|
BCFW Recursion
The Britto–Cachazo–Feng–Witten recursion relations are a set of on-shell recursion relations in quantum field theory. They are named for their creators, Ruth Britto, Freddy Cachazo, Bo Feng and Edward Witten. The BCFW recursion method is a way of calculating scattering amplitudes. This technique is widely used in analytic calculations due to the relative conciseness of the resulting expressions, when compared to the more traditional methods. The principal property of the BCFW recursion is that at every stage of the calculation it involves exclusively real (on-shell) particles, as opposed to the virtual (off-shell) particles that propagate inside conventional Feynman diagrams In theoretical physics, a Feynman diagram is a pictorial representation of the mathematical expressions describing the behavior and interaction of subatomic particles. The scheme is named after American physicist Richard Feynman, who introduce .... See also * MHV amplitudes References Qu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
On-shell
In physics, particularly in quantum field theory, configurations of a physical system that satisfy classical equations of motion are called "on the mass shell" or simply more often on shell; while those that do not are called "off the mass shell", or off shell. In quantum field theory, virtual particles are termed off shell because they do not satisfy the energy–momentum relation; real exchange particles do satisfy this relation and are termed on shell (mass shell). In classical mechanics for instance, in the action (physics), action formulation, extremal solutions to the variational principle are on shell and the Euler–Lagrange equations give the on-shell equations. Noether's theorem regarding differentiable symmetries of physical action and conservation laws is another on-shell theorem. Mass shell Mass shell is a synonym for mass hyperboloid, meaning the hyperboloid in energy–momentum space describing the solutions to the equation: :E^2 - , \vec \,, ^2 c^2 = m_0^2 c^ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recursion Relation
In mathematics, a recurrence relation is an equation according to which the nth term of a sequence of numbers is equal to some combination of the previous terms. Often, only k previous terms of the sequence appear in the equation, for a parameter k that is independent of n; this number k is called the ''order'' of the relation. If the values of the first k numbers in the sequence have been given, the rest of the sequence can be calculated by repeatedly applying the equation. In ''linear recurrences'', the th term is equated to a linear function of the k previous terms. A famous example is the recurrence for the Fibonacci numbers, F_n=F_+F_ where the order k is two and the linear function merely adds the two previous terms. This example is a linear recurrence with constant coefficients, because the coefficients of the linear function (1 and 1) are constants that do not depend on n. For these recurrences, one can express the general term of the sequence as a closed-form expression of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Field Theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles. QFT treats particles as excited states (also called Quantum, quanta) of their underlying quantum field (physics), fields, which are more fundamental than the particles. The equation of motion of the particle is determined by minimization of the Lagrangian, a functional of fields associated with the particle. Interactions between particles are described by interaction terms in the Lagrangian (field theory), Lagrangian involving their corresponding quantum fields. Each interaction can be visually represented by Feynman diagrams according to perturbation theory (quantum mechanics), perturbation theory in quantum mechanics. History Quantum field theory emerged from the wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruth Britto
Ruth Alexandra Britto-Pacumio is an American mathematical physicist whose research topics include black holes, Yang–Mills theory, and the theory of Feynman integrals; with Freddy Cachazo, Bo Feng, and Edward Witten she is one of the namesakes of the BCFW recursion relations for computing scattering amplitudes. She is an associate professor in mathematics and theoretical physics at Trinity College Dublin, and is also affiliated with the Institut de Physique Théorique of CEA Saclay. Education and career Britto is originally from Binghamton, New York, where her father, Ronald Britto, was a professor of economics at Binghamton University. As an undergraduate mathematics student at the Massachusetts Institute of Technology, she was the 1994 winner of the Elizabeth Lowell Putnam Prize for the best performance by a female student in the William Lowell Putnam Mathematical Competition, and the 1995 winner of the Alice T. Schafer Prize for Excellence in Mathematics by an Undergraduate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freddy Cachazo
Freddy Alexander Cachazo is a Venezuelan-born theoretical physicist who holds the Gluskin Sheff Freeman Dyson Chair in Theoretical Physics at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada. He is known for the contributions to quantum field theory through the study of scattering amplitudes, in particular in quantum chromodynamics, N = 4 supersymmetric Yang–Mills theory and quantum gravity. His contributions include BCFW recursion relations, the CSW vertex expansion and the amplituhedron. In 2014, Cachazo was awarded the New Horizons Prize for ''uncovering numerous structures underlying scattering amplitudes in gauge theories and gravity''. Academic career After graduating from Simón Bolívar University in 1996, Cachazo attended a year-long Postgraduate Diploma Programme at the International Centre for Theoretical Physics (ICTP) in Trieste, Italy. He was admitted in Harvard University, where he completed the Ph.D. under the supervision of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bo Feng
Bo or BO may refer to Arts and entertainment Film, television, and theatre * Box office, where tickets to an event are sold, and by extension, the amount of business a production receives *'' BA:BO'', 2008 South Korean film * ''Bo'' (film), a Belgian film starring Ella-June Henrard and directed by Hans Herbots Gaming *'' Call of Duty: Black Ops'', a first-person shooter video game *'' Blood Omen: Legacy of Kain'', first in the Legacy of Kain video game series Music * Bo (instrument), a Chinese cymbal * Bo, a Greek rapper. Religion *Bo or Bodhi Tree *Bo (parsha), fifteenth weekly Torah reading Ethnic groups *Bo people (China), a nearly extinct minority population in Southern China *Bo people of Laos, see List of ethnic groups in Laos * Bo people (Andaman), a recently extinct group in the Andaman Islands Human names * Bo (given name), name origin, plus a list of people and fictional characters with the name or nickname * Bo (surname), name origin, plus a list of people with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edward Witten
Edward Witten (born August 26, 1951) is an American mathematical and theoretical physicist. He is a Professor Emeritus in the School of Natural Sciences at the Institute for Advanced Study in Princeton. Witten is a researcher in string theory, quantum gravity, supersymmetric quantum field theories, and other areas of mathematical physics. Witten's work has also significantly impacted pure mathematics. In 1990, he became the first physicist to be awarded a Fields Medal by the International Mathematical Union, for his mathematical insights in physics, such as his 1981 proof of the positive energy theorem in general relativity, and his interpretation of the Jones invariants of knots as Feynman integrals. He is considered the practical founder of M-theory.Duff 1998, p. 65 Early life and education Witten was born on August 26, 1951, in Baltimore, Maryland, to a Jewish family. He is the son of Lorraine (née Wollach) Witten and Louis Witten, a theoretical physicist specializing in gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scattering Amplitude
In quantum physics, the scattering amplitude is the probability amplitude of the outgoing spherical wave relative to the incoming plane wave in a stationary-state scattering process. By Nouredine Zettili, 2nd edition, page 623. Paperback 688 pages January 2009 The plane wave is described by the : where is the position vector; ; is the incoming plane wave with the |
Feynman Diagram
In theoretical physics, a Feynman diagram is a pictorial representation of the mathematical expressions describing the behavior and interaction of subatomic particles. The scheme is named after American physicist Richard Feynman, who introduced the diagrams in 1948. The interaction of subatomic particles can be complex and difficult to understand; Feynman diagrams give a simple visualization of what would otherwise be an arcane and abstract formula. According to David Kaiser, "Since the middle of the 20th century, theoretical physicists have increasingly turned to this tool to help them undertake critical calculations. Feynman diagrams have revolutionized nearly every aspect of theoretical physics." While the diagrams are applied primarily to quantum field theory, they can also be used in other fields, such as solid-state theory. Frank Wilczek wrote that the calculations that won him the 2004 Nobel Prize in Physics "would have been literally unthinkable without Feynman diagra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Field Theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles. QFT treats particles as excited states (also called Quantum, quanta) of their underlying quantum field (physics), fields, which are more fundamental than the particles. The equation of motion of the particle is determined by minimization of the Lagrangian, a functional of fields associated with the particle. Interactions between particles are described by interaction terms in the Lagrangian (field theory), Lagrangian involving their corresponding quantum fields. Each interaction can be visually represented by Feynman diagrams according to perturbation theory (quantum mechanics), perturbation theory in quantum mechanics. History Quantum field theory emerged from the wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
