In mathematics and applied mathematics, perturbation theory comprises methods for finding an approximate solution to a problem, by starting from the exact... 22 KB (2,933 words) - 21:08, 29 April 2024 |
In quantum mechanics, perturbation theory is a set of approximation schemes directly related to mathematical perturbation for describing a complicated... 70 KB (15,890 words) - 21:15, 8 May 2024 |
cosmological perturbation theory is the theory by which the evolution of structure is understood in the Big Bang model. Cosmological perturbation theory may be... 15 KB (2,050 words) - 13:23, 28 October 2023 |
Møller–Plesset perturbation theory (MP) is one of several quantum chemistry post-Hartree–Fock ab initio methods in the field of computational chemistry... 23 KB (2,870 words) - 20:17, 25 November 2023 |
Chiral perturbation theory (ChPT) is an effective field theory constructed with a Lagrangian consistent with the (approximate) chiral symmetry of quantum... 10 KB (1,506 words) - 18:11, 25 July 2023 |
Look up perturbation or perturb in Wiktionary, the free dictionary. Perturbation or perturb may refer to: Perturbation theory, mathematical methods that... 952 bytes (149 words) - 10:41, 23 May 2018 |
Frontier molecular orbital theory Ligand field theory (MO theory for transition metal complexes) Møller–Plesset perturbation theory Quantum chemistry computer... 22 KB (2,943 words) - 18:31, 27 April 2024 |
without derivatives. This means that one can manage this theory only by perturbation theory with small nonlinearities.[citation needed] Note that the... 28 KB (4,217 words) - 00:17, 4 May 2024 |
In solid-state physics, the k·p perturbation theory is an approximated semi-empirical approach for calculating the band structure (particularly effective... 12 KB (1,975 words) - 11:29, 25 March 2024 |
straightforwardly defined using the techniques of perturbation theory, but it is not known in general how to define string theory nonperturbatively. It is also not clear... 123 KB (15,352 words) - 18:50, 24 April 2024 |
In mathematics, variational perturbation theory (VPT) is a mathematical method to convert divergent power series in a small expansion parameter, say s... 4 KB (428 words) - 13:36, 16 December 2020 |
In mathematics and electronics, cavity perturbation theory describes methods for derivation of perturbation formulae for performance changes of a cavity... 16 KB (1,924 words) - 13:50, 24 March 2024 |
In mathematics, a singular perturbation problem is a problem containing a small parameter that cannot be approximated by setting the parameter value to... 11 KB (1,779 words) - 20:02, 14 January 2024 |
theory — Perturbation theory — Potential theory — Probability theory — Ramsey theory — Rational choice theory — Representation theory — Ring theory —... 38 KB (4,353 words) - 00:15, 15 April 2024 |
Stark effect (section Perturbation theory) the Stark effect in his third paper on quantum theory (in which he introduced his perturbation theory), once in the manner of the 1916 work of Epstein... 18 KB (2,744 words) - 16:57, 30 October 2023 |
respected by the theory. An example is the spectral line splitting in the Zeeman effect, due to a magnetic interaction perturbation in the Hamiltonian... 3 KB (472 words) - 00:20, 22 June 2022 |
In mathematics, an eigenvalue perturbation problem is that of finding the eigenvectors and eigenvalues of a system A x = λ x {\displaystyle Ax=\lambda... 27 KB (6,234 words) - 06:43, 8 February 2024 |
theories used for these types of equations of state are the Barker-Henderson perturbation theory and the Weeks–Chandler–Andersen perturbation theory.... 38 KB (5,388 words) - 05:55, 25 April 2024 |
Celestial mechanics (section Perturbation theory) cases the approximation only applies after arrival at that orbit) Perturbation theory comprises mathematical methods that are used to find an approximate... 18 KB (2,194 words) - 18:29, 19 February 2024 |
Quantum gravity (redirect from Quantum theory of gravity) background. In this sense, string perturbation theory exhibits exactly the features one would expect of a perturbation theory that may exhibit a strong dependence... 59 KB (6,684 words) - 09:49, 6 May 2024 |
Causal perturbation theory is a mathematically rigorous approach to renormalization theory, which makes it possible to put the theoretical setup of perturbative... 4 KB (467 words) - 04:22, 6 February 2024 |
Pressure coefficient (section Perturbation theory) classical piston theory is a powerful aerodynamic tool. From the use of the momentum equation and the assumption of isentropic perturbations, one obtains... 9 KB (1,645 words) - 20:39, 17 February 2024 |
Kolmogorov–Arnold–Moser theorem (redirect from Kam theory) motions under small perturbations. The theorem partly resolves the small-divisor problem that arises in the perturbation theory of classical mechanics... 9 KB (1,204 words) - 14:21, 9 June 2023 |
Schrieffer–Wolff transformation is an operator version of second-order perturbation theory. The Schrieffer–Wolff transformation is often used to project out... 12 KB (2,124 words) - 17:07, 8 May 2024 |
the effective field theory of QCD called chiral perturbation theory has had better success. This theory deals with the interactions of hadrons with pions... 12 KB (1,488 words) - 08:09, 14 May 2024 |
Electronic band structure (redirect from Band theory) a region of free space that has been divided into a lattice. k·p perturbation theory is a technique that allows a band structure to be approximately described... 36 KB (4,772 words) - 18:25, 25 March 2024 |
Hartree–Fock method (redirect from Hartree-Fock theory) function. One of these approaches, Møller–Plesset perturbation theory, treats correlation as a perturbation of the Fock operator. Others expand the true multi-electron... 31 KB (4,657 words) - 12:15, 2 April 2024 |