Albert Einstein


Albert Einstein was a German-born theoretical physicist best known for developing the theory of relativity. Einstein also made important contributions to quantum theory. His mass–energy equivalence formula, which arises from special relativity, has been called "the world's most famous equation". He received the 1921 Nobel Prize in Physics for "his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect".
Born in the German Empire, Einstein moved to Switzerland in 1895, forsaking his German citizenship the following year. In 1897, at the age of seventeen, he enrolled in the mathematics and physics teaching diploma program at the Swiss federal polytechnic school in Zurich, graduating in 1900. He acquired Swiss citizenship a year later, which he kept for the rest of his life, and afterwards secured a permanent position at the Swiss Patent Office in Bern. In 1905, he submitted a successful PhD dissertation to the University of Zurich. In 1914, he moved to Berlin to join the Prussian Academy of Sciences and the Humboldt University of Berlin, becoming director of the Kaiser Wilhelm Institute for Physics in 1917; he also became a German citizen again, this time as a subject of the Kingdom of Prussia. 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, he decided to remain in the US, and was granted American citizenship in 1940. On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential German nuclear weapons program and recommending that the US begin similar research, later carried out as the Manhattan Project.
In 1905, sometimes described as his annus mirabilis, he published four groundbreaking papers. In them, he outlined a theory of the photoelectric effect, explained Brownian motion, introduced his special theory of relativity, and demonstrated that if 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 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. It introduced the cosmological constant and is further regarded as the first step in the field of modern theoretical cosmology. In 1917, Einstein wrote a paper which introduced the concepts of spontaneous emission and stimulated emission, the latter of which is the core mechanism behind the laser and maser, and which contained a trove of information that would be beneficial to developments in physics later on, such as quantum electrodynamics and quantum optics.
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 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 ultimately proved 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 a unified field theory by generalizing his geometric theory of gravitation to include electromagnetism. As a result, he became increasingly isolated from mainstream modern physics. Many things are named after him, including the element Einsteinium. In 1999, he was named Time's Person of the Century.

Life and career

Childhood, youth and education

Albert Einstein was born in Ulm, in the Kingdom of Württemberg in 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.
When he was very young, his parents worried that he had a learning disability because he was very slow to learn to talk. When he was five and sick in bed, his father brought him a compass. This sparked his lifelong fascination with electromagnetism. He realized that "Something deeply hidden had to be behind things."
Einstein 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 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 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 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 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 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 the age of sixteen, Einstein sat the entrance examination for the federal polytechnic school in Zurich, 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 in Aarau, Switzerland, graduating in 1896. While lodging in Aarau with the family of Jost Winteler, he fell in love with Winteler's daughter, Marie.
File:Albert Einstein's exam of maturity grades.jpg|thumb|upright|alt=Einstein's matriculation certificate at the age of 17. The heading translates as "The Education Committee of the Canton of Aargau". His scores were German 5, French 3, Italian 5, History 6, Geography 4, Algebra 6, Geometry 6, Descriptive Geometry 6, Physics 6, Chemistry 5, Natural History 5, Art Drawing 4, Technical Drawing 4. 6 = very good, 5 = good, 4 = sufficient, 3 = insufficient, 2 = poor, 1 = very poor.|Einstein's Matura certificate from canton Aargau, 1896
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, awarded to him in September 1896, acknowledged him to have performed well across most of 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. He befriended fellow student Marcel Grossmann, who would help him there to get by despite his loose study habits, and later to mathematically underpin his revolutionary insights into physics. 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, 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 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.