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135-538: Albert Einstein ( / ˈ aɪ n s t aɪ n / , EYEN -styne ; German: [ˈalbɛʁt ˈʔaɪnʃtaɪn] ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who is widely held as one of the most influential scientists . Best known for developing the theory of relativity , Einstein also made important contributions to quantum mechanics . His mass–energy equivalence formula E = mc , which arises from special relativity , has been called "the world's most famous equation". He received

270-429: A Hitler Youth camp. In April 1933, Einstein discovered that the new German government had passed laws barring Jews from holding any official positions , including teaching at universities. Historian Gerald Holton describes how, with "virtually no audible protest being raised by their colleagues", thousands of Jewish scientists were suddenly forced to give up their university positions and their names were removed from

405-435: A mathematical theory , in the sense that the word "theory" has a different meaning in mathematical terms. R i c = k g {\displaystyle \mathrm {Ric} =kg} The equations for an Einstein manifold , used in general relativity to describe the curvature of spacetime A physical theory involves one or more relationships between various measurable quantities. Archimedes realized that

540-572: A unified field theory by generalizing his geometric theory of gravitation to include electromagnetism . As a result, he became increasingly isolated from the mainstream modern physics . His intellectual achievements and originality made Einstein broadly synonymous with genius . In 1999, he was named Time 's Person of the Century . Albert Einstein was born in Ulm , in the Kingdom of Württemberg in

675-658: A working hypothesis . Electromagnetism In physics, electromagnetism is an interaction that occurs between particles with electric charge via electromagnetic fields . The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interactions of atoms and molecules . Electromagnetism can be thought of as a combination of electrostatics and magnetism , which are distinct but closely intertwined phenomena. Electromagnetic forces occur between any two charged particles. Electric forces cause an attraction between particles with opposite charges and repulsion between particles with

810-766: A "citizen of the world" who should be offered a temporary shelter in the UK. Both bills failed, however, and Einstein then accepted an earlier offer from the Institute for Advanced Study , in Princeton, New Jersey , US, to become a resident scholar. Theoretical physicist The advancement of science generally depends on the interplay between experimental studies and theory . In some cases, theoretical physics adheres to standards of mathematical rigour while giving little weight to experiments and observations. For example, while developing special relativity , Albert Einstein

945-539: A banner headline that read: "Revolution in Science ;– New Theory of the Universe ;– Newtonian Ideas Overthrown". With Eddington's eclipse observations widely reported not just in academic journals but by the popular press as well, Einstein became "perhaps the world's first celebrity scientist", a genius who had shattered a paradigm that had been basic to physicists' understanding of the universe since

1080-519: A bill to parliament to extend British citizenship to Einstein, during which period Einstein made a number of public appearances describing the crisis brewing in Europe. In one of his speeches he denounced Germany's treatment of Jews, while at the same time he introduced a bill promoting Jewish citizenship in Palestine, as they were being denied citizenship elsewhere. In his speech he described Einstein as

1215-404: A certain economy and elegance (compare to mathematical beauty ), a notion sometimes called " Occam's razor " after the 13th-century English philosopher William of Occam (or Ockham), in which the simpler of two theories that describe the same matter just as adequately is preferred (but conceptual simplicity may mean mathematical complexity). They are also more likely to be accepted if they connect

1350-724: A chair at the German Charles-Ferdinand University in Prague, a move which required him to become an Austrian citizen of the Austro-Hungarian Empire . His time in Prague saw him producing eleven research papers. In July 1912, he returned to his alma mater , the ETH Zurich , to take up a chair in theoretical physics. His teaching activities there centred on thermodynamics and analytical mechanics, and his research interests included

1485-574: A civil servant approached its end in 1908, when he secured a junior teaching position at the University of Bern . In 1909, a lecture on relativistic electrodynamics that he gave at the University of Zurich, much admired by Alfred Kleiner, led to Zürich's luring him away from Bern with a newly created associate professorship. Promotion to a full professorship followed in April 1911, when he accepted

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1620-738: A contract to install electric lighting in Munich, but without success—they lacked the capital that would have been required to update their technology from direct current to the more efficient, alternating current alternative. The failure of their bid forced them to sell their Munich factory and search for new opportunities elsewhere. The Einstein family moved to Italy, first to Milan and a few months later to Pavia , where they settled in Palazzo Cornazzani . Einstein, then fifteen, stayed behind in Munich in order to finish his schooling. His father wanted him to study electrical engineering , but he

1755-676: A diploma handed to him by King Alfonso XIII . (His Spanish trip also gave him a chance to meet a fellow Nobel laureate, the neuroanatomist Santiago Ramón y Cajal .) From 1922 until 1932, with the exception of a few months in 1923 and 1924, Einstein was a member of the Geneva-based International Committee on Intellectual Cooperation of the League of Nations , a group set up by the League to encourage scientists, artists, scholars, teachers and other people engaged in

1890-414: A force law for the interaction between elements of electric current, Ampère placed the subject on a solid mathematical foundation. A theory of electromagnetism, known as classical electromagnetism , was developed by several physicists during the period between 1820 and 1873, when James Clerk Maxwell 's treatise was published, which unified previous developments into a single theory, proposing that light

2025-500: A form of protoscience and others are a form of pseudoscience . The falsification of the original theory sometimes leads to reformulation of the theory. "Thought" experiments are situations created in one's mind, asking a question akin to "suppose you are in this situation, assuming such is true, what would follow?". They are usually created to investigate phenomena that are not readily experienced in every-day situations. Famous examples of such thought experiments are Schrödinger's cat ,

2160-578: A formative event from his youth, when he was sick in bed and his father brought him a compass . This sparked his lifelong fascination with electromagnetism . He realized that "Something deeply hidden had to be behind things." Albert attended St. Peter's Catholic elementary school in Munich from the age of five. When he was eight, he was transferred to the Luitpold Gymnasium , where he received advanced primary and then secondary school education. In 1894, Hermann and Jakob's company tendered for

2295-766: A good example. For instance: " phenomenologists " might employ ( semi- ) empirical formulas and heuristics to agree with experimental results, often without deep physical understanding . "Modelers" (also called "model-builders") often appear much like phenomenologists, but try to model speculative theories that have certain desirable features (rather than on experimental data), or apply the techniques of mathematical modeling to physics problems. Some attempt to create approximate theories, called effective theories , because fully developed theories may be regarded as unsolvable or too complicated . Other theorists may try to unify , formalise, reinterpret or generalise extant theories, or create completely new ones altogether. Sometimes

2430-461: A gravel sorter and an electric typewriter. His employers were pleased enough with his work to make his position permanent in 1903, although they did not think that he should be promoted until he had "fully mastered machine technology". It is conceivable that his labors at the patent office had a bearing on his development of his special theory of relativity. He arrived at his revolutionary ideas about space, time and light through thought experiments about

2565-452: A gravitational field would be unable to find any evidence that the field exists. In 1911, he used the principle to estimate the amount by which a ray of light from a distant star would be bent by the gravitational pull of the Sun as it passed close to the Sun's photosphere (that is, the Sun's apparent surface). He reworked his calculation in 1913, having now found a way to model gravitation with

2700-533: A host of prominent German thinkers that justified Germany's belligerence—Einstein was one of the few German intellectuals to distance himself from it and sign the alternative, eirenic " Manifesto to the Europeans " instead. However, this expression of his doubts about German policy did not prevent him from being elected to a two-year term as president of the German Physical Society in 1916. When

2835-648: A house in De Haan, Belgium, where he lived for a few months. In late July 1933, he visited England for about six weeks at the invitation of the British Member of Parliament Commander Oliver Locker-Lampson , who had become friends with him in the preceding years. Locker-Lampson invited him to stay near his Cromer home in a secluded wooden cabin on Roughton Heath in the Parish of Roughton, Norfolk . To protect Einstein, Locker-Lampson had two bodyguards watch over him;

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2970-436: A link between human-made electric current and magnetism was Gian Romagnosi , who in 1802 noticed that connecting a wire across a voltaic pile deflected a nearby compass needle. However, the effect did not become widely known until 1820, when Ørsted performed a similar experiment. Ørsted's work influenced Ampère to conduct further experiments, which eventually gave rise to a new area of physics: electrodynamics. By determining

3105-474: A magnetic field transforms to a field with a nonzero electric component and conversely, a moving electric field transforms to a nonzero magnetic component, thus firmly showing that the phenomena are two sides of the same coin. Hence the term "electromagnetism". (For more information, see Classical electromagnetism and special relativity and Covariant formulation of classical electromagnetism .) Today few problems in electromagnetism remain unsolved. These include:

3240-446: A magnetic needle using a Voltaic pile. The factual setup of the experiment is not completely clear, nor if current flowed across the needle or not. An account of the discovery was published in 1802 in an Italian newspaper, but it was largely overlooked by the contemporary scientific community, because Romagnosi seemingly did not belong to this community. An earlier (1735), and often neglected, connection between electricity and magnetism

3375-454: A man can be." In 1912, Einstein entered into a relationship with Elsa Löwenthal , who was both his first cousin on his mother's side and his second cousin on his father's. When Marić learned of his infidelity soon after moving to Berlin with him in April 1914, she returned to Zürich, taking Hans Albert and Eduard with her. Einstein and Marić were granted a divorce on 14 February 1919 on the grounds of having lived apart for five years. As part of

3510-452: A nearby compass needle to move. At the time of discovery, Ørsted did not suggest any satisfactory explanation of the phenomenon, nor did he try to represent the phenomenon in a mathematical framework. However, three months later he began more intensive investigations. Soon thereafter he published his findings, proving that an electric current produces a magnetic field as it flows through a wire. The CGS unit of magnetic induction ( oersted )

3645-498: A new branch of mathematics: infinite, orthogonal series . Modern theoretical physics attempts to unify theories and explain phenomena in further attempts to understand the Universe , from the cosmological to the elementary particle scale. Where experimentation cannot be done, theoretical physics still tries to advance through the use of mathematical models. Mainstream theories (sometimes referred to as central theories ) are

3780-445: A paper which laid the foundations for the concepts of both laser and maser , and contained a trove of information that would be beneficial to developments in physics later on. In the middle part of his career, Einstein made important contributions to statistical mechanics and quantum theory. Especially notable was his work on the quantum physics of radiation , in which light consists of particles, subsequently called photons . With

3915-739: A photo of them carrying shotguns and guarding Einstein was published in the Daily Herald on 24 July 1933. Locker-Lampson took Einstein to meet Winston Churchill at his home, and later, Austen Chamberlain and former Prime Minister Lloyd George . Einstein asked them to help bring Jewish scientists out of Germany. British historian Martin Gilbert notes that Churchill responded immediately, and sent his friend, physicist Frederick Lindemann , to Germany to seek out Jewish scientists and place them in British universities. Churchill later observed that as

4050-660: A platform from which to promote traditional Catholic doctrine. Einstein's former physics professor Hendrik Lorentz and the Polish chemist Marie Curie were also members of the committee. In March and April 1925, Einstein and his wife visited South America, where they spent about a week in Brazil, a week in Uruguay and a month in Argentina. Their tour was suggested by Jorge Duclout (1856–1927) and Mauricio Nirenstein (1877–1935) with

4185-646: A result of Germany having driven the Jews out, they had lowered their "technical standards" and put the Allies ' technology ahead of theirs. Einstein later contacted leaders of other nations, including Turkey's Prime Minister, İsmet İnönü , to whom he wrote in September 1933, requesting placement of unemployed German-Jewish scientists. As a result of Einstein's letter, Jewish invitees to Turkey eventually totaled over "1,000 saved individuals". Locker-Lampson also submitted

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4320-492: A role in chemical reactivity; such relationships are studied in spin chemistry . Electromagnetism also plays several crucial roles in modern technology : electrical energy production, transformation and distribution; light, heat, and sound production and detection; fiber optic and wireless communication; sensors; computation; electrolysis; electroplating; and mechanical motors and actuators. Electromagnetism has been studied since ancient times. Many ancient civilizations, including

4455-413: A sewing-needle by means of the discharge of Leyden jars." The electromagnetic force is the second strongest of the four known fundamental forces and has unlimited range. All other forces, known as non-fundamental forces . (e.g., friction , contact forces) are derived from the four fundamental forces. At high energy, the weak force and electromagnetic force are unified as a single interaction called

4590-498: A ship floats by displacing its mass of water, Pythagoras understood the relation between the length of a vibrating string and the musical tone it produces. Other examples include entropy as a measure of the uncertainty regarding the positions and motions of unseen particles and the quantum mechanical idea that ( action and) energy are not continuously variable. Theoretical physics consists of several different approaches. In this regard, theoretical particle physics forms

4725-401: A short time after he had given the twelve year old Einstein a geometry textbook, the boy "had worked through the whole book. He thereupon devoted himself to higher mathematics ... Soon the flight of his mathematical genius was so high I could not follow." Einstein recorded that he had "mastered integral and differential calculus " while still just fourteen. His love of algebra and geometry

4860-462: A subsequent letter to physicist and friend Max Born , who had already emigrated from Germany to England, Einstein wrote, "... I must confess that the degree of their brutality and cowardice came as something of a surprise." After moving to the US, he described the book burnings as a "spontaneous emotional outburst" by those who "shun popular enlightenment", and "more than anything else in the world, fear

4995-600: A tour of his studio and introduced him to Chaplin. They had an instant rapport, with Chaplin inviting Einstein and his wife, Elsa, to his home for dinner. Chaplin said Einstein's outward persona, calm and gentle, seemed to conceal a "highly emotional temperament", from which came his "extraordinary intellectual energy". Chaplin's film City Lights was to premiere a few days later in Hollywood, and Chaplin invited Einstein and Elsa to join him as his special guests. Walter Isaacson , Einstein's biographer, described this as "one of

5130-477: A twenty year old Serbian , Mileva Marić . Over the next few years, the pair spent many hours discussing their shared interests and learning about topics in physics that the polytechnic school's lectures did not cover. In his letters to Marić, Einstein confessed that exploring science with her by his side was much more enjoyable than reading a textbook in solitude. Eventually the two students became not only friends but also lovers. Historians of physics are divided on

5265-508: A unified concept of energy. This unification, which was observed by Michael Faraday , extended by James Clerk Maxwell , and partially reformulated by Oliver Heaviside and Heinrich Hertz , is one of the key accomplishments of 19th-century mathematical physics . It has had far-reaching consequences, one of which was the understanding of the nature of light . Unlike what was proposed by the electromagnetic theory of that time, light and other electromagnetic waves are at present seen as taking

5400-510: A visitor is the joyous, positive attitude to life ... The American is friendly, self-confident, optimistic, and without envy." In 1922, Einstein's travels were to the old world rather than the new. He devoted six months to a tour of Asia that saw him speaking in Japan, Singapore and Sri Lanka (then known as Ceylon ). After his first public lecture in Tokyo, he met Emperor Yoshihito and his wife at

5535-469: A wide range of phenomena. Testing the consequences of a theory is part of the scientific method . Physical theories can be grouped into three categories: mainstream theories , proposed theories and fringe theories . Theoretical physics began at least 2,300 years ago, under the Pre-socratic philosophy , and continued by Plato and Aristotle , whose views held sway for a millennium. During

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5670-497: Is a model of physical events. It is judged by the extent to which its predictions agree with empirical observations. The quality of a physical theory is also judged on its ability to make new predictions which can be verified by new observations. A physical theory differs from a mathematical theorem in that while both are based on some form of axioms , judgment of mathematical applicability is not based on agreement with any experimental results. A physical theory similarly differs from

5805-411: Is compatible with special relativity. According to Maxwell's equations, the speed of light in vacuum is a universal constant that is dependent only on the electrical permittivity and magnetic permeability of free space . This violates Galilean invariance , a long-standing cornerstone of classical mechanics. One way to reconcile the two theories (electromagnetism and classical mechanics) is to assume

5940-400: Is named in honor of his contributions to the field of electromagnetism. His findings resulted in intensive research throughout the scientific community in electrodynamics. They influenced French physicist André-Marie Ampère 's developments of a single mathematical form to represent the magnetic forces between current-carrying conductors. Ørsted's discovery also represented a major step toward

6075-508: Is no one-to-one correspondence between electromagnetic units in SI and those in CGS, as is the case for mechanical units. Furthermore, within CGS, there are several plausible choices of electromagnetic units, leading to different unit "sub-systems", including Gaussian , "ESU", "EMU", and Heaviside–Lorentz . Among these choices, Gaussian units are the most common today, and in fact the phrase "CGS units"

6210-454: Is studied, for example, in the subject of magnetohydrodynamics , which combines Maxwell theory with the Navier–Stokes equations . Another branch of electromagnetism dealing with nonlinearity is nonlinear optics . Here is a list of common units related to electromagnetism: In the electromagnetic CGS system, electric current is a fundamental quantity defined via Ampère's law and takes

6345-539: The EPR thought experiment , simple illustrations of time dilation , and so on. These usually lead to real experiments designed to verify that the conclusion (and therefore the assumptions) of the thought experiments are correct. The EPR thought experiment led to the Bell inequalities , which were then tested to various degrees of rigor , leading to the acceptance of the current formulation of quantum mechanics and probabilism as

6480-595: The Greeks and the Mayans , created wide-ranging theories to explain lightning , static electricity , and the attraction between magnetized pieces of iron ore . However, it was not until the late 18th century that scientists began to develop a mathematical basis for understanding the nature of electromagnetic interactions. In the 18th and 19th centuries, prominent scientists and mathematicians such as Coulomb , Gauss and Faraday developed namesake laws which helped to explain

6615-626: The Imperial Palace , with thousands of spectators thronging the streets in the hope of catching a glimpse of him. (In a letter to his sons, he wrote that Japanese people seemed to him to be generally modest, intelligent and considerate, and to have a true appreciation of art. But his picture of them in his diary was less flattering: "[the] intellectual needs of this nation seem to be weaker than their artistic ones – natural disposition?" His journal also contains views of China and India which were uncomplimentary. Of Chinese people, he wrote that "even

6750-825: The Prussian Academy of Sciences and the Humboldt University of Berlin , becoming director of the Kaiser Wilhelm Institute for Physics in 1917. In 1933, while Einstein was visiting the United States, Adolf Hitler came to power in Germany. Horrified by the Nazi persecution of his fellow Jews, Einstein decided to remain in the US. On the eve of World War II , he endorsed a letter to President Franklin D. Roosevelt alerting him to

6885-426: The Prussian Academy of Sciences , the directorship of the planned Kaiser Wilhelm Institute for Physics and a chair at the Humboldt University of Berlin that would allow him to pursue his research supported by a professorial salary but with no teaching duties to burden him. Their invitation was all the more appealing to him because Berlin happened to be the home of his latest girlfriend, Elsa Löwenthal. He duly joined

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7020-566: The Riemann curvature tensor of a non-Euclidean four-dimensional spacetime . By the fall of 1915, his reimagining of the mathematics of gravitation in terms of Riemannian geometry was complete, and he applied his new theory not just to the behavior of the Sun as a gravitational lens but also to another astronomical phenomenon, the precession of the perihelion of Mercury (a slow drift in the point in Mercury's elliptical orbit at which it approaches

7155-572: The Scientific Revolution gathered pace, the concepts of matter , energy, space, time and causality slowly began to acquire the form we know today, and other sciences spun off from the rubric of natural philosophy . Thus began the modern era of theory with the Copernican paradigm shift in astronomy, soon followed by Johannes Kepler 's expressions for planetary orbits, which summarized the meticulous observations of Tycho Brahe ;

7290-424: The chemical and physical phenomena observed in daily life. The electrostatic attraction between atomic nuclei and their electrons holds atoms together. Electric forces also allow different atoms to combine into molecules, including the macromolecules such as proteins that form the basis of life . Meanwhile, magnetic interactions between the spin and angular momentum magnetic moments of electrons also play

7425-564: The electroweak interaction . Most of the forces involved in interactions between atoms are explained by electromagnetic forces between electrically charged atomic nuclei and electrons . The electromagnetic force is also involved in all forms of chemical phenomena . Electromagnetism explains how materials carry momentum despite being composed of individual particles and empty space. The forces we experience when "pushing" or "pulling" ordinary material objects result from intermolecular forces between individual molecules in our bodies and in

7560-408: The permeability as a dimensionless quantity (relative permeability) whose value in vacuum is unity . As a consequence, the square of the speed of light appears explicitly in some of the equations interrelating quantities in this system. Formulas for physical laws of electromagnetism (such as Maxwell's equations ) need to be adjusted depending on what system of units one uses. This is because there

7695-599: The quantized nature of matter. In QED, changes in the electromagnetic field are expressed in terms of discrete excitations, particles known as photons , the quanta of light. Investigation into electromagnetic phenomena began about 5,000 years ago. There is evidence that the ancient Chinese , Mayan , and potentially even Egyptian civilizations knew that the naturally magnetic mineral magnetite had attractive properties, and many incorporated it into their art and architecture. Ancient people were also aware of lightning and static electricity , although they had no idea of

7830-461: The two-fluid theory of electricity are two cases in this point. However, an exception to all the above is the wave–particle duality , a theory combining aspects of different, opposing models via the Bohr complementarity principle . Physical theories become accepted if they are able to make correct predictions and no (or few) incorrect ones. The theory should have, at least as a secondary objective,

7965-674: The 1921 Nobel Prize in Physics . Born in the German Empire , Einstein moved to Switzerland in 1895, and at the age of seventeen he enrolled in the mathematics and physics teaching diploma program at the Swiss federal polytechnic school . In 1903, he secured a permanent position at the Swiss Patent Office . In 1905, he submitted a successful PhD dissertation to the University of Zurich . In 1914, he moved to Berlin to join

8100-429: The 19th century. Another important event in the 19th century was the discovery of electromagnetic theory , unifying the previously separate phenomena of electricity, magnetism and light. The pillars of modern physics , and perhaps the most revolutionary theories in the history of physics, have been relativity theory and quantum mechanics . Newtonian mechanics was subsumed under special relativity and Newton's gravity

8235-753: The Academy on 24 July 1913, and moved into an apartment in the Berlin district of Dahlem on 1 April 1914. He was installed in his Humboldt University position shortly thereafter. The outbreak of the First World War in July 1914 marked the beginning of Einstein's gradual estrangement from the nation of his birth. When the " Manifesto of the Ninety-Three " was published in October 1914—a document signed by

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8370-484: The British High Commissioner, welcomed him with a degree of ceremony normally only accorded to a visiting head of state, including a cannon salute. One reception held in his honor was stormed by people determined to hear him speak: he told them that he was happy that Jews were beginning to be recognized as a force in the world. Einstein's decision to tour the eastern hemisphere in 1922 meant that he

8505-476: The Dutchmen Snell and Huygens. In the 18th and 19th centuries Joseph-Louis Lagrange , Leonhard Euler and William Rowan Hamilton would extend the theory of classical mechanics considerably. They picked up the interactive intertwining of mathematics and physics begun two millennia earlier by Pythagoras. Among the great conceptual achievements of the 19th and 20th centuries were the consolidation of

8640-587: The Earth ) or may be an alternative model that provides answers that are more accurate or that can be more widely applied. In the latter case, a correspondence principle will be required to recover the previously known result . Sometimes though, advances may proceed along different paths. For example, an essentially correct theory may need some conceptual or factual revisions; atomic theory , first postulated millennia ago (by several thinkers in Greece and India ) and

8775-484: The German Empire, on 14 March 1879. His parents, secular Ashkenazi Jews , were Hermann Einstein , a salesman and engineer, and Pauline Koch . In 1880, the family moved to Munich 's borough of Ludwigsvorstadt-Isarvorstadt , where Einstein's father and his uncle Jakob founded Elektrotechnische Fabrik J. Einstein & Cie, a company that manufactured electrical equipment based on direct current . He often related

8910-822: The German Reichstag had passed the Enabling Act on 23 March, transforming Hitler's government into a de facto legal dictatorship, and that they would not be able to proceed to Berlin. Later on, they heard that their cottage had been raided by the Nazis and Einstein's personal sailboat confiscated. Upon landing in Antwerp , Belgium on 28 March, Einstein immediately went to the German consulate and surrendered his passport, formally renouncing his German citizenship. The Nazis later sold his boat and converted his cottage into

9045-463: The Indian physicist Satyendra Nath Bose , he laid the groundwork for Bose-Einstein statistics . For much of the last phase of his academic life, Einstein worked on two endeavors that proved ultimately unsuccessful. First, he advocated against quantum theory's introduction of fundamental randomness into science's picture of the world, objecting that "God does not play dice". Second, he attempted to devise

9180-720: The Investigation of the State of the Ether in a Magnetic Field". Einstein excelled at physics and mathematics from an early age, and soon acquired the mathematical expertise normally only found in a child several years his senior. He began teaching himself algebra, calculus and Euclidean geometry when he was twelve; he made such rapid progress that he discovered an original proof of the Pythagorean theorem before his thirteenth birthday. A family tutor, Max Talmud , said that only

9315-713: The Kaiser Wilhelm Institute for Physics opened its doors the following year—its foundation delayed because of the war—Einstein was appointed its first director, just as Planck and Nernst had promised. Einstein was elected a Foreign Member of the Royal Netherlands Academy of Arts and Sciences in 1920, and a Foreign Member of the Royal Society in 1921 . In 1922, he was awarded the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of

9450-434: The Sun most closely). A total eclipse of the Sun that took place on 29 May 1919 provided an opportunity to put his theory of gravitational lensing to the test, and observations performed by Sir Arthur Eddington yielded results that were consistent with his calculations. Eddington's work was reported at length in newspapers around the world. On 7 November 1919, for example, the leading British newspaper, The Times , printed

9585-546: The Swiss authorities deemed him medically unfit for military service. He found that Swiss schools too appeared to have no use for him, failing to offer him a teaching position despite the almost two years that he spent applying for one. Eventually it was with the help of Marcel Grossmann 's father that he secured a post in Bern at the Swiss Patent Office , as an assistant examiner – level III . Patent applications that landed on Einstein's desk for his evaluation included ideas for

9720-541: The United States, drawn back to the US by the offer of a two month research fellowship at the California Institute of Technology . Caltech supported him in his wish that he should not be exposed to quite as much attention from the media as he had experienced when visiting the US in 1921, and he therefore declined all the invitations to receive prizes or make speeches that his admirers poured down upon him. But he remained willing to allow his fans at least some of

9855-458: The ability to disturb a compass needle. The link between lightning and electricity was not confirmed until Benjamin Franklin 's proposed experiments in 1752 were conducted on 10   May 1752 by Thomas-François Dalibard of France using a 40-foot-tall (12 m) iron rod instead of a kite and he successfully extracted electrical sparks from a cloud. One of the first to discover and publish

9990-817: The age of sixteen, Einstein sat the entrance examination for the federal polytechnic school (later the Eidgenössische Technische Hochschule, ETH) in Zürich, Switzerland. He failed to reach the required standard in the general part of the test, but performed with distinction in physics and mathematics. On the advice of the polytechnic's principal, he completed his secondary education at the Argovian cantonal school (a gymnasium ) in Aarau , Switzerland, graduating in 1896. While lodging in Aarau with

10125-419: The applications of relativity to problems in astronomy and cosmology respectively . All of these achievements depended on the theoretical physics as a moving force both to suggest experiments and to consolidate results — often by ingenious application of existing mathematics, or, as in the case of Descartes and Newton (with Leibniz ), by inventing new mathematics. Fourier's studies of heat conduction led to

10260-514: The body of knowledge of both factual and scientific views and possess a usual scientific quality of the tests of repeatability, consistency with existing well-established science and experimentation. There do exist mainstream theories that are generally accepted theories based solely upon their effects explaining a wide variety of data, although the detection, explanation, and possible composition are subjects of debate. The proposed theories of physics are usually relatively new theories which deal with

10395-566: The care of his mother or in temporary confinement in an asylum. After her death, he was committed permanently to Burghölzli , the Psychiatric University Hospital in Zürich. Einstein graduated from the federal polytechnic school in 1900, duly certified as competent to teach mathematics and physics. His successful acquisition of Swiss citizenship in February 1901 was not followed by the usual sequel of conscription ;

10530-556: The children are spiritless and look obtuse... It would be a pity if these Chinese supplant all other races. For the likes of us the mere thought is unspeakably dreary".) He was greeted with even greater enthusiasm on the last leg of his tour, in which he spent twelve days in Mandatory Palestine , newly entrusted to British rule by the League of Nations in the aftermath of the First World War. Sir Herbert Samuel ,

10665-509: The completion of the general theory of relativity, proving the Einstein–de Haas effect , contributing to the quantum theory of radiation, and the development of Bose–Einstein statistics . In 1907, Einstein reached a milestone on his long journey from his special theory of relativity to a new idea of gravitation with the formulation of his equivalence principle , which asserts that an observer in an infinitesimally small box falling freely in

10800-494: The curriculum, allotting him a top grade of 6 for history, physics, algebra, geometry, and descriptive geometry. At seventeen, he enrolled in the four-year mathematics and physics teaching diploma program at the federal polytechnic school. Marie Winteler, a year older than him, took up a teaching post in Olsberg , Switzerland. The five other polytechnic school freshmen following the same course as Einstein included just one woman,

10935-502: The deep connections between electricity and magnetism that would be discovered over 2,000 years later. Despite all this investigation, ancient civilizations had no understanding of the mathematical basis of electromagnetism, and often analyzed its impacts through the lens of religion rather than science (lightning, for instance, was considered to be a creation of the gods in many cultures). Electricity and magnetism were originally considered to be two separate forces. This view changed with

11070-438: The divorce settlement, Einstein agreed that if he were to win a Nobel Prize, he would give the money that he received to Marić; he won the prize two years later. Einstein married Löwenthal in 1919. In 1923, he began a relationship with a secretary named Betty Neumann, the niece of his close friend Hans Mühsam. Löwenthal nevertheless remained loyal to him, accompanying him when he emigrated to the United States in 1933. In 1935, she

11205-562: The effects of modern physics , including quantum mechanics and relativity . The theoretical implications of electromagnetism, particularly the requirement that observations remain consistent when viewed from various moving frames of reference ( relativistic electromagnetism ) and the establishment of the speed of light based on properties of the medium of propagation ( permeability and permittivity ), helped inspire Einstein's theory of special relativity in 1905. Quantum electrodynamics (QED) modifies Maxwell's equations to be consistent with

11340-576: The existence of a luminiferous aether through which the light propagates. However, subsequent experimental efforts failed to detect the presence of the aether. After important contributions of Hendrik Lorentz and Henri Poincaré , in 1905, Albert Einstein solved the problem with the introduction of special relativity, which replaced classical kinematics with a new theory of kinematics compatible with classical electromagnetism. (For more information, see History of special relativity .) In addition, relativity theory implies that in moving frames of reference,

11475-435: The existence of self-sustaining electromagnetic waves . Maxwell postulated that such waves make up visible light , which was later shown to be true. Gamma-rays, x-rays, ultraviolet, visible, infrared radiation, microwaves and radio waves were all determined to be electromagnetic radiation differing only in their range of frequencies. In the modern era, scientists continue to refine the theory of electromagnetism to account for

11610-555: The family of Jost Winteler , he fell in love with Winteler's daughter, Marie. (His sister, Maja , later married Winteler's son Paul.) In January 1896, with his father's approval, Einstein renounced his citizenship of the German Kingdom of Württemberg in order to avoid conscription into military service . The Matura (graduation for the successful completion of higher secondary schooling), awarded to him in September 1896, acknowledged him to have performed well across most of

11745-516: The form of quantized , self-propagating oscillatory electromagnetic field disturbances called photons . Different frequencies of oscillation give rise to the different forms of electromagnetic radiation , from radio waves at the lowest frequencies, to visible light at intermediate frequencies, to gamma rays at the highest frequencies. Ørsted was not the only person to examine the relationship between electricity and magnetism. In 1802, Gian Domenico Romagnosi , an Italian legal scholar, deflected

11880-435: The formation and interaction of electromagnetic fields. This process culminated in the 1860s with the discovery of Maxwell's equations , a set of four partial differential equations which provide a complete description of classical electromagnetic fields. Maxwell's equations provided a sound mathematical basis for the relationships between electricity and magnetism that scientists had been exploring for centuries, and predicted

12015-416: The highest order, writing Principia Mathematica . In it contained a grand synthesis of the work of Copernicus, Galileo and Kepler; as well as Newton's theories of mechanics and gravitation, which held sway as worldviews until the early 20th century. Simultaneously, progress was also made in optics (in particular colour theory and the ancient science of geometrical optics ), courtesy of Newton, Descartes and

12150-455: The idea of energy (as well as its global conservation) by the inclusion of heat , electricity and magnetism , and then light . The laws of thermodynamics , and most importantly the introduction of the singular concept of entropy began to provide a macroscopic explanation for the properties of matter. Statistical mechanics (followed by statistical physics and Quantum statistical mechanics ) emerged as an offshoot of thermodynamics late in

12285-501: The influence of men of intellectual independence". Einstein was now without a permanent home, unsure where he would live and work, and equally worried about the fate of countless other scientists still in Germany. Aided by the Academic Assistance Council , founded in April 1933 by British Liberal politician William Beveridge to help academics escape Nazi persecution, Einstein was able to leave Germany. He rented

12420-435: The knives took up the nails. On this the whole number was tried, and found to do the same, and that, to such a degree as to take up large nails, packing needles, and other iron things of considerable weight ... E. T. Whittaker suggested in 1910 that this particular event was responsible for lightning to be "credited with the power of magnetizing steel; and it was doubtless this which led Franklin in 1751 to attempt to magnetize

12555-478: The lack of magnetic monopoles , Abraham–Minkowski controversy , the location in space of the electromagnetic field energy, and the mechanism by which some organisms can sense electric and magnetic fields. The Maxwell equations are linear, in that a change in the sources (the charges and currents) results in a proportional change of the fields. Nonlinear dynamics can occur when electromagnetic fields couple to matter that follows nonlinear dynamical laws. This

12690-675: The late 1920s. In the aftermath of World War 2, more progress brought much renewed interest in QFT, which had since the early efforts, stagnated. The same period also saw fresh attacks on the problems of superconductivity and phase transitions, as well as the first applications of QFT in the area of theoretical condensed matter. The 1960s and 70s saw the formulation of the Standard model of particle physics using QFT and progress in condensed matter physics (theoretical foundations of superconductivity and critical phenomena , among others ), in parallel to

12825-554: The law of the photoelectric effect". At this point some physicists still regarded the general theory of relativity skeptically, and the Nobel citation displayed a degree of doubt even about the work on photoelectricity that it acknowledged: it did not assent to Einstein's notion of the particulate nature of light, which only won over the entire scientific community when S. N. Bose derived the Planck spectrum in 1924. That same year, Einstein

12960-479: The life of the mind to work more closely with their counterparts in other countries. He was appointed as a German delegate rather than as a representative of Switzerland because of the machinations of two Catholic activists, Oskar Halecki and Giuseppe Motta . By persuading Secretary General Eric Drummond to deny Einstein the place on the committee reserved for a Swiss thinker, they created an opening for Gonzague de Reynold , who used his League of Nations position as

13095-442: The mechanisms behind these phenomena. The Greek philosopher Thales of Miletus discovered around 600 B.C.E. that amber could acquire an electric charge when it was rubbed with cloth, which allowed it to pick up light objects such as pieces of straw. Thales also experimented with the ability of magnetic rocks to attract one other, and hypothesized that this phenomenon might be connected to the attractive power of amber, foreshadowing

13230-429: The molecular scale, including its density, is determined by the balance between the electromagnetic force and the force generated by the exchange of momentum carried by the electrons themselves. In 1600, William Gilbert proposed, in his De Magnete , that electricity and magnetism, while both capable of causing attraction and repulsion of objects, were distinct effects. Mariners had noticed that lightning strikes had

13365-468: The molecular theory of heat, continuum mechanics and the development of a relativistic theory of gravitation. In his work on the latter topic, he was assisted by his friend, Marcel Grossmann, whose knowledge of the kind of mathematics required was greater than his own. In the spring of 1913, two German visitors, Max Planck and Walther Nernst , called upon Einstein in Zürich in the hope of persuading him to relocate to Berlin. They offered him membership of

13500-399: The most memorable scenes in the new era of celebrity". Chaplin visited Einstein at his home on a later trip to Berlin and recalled his "modest little flat" and the piano at which he had begun writing his theory. Chaplin speculated that it was "possibly used as kindling wood by the Nazis". In February 1933, while on a visit to the United States, Einstein knew he could not return to Germany with

13635-451: The objects. The effective forces generated by the momentum of electrons' movement is a necessary part of understanding atomic and intermolecular interactions. As electrons move between interacting atoms, they carry momentum with them. As a collection of electrons becomes more confined, their minimum momentum necessarily increases due to the Pauli exclusion principle . The behavior of matter at

13770-421: The phenomena of capillarity"), in which he proposed a model of intermolecular attraction that he afterwards disavowed as worthless, was published in the journal Annalen der Physik in 1901. His 24-page doctoral dissertation also addressed a topic in molecular physics. Titled "Eine neue Bestimmung der Moleküldimensionen" ("A New Determination of Molecular Dimensions") and dedicated to his friend Marcel Grossman, it

13905-452: The potential German nuclear weapons program and recommended that the US begin similar research , though he generally viewed the idea of nuclear weapons with great dismay. In 1905, he published four groundbreaking papers , sometimes described as his annus mirabilis (miracle year). These papers outlined a theory of the photoelectric effect, explained Brownian motion , introduced his special theory of relativity, and demonstrated that if

14040-622: The president of Columbia University , who described Einstein as "the ruling monarch of the mind". Harry Emerson Fosdick , pastor at New York's Riverside Church , gave Einstein a tour of the church and showed him a full-size statue that the church made of Einstein, standing at the entrance. Also during his stay in New York, he joined a crowd of 15,000 people at Madison Square Garden during a Hanukkah celebration. Einstein next traveled to California, where he met Caltech president and Nobel laureate Robert A. Millikan . His friendship with Millikan

14175-419: The process of becoming established and some proposed theories. It can include speculative sciences. This includes physics fields and physical theories presented in accordance with known evidence, and a body of associated predictions have been made according to that theory. Some fringe theories go on to become a widely accepted part of physics. Other fringe theories end up being disproven. Some fringe theories are

14310-408: The publication of James Clerk Maxwell 's 1873 A Treatise on Electricity and Magnetism in which the interactions of positive and negative charges were shown to be mediated by one force. There are four main effects resulting from these interactions, all of which have been clearly demonstrated by experiments: In April 1820, Hans Christian Ørsted observed that an electrical current in a wire caused

14445-420: The question of the extent to which Marić contributed to the insights of Einstein's annus mirabilis publications. There is at least some evidence that he was influenced by her scientific ideas, but there are scholars who doubt whether her impact on his thought was of any great significance at all. Correspondence between Einstein and Marić, discovered and published in 1987, revealed that in early 1902, while Marić

14580-607: The rise of medieval universities , the only acknowledged intellectual disciplines were the seven liberal arts of the Trivium like grammar , logic , and rhetoric and of the Quadrivium like arithmetic , geometry , music and astronomy . During the Middle Ages and Renaissance , the concept of experimental science, the counterpoint to theory, began with scholars such as Ibn al-Haytham and Francis Bacon . As

14715-637: The rise to power of the Nazis under Germany's new chancellor, Adolf Hitler . While at American universities in early 1933, he undertook his third two-month visiting professorship at the California Institute of Technology in Pasadena. In February and March 1933, the Gestapo repeatedly raided his family's apartment in Berlin. He and his wife Elsa returned to Europe in March, and during the trip, they learned that

14850-487: The rolls of institutions where they were employed. A month later, Einstein's works were among those targeted by the German Student Union in the Nazi book burnings , with Nazi propaganda minister Joseph Goebbels proclaiming, "Jewish intellectualism is dead." One German magazine included him in a list of enemies of the German regime with the phrase, "not yet hanged", offering a $ 5,000 bounty on his head. In

14985-471: The same charge, while magnetism is an interaction that occurs between charged particles in relative motion. These two forces are described in terms of electromagnetic fields. Macroscopic charged objects are described in terms of Coulomb's law for electricity and Ampère's force law for magnetism; the Lorentz force describes microscopic charged particles. The electromagnetic force is responsible for many of

15120-712: The seventeenth century. Einstein began his new life as an intellectual icon in America, where he arrived on 2 April 1921. He was welcomed to New York City by Mayor John Francis Hylan , and then spent three weeks giving lectures and attending receptions. He spoke several times at Columbia University and Princeton , and in Washington, he visited the White House with representatives of the National Academy of Sciences . He returned to Europe via London, where he

15255-400: The special theory is correct, mass and energy are equivalent to each other. In 1915, he proposed a general theory of relativity that extended his system of mechanics to incorporate gravitation . A cosmological paper that he published the following year laid out the implications of general relativity for the modeling of the structure and evolution of the universe as a whole. In 1917, he wrote

15390-484: The study of physics which include scientific approaches, means for determining the validity of models and new types of reasoning used to arrive at the theory. However, some proposed theories include theories that have been around for decades and have eluded methods of discovery and testing. Proposed theories can include fringe theories in the process of becoming established (and, sometimes, gaining wider acceptance). Proposed theories usually have not been tested. In addition to

15525-639: The support of several Argentine scholars, including Julio Rey Pastor , Jakob Laub , and Leopoldo Lugones . and was financed primarily by the Council of the University of Buenos Aires and the Asociación Hebraica Argentina (Argentine Hebraic Association) with a smaller contribution from the Argentine-Germanic Cultural Institution. In December 1930, Einstein began another significant sojourn in

15660-472: The theories like those listed below, there are also different interpretations of quantum mechanics , which may or may not be considered different theories since it is debatable whether they yield different predictions for physical experiments, even in principle. For example, AdS/CFT correspondence , Chern–Simons theory , graviton , magnetic monopole , string theory , theory of everything . Fringe theories include any new area of scientific endeavor in

15795-557: The time with him that they requested. After arriving in New York City, Einstein was taken to various places and events, including Chinatown , a lunch with the editors of The New York Times , and a performance of Carmen at the Metropolitan Opera , where he was cheered by the audience on his arrival. During the days following, he was given the keys to the city by Mayor Jimmy Walker and met Nicholas Murray Butler ,

15930-917: The transmission of signals and the synchronization of clocks, matters which also figured in some of the inventions submitted to him for assessment. In 1902, Einstein and some friends whom he had met in Bern formed a group that held regular meetings to discuss science and philosophy. Their choice of a name for their club, the Olympia Academy , was an ironic comment upon its far from Olympian status. Sometimes they were joined by Marić, who limited her participation in their proceedings to careful listening. The thinkers whose works they reflected upon included Henri Poincaré , Ernst Mach and David Hume , all of whom significantly influenced Einstein's own subsequent ideas and beliefs. Einstein's first paper, "Folgerungen aus den Capillaritätserscheinungen" ("Conclusions drawn from

16065-539: The vision provided by pure mathematical systems can provide clues to how a physical system might be modeled; e.g., the notion, due to Riemann and others, that space itself might be curved. Theoretical problems that need computational investigation are often the concern of computational physics . Theoretical advances may consist in setting aside old, incorrect paradigms (e.g., aether theory of light propagation, caloric theory of heat, burning consisting of evolving phlogiston , or astronomical bodies revolving around

16200-530: The works of these men (alongside Galileo's) can perhaps be considered to constitute the Scientific Revolution. The great push toward the modern concept of explanation started with Galileo , one of the few physicists who was both a consummate theoretician and a great experimentalist . The analytic geometry and mechanics of Descartes were incorporated into the calculus and mechanics of Isaac Newton , another theoretician/experimentalist of

16335-428: Was "awkward", as Millikan "had a penchant for patriotic militarism", where Einstein was a pronounced pacifist . During an address to Caltech's students, Einstein noted that science was often inclined to do more harm than good. This aversion to war also led Einstein to befriend author Upton Sinclair and film star Charlie Chaplin , both noted for their pacifism. Carl Laemmle , head of Universal Studios , gave Einstein

16470-621: Was a fractious pupil who found the Gymnasium's regimen and teaching methods far from congenial. He later wrote that the school's policy of strict rote learning was harmful to creativity. At the end of December 1894, a letter from a doctor persuaded the Luitpold's authorities to release him from its care, and he joined his family in Pavia. While in Italy as a teenager, he wrote an essay entitled "On

16605-406: Was an electromagnetic wave propagating in the luminiferous ether . In classical electromagnetism, the behavior of the electromagnetic field is described by a set of equations known as Maxwell's equations , and the electromagnetic force is given by the Lorentz force law . One of the peculiarities of classical electromagnetism is that it is difficult to reconcile with classical mechanics , but it

16740-406: Was born in Bern , Switzerland. Their son Eduard was born in Zürich in July 1910. In letters that Einstein wrote to Marie Winteler in the months before Eduard's arrival, he described his love for his wife as "misguided" and mourned the "missed life" that he imagined he would have enjoyed if he had married Winteler instead: "I think of you in heartfelt love every spare minute and am so unhappy as only

16875-466: Was briefly in a relationship with Margarita Konenkova, thought by some to be a Russian spy; her husband, the Russian sculptor Sergei Konenkov , created the bronze bust of Einstein at the Institute for Advanced Study at Princeton. Following an episode of acute mental illness at about the age of twenty, Einstein's son Eduard was diagnosed with schizophrenia . He spent the remainder of his life either in

17010-632: Was completed on 30 April 1905 and approved by Professor Alfred Kleiner of the University of Zurich three months later. (Einstein was formally awarded his PhD on 15 January 1906.) Four other pieces of work that Einstein completed in 1905— his famous papers on the photoelectric effect , Brownian motion , his special theory of relativity and the equivalence of mass and energy —have led to the year being celebrated as an annus mirabilis for physics akin to 1666 (the year in which Isaac Newton experienced his greatest epiphanies). The publications deeply impressed Einstein's contemporaries. Einstein's sabbatical as

17145-515: Was concerned with the Lorentz transformation which left Maxwell's equations invariant, but was apparently uninterested in the Michelson–Morley experiment on Earth 's drift through a luminiferous aether . Conversely, Einstein was awarded the Nobel Prize for explaining the photoelectric effect , previously an experimental result lacking a theoretical formulation. A physical theory

17280-611: Was diagnosed with heart and kidney problems. She died in December 1936. A volume of Einstein's letters released by Hebrew University of Jerusalem in 2006 added further names to the catalog of women with whom he was romantically involved. They included Margarete Lebach (a married Austrian), Estella Katzenellenbogen (the rich owner of a florist business), Toni Mendel (a wealthy Jewish widow) and Ethel Michanowski (a Berlin socialite), with whom he spent time and from whom he accepted gifts while married to Löwenthal. After being widowed, Einstein

17415-698: Was elected an International Honorary Member of the American Academy of Arts and Sciences . Britain's closest equivalent of the Nobel award, the Royal Society 's Copley Medal , was not hung around Einstein's neck until 1925. He was elected an International Member of the American Philosophical Society in 1930. Einstein resigned from the Prussian Academy in March 1933. His accomplishments in Berlin had included

17550-422: Was given a kinematic explanation by general relativity . Quantum mechanics led to an understanding of blackbody radiation (which indeed, was an original motivation for the theory) and of anomalies in the specific heats of solids — and finally to an understanding of the internal structures of atoms and molecules . Quantum mechanics soon gave way to the formulation of quantum field theory (QFT), begun in

17685-475: Was reported by a Dr. Cookson. The account stated: A tradesman at Wakefield in Yorkshire, having put up a great number of knives and forks in a large box ... and having placed the box in the corner of a large room, there happened a sudden storm of thunder, lightning, &c. ... The owner emptying the box on a counter where some nails lay, the persons who took up the knives, that lay on the nails, observed that

17820-493: Was so great that at twelve, he was already confident that nature could be understood as a "mathematical structure". At thirteen, when his range of enthusiasms had broadened to include music and philosophy, Talmud introduced Einstein to Kant 's Critique of Pure Reason . Kant became his favorite philosopher; according to Talmud, "At the time he was still a child, only thirteen years old, yet Kant's works, incomprehensible to ordinary mortals, seemed to be clear to him." In 1895, at

17955-627: Was the guest of the philosopher and statesman Viscount Haldane . He used his time in the British capital to meet several people prominent in British scientific, political or intellectual life, and to deliver a lecture at King's College . In July 1921, he published an essay, "My First Impression of the U.S.A.", in which he sought to sketch the American character, much as had Alexis de Tocqueville in Democracy in America (1835). He wrote of his transatlantic hosts in highly approving terms: "What strikes

18090-482: Was unable to go to Stockholm in the December of that year to participate in the Nobel prize ceremony. His place at the traditional Nobel banquet was taken by a German diplomat, who gave a speech praising him not only as a physicist but also as a campaigner for peace. A two-week visit to Spain that he undertook in 1923 saw him collecting another award, a membership of the Spanish Academy of Sciences signified by

18225-508: Was visiting her parents in Novi Sad , she gave birth to a daughter, Lieserl . When Marić returned to Switzerland it was without the child, whose fate is uncertain. A letter of Einstein's that he wrote in September 1903 suggests that the girl was either given up for adoption or died of scarlet fever in infancy. Einstein and Marić married in January 1903. In May 1904, their son Hans Albert

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