Paul Sophus Epstein
Encyclopedia
Paul Sophus Epstein was a Russian-American mathematical physicist
. He was known for his contributions to the development of quantum mechanics
, part of a group that included Lorentz
, Einstein
, Minkowski
, Thompson
, Rutherford
, Sommerfeld
, Röntgen, von Laue
, Bohr
, de Broglie, Ehrenfest
and Schwarzschild
.
Paul Epstein's parents, Siegmund Simon Epstein and Sarah Sophia (Lurie) Epstein were of a middle class Jewish family. He said that his mother recognized his potential at four years old and predicted that he would be a mathematician. He went to the Hochschule
in Minsk
, and from 1901-1905 studied mathematics
and physics
at the Imperial University of Moscow
under Pyotr Nikolaevich Lebedev
. In 1909 he graduated, and became a Privatdozent
at the University of Moscow. In 1910 he went to Munich
, Germany, to do research under Arnold Sommerfeld
, who was his advisor, and Epstein was granted a Ph.D. on a problem in the theory of diffraction
of electromagnetic waves. from the Technische Universität München, in 1914. At the outbreak of World War I he was in Munich, and considered an "enemy alien". Thanks to Sommerfeld's intervention he was allowed to stay in Munich as a private citizen, and could continue with his research. By that time Epstein became interested in the quantum theory
of atomic structure. In 1916, he published a seminal paper explaining the Stark effect
using the Bohr Sommerfeld
("old") quantum theory.
After the war he went to Leiden, to become Hendrik Lorentz
' and Paul Ehrenfest
's assistant. In 1921 he was recruited by Robert Millikan
to come to the California Institute of Technology
, where he remained for the rest of his career. In 1922 he published 3 papers on Bohr's quantum mechanics in the Zeitschrift fur Physik
and one in the Physical Review
. In 1926 he published the paper "The Stark Effect from the Point of View of Schrodinger's Quantum Theory" in the Physical Review, as well as "The New Quantum Theory and the Zeeman Effect" (1926), and "The Magnetic Dipole in Undulatory Mechanics" (1927).
In 1920 Epstein calculated the effect of Polflucht
as a possible causing force of Wegeners
continental drift
. His value was about 10^-6 of the gravitational force. Some years later other geophysicists could show that the Polflucht force is far too weak to cause plate tectonics
. The toughness of the sublayers of the Earth's crust is much more stronger than assumed by Epstein.
In 1930 he was elected a member of the National Academy of Sciences
. In 1930, Epstein married Alice Emelie Ryckman, and the couple had a daughter Sari (Mittelbach). After World War II, concerned that some young American intellectuals were becoming attracted to communism
, he joined the American Committee of the Congress for Cultural Freedom and in 1951 he served as on of the three US delegates to the seminar the Congress held in Strasbourg
.
As well as quantum theory, Epstein also published papers in other fields. Examples include ""Zur Theorie des Radiometers" (1929), "Reflection of Waves in an Inhomogeneous Absorbing Medium" (1930) and "On the Air Resistance of Projectiles" (1931). Other subjects that he worked on were the settling of gases in the atmosphere, the theory of vibrations of shells and plates and the absorption of sound in fogs and suspensions. He retired as Emeritus Professor at Caltech in 1953 and continued to serve as a consultant for a number of industrial companies. One of the significant reports he wrote during this period was "Theory of Wave Propagation in a Gyromagnetic Medium" (1956).
Epstein had other interests as well. He was very interested in Freudian psychology and was one of the founding members of a Psychoanalytic Study Group (together with Thomas Libbin) that later merged into the Los Angeles Institute for Psychoanalysis. In the 1930s he published two articles in the monthly literary and scientific magazine Reflex - "The Frontiers of Science" and "Uses and Abuses of Nationalism". Although he was not an active Zionist
, Epstein served as a member of the American National Society of Friends of the Hebrew University and was very friendly with the prominent Israel
i mathematician Abraham Fraenkel. The Epstein Memorial Fund was established through donations from more than fifty of his former students and a bronze bust of Epstein stands in the Physics and Mathematics section of the Millikan library at Caltech.
Mathematical physics
Mathematical physics refers to development of mathematical methods for application to problems in physics. The Journal of Mathematical Physics defines this area as: "the application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and...
. He was known for his contributions to the development of quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...
, part of a group that included Lorentz
Hendrik Lorentz
Hendrik Antoon Lorentz was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect...
, Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
, Minkowski
Hermann Minkowski
Hermann Minkowski was a German mathematician of Ashkenazi Jewish descent, who created and developed the geometry of numbers and who used geometrical methods to solve difficult problems in number theory, mathematical physics, and the theory of relativity.- Life and work :Hermann Minkowski was born...
, Thompson
Thompson (surname)
Thompson is a patronymic surname of English origin, with a variety of spellings meaning "son of Tom ". It is the 14th-most common surname in the United Kingdom...
, Rutherford
Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson OM, FRS was a New Zealand-born British chemist and physicist who became known as the father of nuclear physics...
, Sommerfeld
Arnold Sommerfeld
Arnold Johannes Wilhelm Sommerfeld was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and groomed a large number of students for the new era of theoretical physics...
, Röntgen, von Laue
Max von Laue
Max Theodor Felix von Laue was a German physicist who won the Nobel Prize in Physics in 1914 for his discovery of the diffraction of X-rays by crystals...
, Bohr
Niels Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in...
, de Broglie, Ehrenfest
Paul Ehrenfest
Paul Ehrenfest was an Austrian and Dutch physicist, who made major contributions to the field of statistical mechanics and its relations with quantum mechanics, including the theory of phase transition and the Ehrenfest theorem.- Biography :Paul Ehrenfest was born and grew up in Vienna in a Jewish...
and Schwarzschild
Karl Schwarzschild
Karl Schwarzschild was a German physicist. He is also the father of astrophysicist Martin Schwarzschild.He is best known for providing the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished...
.
Paul Epstein's parents, Siegmund Simon Epstein and Sarah Sophia (Lurie) Epstein were of a middle class Jewish family. He said that his mother recognized his potential at four years old and predicted that he would be a mathematician. He went to the Hochschule
Hochschule
Hochschule is a German term with two meanings.The literal meaning of the word Hochschule is “high school” which is not appropriate as a translation.- Generic term :...
in Minsk
Minsk
- Ecological situation :The ecological situation is monitored by Republican Center of Radioactive and Environmental Control .During 2003–2008 the overall weight of contaminants increased from 186,000 to 247,400 tons. The change of gas as industrial fuel to mazut for financial reasons has worsened...
, and from 1901-1905 studied mathematics
Mathematics
Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...
and physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
at the Imperial University of Moscow
Moscow State University
Lomonosov Moscow State University , previously known as Lomonosov University or MSU , is the largest university in Russia. Founded in 1755, it also claims to be one of the oldest university in Russia and to have the tallest educational building in the world. Its current rector is Viktor Sadovnichiy...
under Pyotr Nikolaevich Lebedev
Pyotr Nikolaevich Lebedev
Pyotr Nikolaevich Lebedev was a Russian physicist.He made his doctoral degree in Strasbourg under the supervision of August Kundt in 1887–1891. In 1891 he started working in Moscow State University in the group of Alexander Stoletov. There he made his famous experimental studies of...
. In 1909 he graduated, and became a Privatdozent
Privatdozent
Privatdozent or Private lecturer is a title conferred in some European university systems, especially in German-speaking countries, for someone who pursues an academic career and holds all formal qualifications to become a tenured university professor...
at the University of Moscow. In 1910 he went to Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
, Germany, to do research under Arnold Sommerfeld
Arnold Sommerfeld
Arnold Johannes Wilhelm Sommerfeld was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and groomed a large number of students for the new era of theoretical physics...
, who was his advisor, and Epstein was granted a Ph.D. on a problem in the theory of diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...
of electromagnetic waves. from the Technische Universität München, in 1914. At the outbreak of World War I he was in Munich, and considered an "enemy alien". Thanks to Sommerfeld's intervention he was allowed to stay in Munich as a private citizen, and could continue with his research. By that time Epstein became interested in the quantum theory
Bohr model
In atomic physics, the Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with electrostatic forces providing attraction,...
of atomic structure. In 1916, he published a seminal paper explaining the Stark effect
Stark effect
The Stark effect is the shifting and splitting of spectral lines of atoms and molecules due to presence of an external static electric field. The amount of splitting and or shifting is called the Stark splitting or Stark shift. In general one distinguishes first- and second-order Stark effects...
using the Bohr Sommerfeld
Bohr model
In atomic physics, the Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with electrostatic forces providing attraction,...
("old") quantum theory.
After the war he went to Leiden, to become Hendrik Lorentz
Hendrik Lorentz
Hendrik Antoon Lorentz was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect...
' and Paul Ehrenfest
Paul Ehrenfest
Paul Ehrenfest was an Austrian and Dutch physicist, who made major contributions to the field of statistical mechanics and its relations with quantum mechanics, including the theory of phase transition and the Ehrenfest theorem.- Biography :Paul Ehrenfest was born and grew up in Vienna in a Jewish...
's assistant. In 1921 he was recruited by Robert Millikan
Robert Millikan
Robert A. Millikan was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as president of Caltech from 1921 to 1945...
to come to the California Institute of Technology
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
, where he remained for the rest of his career. In 1922 he published 3 papers on Bohr's quantum mechanics in the Zeitschrift fur Physik
Zeitschrift für Physik
The European Physical Journal is a joint publication of EDP Sciences, Springer Science+Business Media, and the Società Italiana di Fisica...
and one in the Physical Review
Physical Review
Physical Review is an American scientific journal founded in 1893 by Edward Nichols. It publishes original research and scientific and literature reviews on all aspects of physics. It is published by the American Physical Society. The journal is in its third series, and is split in several...
. In 1926 he published the paper "The Stark Effect from the Point of View of Schrodinger's Quantum Theory" in the Physical Review, as well as "The New Quantum Theory and the Zeeman Effect" (1926), and "The Magnetic Dipole in Undulatory Mechanics" (1927).
In 1920 Epstein calculated the effect of Polflucht
Polflucht
Polflucht is a geophysical concept invoked 1915 by Alfred Wegener to explain his ideas of Continental drift...
as a possible causing force of Wegeners
Alfred Wegener
Alfred Lothar Wegener was a German scientist, geophysicist, and meteorologist.He is most notable for his theory of continental drift , proposed in 1912, which hypothesized that the continents were slowly drifting around the Earth...
continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...
. His value was about 10^-6 of the gravitational force. Some years later other geophysicists could show that the Polflucht force is far too weak to cause plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
. The toughness of the sublayers of the Earth's crust is much more stronger than assumed by Epstein.
In 1930 he was elected a member of the National Academy of Sciences
United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
. In 1930, Epstein married Alice Emelie Ryckman, and the couple had a daughter Sari (Mittelbach). After World War II, concerned that some young American intellectuals were becoming attracted to communism
Communism
Communism is a social, political and economic ideology that aims at the establishment of a classless, moneyless, revolutionary and stateless socialist society structured upon common ownership of the means of production...
, he joined the American Committee of the Congress for Cultural Freedom and in 1951 he served as on of the three US delegates to the seminar the Congress held in Strasbourg
Strasbourg
Strasbourg is the capital and principal city of the Alsace region in eastern France and is the official seat of the European Parliament. Located close to the border with Germany, it is the capital of the Bas-Rhin département. The city and the region of Alsace are historically German-speaking,...
.
As well as quantum theory, Epstein also published papers in other fields. Examples include ""Zur Theorie des Radiometers" (1929), "Reflection of Waves in an Inhomogeneous Absorbing Medium" (1930) and "On the Air Resistance of Projectiles" (1931). Other subjects that he worked on were the settling of gases in the atmosphere, the theory of vibrations of shells and plates and the absorption of sound in fogs and suspensions. He retired as Emeritus Professor at Caltech in 1953 and continued to serve as a consultant for a number of industrial companies. One of the significant reports he wrote during this period was "Theory of Wave Propagation in a Gyromagnetic Medium" (1956).
Epstein had other interests as well. He was very interested in Freudian psychology and was one of the founding members of a Psychoanalytic Study Group (together with Thomas Libbin) that later merged into the Los Angeles Institute for Psychoanalysis. In the 1930s he published two articles in the monthly literary and scientific magazine Reflex - "The Frontiers of Science" and "Uses and Abuses of Nationalism". Although he was not an active Zionist
Zionism
Zionism is a Jewish political movement that, in its broadest sense, has supported the self-determination of the Jewish people in a sovereign Jewish national homeland. Since the establishment of the State of Israel, the Zionist movement continues primarily to advocate on behalf of the Jewish state...
, Epstein served as a member of the American National Society of Friends of the Hebrew University and was very friendly with the prominent Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...
i mathematician Abraham Fraenkel. The Epstein Memorial Fund was established through donations from more than fifty of his former students and a bronze bust of Epstein stands in the Physics and Mathematics section of the Millikan library at Caltech.
External links
- Jesse W.M. DuMond, Paul Sophus Epstein, Biographical Memoirs V.45 (1974), National Academy of Sciences (NAS)
- Caltech Archives Oral Histories Online Interview with Paul S. Epstein
- Oral History interview transcript with Paul Sophus Epstein, 25, 26 May & 2 June 1962, American Institute of Physics, Niels Bohr Library and Archives