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Paul Frederick Zweifel
Paul Frederick Zweifel (June 21, 1929 – February 12, 2017) was a mathematical physicist and a prominent leader in the mathematical theory of nuclear reactors and the mathematical development of linear transport theory, a discipline that encompasses neutron transport in the core of a nuclear reactor as well as the propagation of photons in radiative transfer. In transport theory, he pioneered the use of rigorous mathematics for analytically solving the linear transport equation. He developed existence and uniqueness theorems for the neutron transport equation and investigated the spectrum of the linear transport operator under general conditions. Early years Paul Zweifel was born on June 21, 1929, in New York City, to Dorothy and Frederick Zweifel. His family moved to Spartanburg, South Carolina. When he was fifteen, he received the Pepsi-Cola Scholarship to attend the college of his choice, Carnegie Institute of Technology (now Carnegie Mellon University), and graduated wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Transport
Neutron transport (also known as neutronics) is the study of the motions and interactions of neutrons with materials. Nuclear scientists and engineers often need to know where neutrons are in an apparatus, in what direction they are going, and how quickly they are moving. It is commonly used to determine the behavior of nuclear reactor cores and experimental or industrial neutron beams. Neutron transport is a type of radiative transport. Background Neutron transport has roots in the Boltzmann equation, which was used in the 1800s to study the kinetic theory of gases. It did not receive large-scale development until the invention of chain-reacting nuclear reactors in the 1940s. As neutron distributions came under detailed scrutiny, elegant approximations and analytic solutions were found in simple geometries. However, as computational power has increased, numerical approaches to neutron transport have become prevalent. Today, with massively parallel computers, neutron transport ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boltzmann Equation
The Boltzmann equation or Boltzmann transport equation (BTE) describes the statistical behaviour of a thermodynamic system not in a state of equilibrium; it was devised by Ludwig Boltzmann in 1872.Encyclopaedia of Physics (2nd Edition), R. G. Lerner, G. L. Trigg, VHC publishers, 1991, ISBN (Verlagsgesellschaft) 3-527-26954-1, ISBN (VHC Inc.) 0-89573-752-3. The classic example of such a system is a fluid with temperature gradients in space causing heat to flow from hotter regions to colder ones, by the random but biased transport of the particles making up that fluid. In the modern literature the term Boltzmann equation is often used in a more general sense, referring to any kinetic equation that describes the change of a macroscopic quantity in a thermodynamic system, such as energy, charge or particle number. The equation arises not by analyzing the individual positions and momenta of each particle in the fluid but rather by considering a probability distribution for the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manhattan Project
The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada. From 1942 to 1946, the project was directed by Major General Leslie Groves of the United States Army Corps of Engineers, U.S. Army Corps of Engineers. Nuclear physicist J. Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the bombs. The Army program was designated the Manhattan District, as its first headquarters were in Manhattan; the name gradually superseded the official codename, Development of Substitute Materials, for the entire project. The project absorbed its earlier British counterpart, Tube Alloys, and subsumed the program from the American civilian Office of Scientific Research and Development. The Manhattan Project employed nearly 130,000 people at its peak and cost nearly US$2 billion (equivalent to about $ b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kenneth Case
Kenneth Myron Case (September 23, 1923 – February 1, 2006) was an American physicist and applied mathematician, best known for his use of the mathematical methods of quantum field theory (as developed in the 1940s) and transport theory (in part from the Manhattan Project) to a wide range of applied problems, especially many relevant to U.S. national security. He was an early member of the JASON advisory group. Early life and education Case was born in Brooklyn, New York, and grew up in Manhattan. His father was a successful businessman who owned a paint manufacturing company. His mother was from an affluent family of German-Austrian Jews. Case, under the original family name Cassoff, attended the Ethical Culture School and then Fieldston. When he was in high school, his parents changed the family name to Case in the belief that this would improve their son's prospects. Ken was accepted for undergraduate studies at Harvard and matriculated in 1941, exempted from the World War ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emil Konopinski
Emil John (Jan) Konopinski (December 25, 1911 in Michigan City, Indiana – May 26, 1990 in Bloomington, Indiana) was an American nuclear scientist Emil Konopinski, 78, Atomic Bomb Scientist New York Times of Polish descent. His parents were Joseph and Sophia (). He was, with as thesis advisor, a 1934 Ph.D graduate of the , and later a professor of |
George Uhlenbeck
George Eugene Uhlenbeck (December 6, 1900 – October 31, 1988) was a Dutch-American theoretical physicist, known for his significant contributions to quantum mechanics and statistical mechanics. He co-developed the concept of electron spin, alongside Samuel Goudsmit, in 1925. The formalization of Langevin equation for the Brownian motion as a stochastic process, is known as the Ornstein–Uhlenbeck process, derived in 1930 from his work with Leonard Ornstein. I. I. Rabi said that Uhlenbeck and Goudsmit's omission for the Nobel Prize in Physics "will always be a mystery to me". Background and education George Uhlenbeck was the son of Eugenius and Anne Beeger Uhlenbeck. He attended the Hogere Burgerschool (High School) in The Hague, from which he graduated in 1918. He subsequently entered Delft University of Technology as a student in chemical engineering. During the next year, he transferred to Leiden University, to study physics and mathematics, and he earned his bachelor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Ehrenfest
Paul Ehrenfest (; 18 January 1880 – 25 September 1933) was an Austrian Theoretical physics, theoretical physicist who made major contributions to statistical mechanics and its relation to quantum physics, quantum mechanics, including the theory of phase transition and the Ehrenfest theorem. He befriended Albert Einstein on a visit to Prague in 1912 and became a professor in Leiden, where he frequently hosted Einstein. Suffering from depression, in 1933 Ehrenfest killed his disabled son, Wassik, and then himself. Biography Paul Ehrenfest was born on 18 January 1880 in Vienna to Ashkenazi Jews, Jewish parents, who were originally from Loštice in Moravia (now part of the Czech Republic). His parents, Sigmund Ehrenfest and Johanna Jellinek, managed a grocery store. Although the family was not overly religious, Paul studied Hebrew language, Hebrew and Jewish history. Later, he always emphasized his Jewish ancestry. Ehrenfest excelled in grade school but did not do well at the Akad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludwig Boltzmann
Ludwig Eduard Boltzmann ( ; ; 20 February 1844 – 5 September 1906) was an Austrian mathematician and Theoretical physics, theoretical physicist. His greatest achievements were the development of statistical mechanics and the statistical explanation of the second law of thermodynamics. In 1877 he provided the current definition of entropy, S = k_ \ln \Omega, where Ω is the number of microstates whose energy equals the system's energy, interpreted as a measure of the statistical disorder of a system. Max Planck named the constant the Boltzmann constant. Statistical mechanics is one of the pillars of modern physics. It describes how macroscopic observations (such as temperature and pressure) are related to microscopic parameters that fluctuate around an average. It connects thermodynamic quantities (such as heat capacity) to microscopic behavior, whereas, in classical thermodynamics, the only available option would be to measure and tabulate such quantities for various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josef Stefan
Josef Stefan (; 24 March 1835 – 7 January 1893) was a Carinthian Slovene physicist, mathematician, and poet of the Austrian Empire. Life and work Stefan was born in the village of St. Peter (Slovene: ) on the outskirts of Klagenfurt) to Aleš (Aleksander) Stefan (1805-1872) and Marija Startinik (1815-1863). His parents, both ethnic Slovenes, did not marry until Josef was eleven. The Stefans were of modest means; his father was a milling assistant and his mother served as a maidservant. Josef was their only child. Stefan attended elementary school in Klagenfurt, where he showed talent, and was recommended for enrollment at the in 1845. At thirteen, he experienced the revolutionary year of 1848, which inspired him to show sympathy toward the Slovene literary and national movement. After having graduated top of his class in high school, he briefly considered joining the Benedictine Order, but his great interest in physics prevailed. He left for Vienna in 1853 to study mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnegie Mellon University
Carnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania, United States. The institution was established in 1900 by Andrew Carnegie as the Carnegie Technical Schools. In 1912, it became the Carnegie Institute of Technology and began granting four-year degrees. In 1967, it became Carnegie Mellon University through its merger with the Mellon Institute of Industrial Research, founded in 1913 by Andrew Mellon and Richard B. Mellon and formerly a part of the University of Pittsburgh. The university consists of seven colleges, including the College of Engineering, the School of Computer Science, and the Tepper School of Business. The university has its main campus located 5 miles (8 km) from downtown Pittsburgh. It also has over a dozen degree-granting locations in six continents, including campuses in Qatar, Silicon Valley, and Kigali, Rwanda ( Carnegie Mellon University Africa) and partnerships with universities nationally and glob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Carolina
South Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders North Carolina to the north and northeast, the Atlantic Ocean to the southeast, and Georgia (U.S. state), Georgia to the west and south across the Savannah River. Along with North Carolina, it makes up the Carolinas region of the East Coast of the United States, East Coast. South Carolina is the List of U.S. states and territories by area, 11th-smallest and List of U.S. states and territories by population, 23rd-most populous U.S. state with a recorded population of 5,118,425 according to the 2020 United States census, 2020 census. In , its GDP was $213.45 billion. South Carolina is composed of List of counties in South Carolina, 46 counties. The capital is Columbia, South Carolina, Columbia with a population of 136,632 in 2020; while its List of municipalities in South Carolina, most populous city is Charleston, South Carolina, Charleston with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
