more papers in He came to the conclusion in this paper that the energy and mass of a body are closely interrelated.
Fame did not come to Einstein immediately as a result of his five papers. Indeed, he submitted his paper on relativity to the University of Bern in support of his application to become a privatdozent , or unsalaried instructor, but the paper and application were rejected. His work was too important to be long ignored, however, and a second application three years later was accepted.
Einstein spent only a year at Bern, however, before taking a job as professor of physics at the University of Zurich in A year later Einstein was made director of scientific research at the Kaiser Wilhelm Institute for Physics in Berlin , a post he held from to Einstein was increasingly occupied with his career and his wife with managing their household; upon moving to Berlin in , the couple grew distant.
The two were never reconciled; in , they were formally divorced. With the outbreak of the war, Einstein's pacifist views became public knowledge. Bertrand Cadart moved to Queensland three years ago to be closer to his family and continue his battle against leukaemia. He passed away on Good Friday. My friend has a full La Parisenne fairing for an XS hanging on his garage wall, its in good order and is well made,must remind him to install it.
Biography of albert einstein summary
Join today! Reading Motorcycling Mayor loses cancer battle. Share Tweet. Motorcycling Mayor loses cancer battle. In the last decade of his life, Einstein, who had always seen himself as a loner, withdrew even further from any sort of spotlight, preferring to stay close to Princeton and immerse himself in processing ideas with colleagues. He corresponded with scholar and activist W.
Einstein was very particular about his sleep schedule, claiming he needed 10 hours of sleep per day to function well. His theory of relativity allegedly came to him in a dream about cows being electrocuted. He was also known to take regular naps. He is said to have held objects like a spoon or pencil in his hand while falling asleep.
That way, he could wake up before hitting the second stage of sleep—a hypnagogic process believed to boost creativity and capture sleep-inspired ideas. Although sleep was important to Einstein, socks were not. He was famous for refusing to wear them. According to a letter he wrote to future wife Elsa, he stopped wearing them because he was annoyed by his big toe pushing through the material and creating a hole.
One of the most recognizable photos of the 20 th century shows Einstein sticking out his tongue while leaving his 72 nd birthday party on March 14, According to Discovery. Tired from doing so all night, he refused and rebelliously stuck his tongue out at the crowd for a moment before turning away. UPI photographer Arthur Sasse captured the shot.
Einstein was amused by the picture and ordered several prints to give to his friends. He was taken to the hospital for treatment but refused surgery, believing that he had lived his life and was content to accept his fate. I have done my share, it is time to go. I will do it elegantly.
He was able to photograph the office just as Einstein left it. However, during his life, Einstein participated in brain studies, and at least one biography claimed he hoped researchers would study his brain after he died. In keeping with his wishes, the rest of his body was cremated and the ashes scattered in a secret location. According to The New York Times , the researchers believe it might help explain why Einstein was so intelligent.
Rorke-Adams said she received the brain slides from Harvey. Einstein has also been portrayed on screen. Walter Matthau portrayed Einstein in the fictional comedy I. A much more historically accurate depiction of Einstein came in , when he was the subject of the first season of Genius , a part scripted miniseries by National Geographic.
Johnny Flynn played a younger version of the scientist, while Geoffrey Rush portrayed Einstein in his later years after he had fled Germany. Ron Howard was the director. Robert Oppenheimer during his involvement with the Manhattan Project. Race is a fraud. All modern people are the conglomeration of so many ethnic mixtures that no pure race remains.
Once in the US, Einstein dedicated himself to a strict discipline of academic study. He would spend no time on maintaining his dress and image. Einstein was notoriously absent-minded. In his youth, he once left his suitcase at a friends house. Although a bit of a loner, and happy in his own company, he had a good sense of humour.
On January 3, , Einstein received a letter from a girl who was having difficulties with mathematics in her studies. Einstein consoled her when he wrote in reply to her letter. I can assure you that mine are still greater. But, he followed no established religion.
Biography of thomas alva edison: Bertrand Cadart, former mayor of Glamorgan Spring Bay and Mad Max actor, sadly passed away on Good Friday this year. He’d been fighting a three-year battle with cancer. Bertrand was born on 30 April in Amiens*, Somme, France.
His view of God sought to establish a harmony between science and religion. Einstein described himself as a Zionist Socialist. He did support the state of Israel but became concerned about the narrow nationalism of the new state. In , he was offered the position as President of Israel, but he declined saying he had:. Albert Einstein was involved in many civil rights movements such as the American campaign to end lynching.
But he also spoke highly of the meritocracy in American society and the value of being able to speak freely. On the outbreak of war in , Einstein wrote to President Roosevelt about the prospect of Germany developing an atomic bomb. He warned Roosevelt that the Germans were working on a bomb with a devastating potential.
Roosevelt headed his advice and started the Manhattan project to develop the US atom bomb. But, after the war ended, Einstein reverted to his pacifist views. Einstein said after the war. In the post-war McCarthyite era, Einstein was scrutinised closely for potential Communist links. He was also a strong critic of the arms race. Einstein remarked:.
Einstein was feted as a scientist, but he was a polymath with interests in many fields.