Borchers algebra 1970-01-01
Borchers algebra refers to a mathematical framework introduced by Daniel Borchers in the context of quantum field theory. It arises notably in the study of algebraic quantum field theory (AQFT), where the focus is on the algebraic structures that underpin quantum fields and their interactions. In Borchers algebra, one typically deals with specific types of algebras constructed from the observables of a quantum field theory. These observables are collections of operators associated with physical measurements.
Favard operator 1970-01-01
The Favard operator is an integral operator used in the field of functional analysis and approximation theory. It is typically associated with the approximation of functions and the study of convergence properties in various function spaces. The operator is used to construct a sequence of polynomials that can approximate continuous functions, particularly in the context of orthogonal polynomials. The Favard operator can be defined in a way that it maps continuous functions to sequences or series of polynomials by integrating against a certain measure.
Fekete–Szegő inequality 1970-01-01
The Fekete–Szegő inequality is a result in complex analysis and functional analysis concerning analytic functions. It is primarily related to bounded analytic functions and their behavior on certain domains, particularly the unit disk.
Fernique's theorem 1970-01-01
Fernique's theorem is a result in probability theory, particularly in the context of Gaussian processes and stochastic analysis. It deals with the continuity properties of stochastic processes, specifically the continuity of sample paths of certain classes of random functions.
Hadamard's method of descent 1970-01-01
Hadamard's method of descent, developed by the French mathematician Jacques Hadamard, is a technique used in the context of complex analysis and number theory, particularly for studying the growth and distribution of solutions to certain problems, such as Diophantine equations and modular forms. The method relies on the concept of reducing a problem in higher dimensions to a problem in lower dimensions (hence the term "descent").
Holomorphic curve 1970-01-01
A holomorphic curve is a mathematical concept from complex analysis and algebraic geometry. Specifically, it refers to a curve that is defined by holomorphic functions. Here’s a breakdown of what this means: 1. **Holomorphic Functions**: A function \( f: U \rightarrow \mathbb{C} \) is called holomorphic if it is complex differentiable at every point in an open subset \( U \) of the complex plane.
William Eccles (physicist) 1970-01-01
William Eccles (1903–1998) was an English physicist known for his contributions to the fields of physics and engineering, particularly in the study of electrical circuits and equipment. He is perhaps best recognized for his work on the development of the concept of the "Eccles-Jordan trigger circuit," which he co-developed with his colleague F. W. Jordan.
Cyclic reduction 1970-01-01
Cyclic reduction is a mathematical and computational technique primarily used for solving certain types of linear systems, particularly those that arise in numerical simulations and finite difference methods for partial differential equations. This method is particularly effective for problems that can be defined on a grid and involve periodic boundary conditions. ### Key Features of Cyclic Reduction: 1. **Matrix Decomposition**: Cyclic reduction typically involves breaking down a large matrix into smaller submatrices.
Denjoy–Luzin–Saks theorem 1970-01-01
The Denjoy–Luzin–Saks theorem is a significant result in the field of real analysis, particularly in the theory of functions and their integrability. The theorem deals with the conditions under which a measurable function can be approximated by simple functions.
Dianalytic manifold 1970-01-01
A **differential manifold** is a mathematical structure that generalizes the concept of curves and surfaces to higher dimensions, allowing for the rigorous study of geometrical and analytical properties in a flexible setting. Each manifold is locally resembling Euclidean space, which means that around each point, the manifold can be modeled in terms of open subsets of \( \mathbb{R}^n \).
Drinfeld reciprocity 1970-01-01
Drinfeld reciprocity is a key concept in the field of arithmetic geometry and number theory, particularly in the study of function fields and their extensions. It is named after Vladimir Drinfeld, who introduced it in the context of his work on modular forms and algebraic structures over function fields. The concept can be viewed as an analogue of classical reciprocity laws in number theory, such as the law of quadratic reciprocity, but applied to function fields instead of number fields.
Drinfeld upper half plane 1970-01-01
The Drinfeld upper half-plane is a mathematical construct that arises in the context of algebraic geometry and number theory, particularly in the study of modular forms and Drinfeld modular forms. It is an analogue of the classical upper half-plane in the theory of classical modular forms but is defined over fields of positive characteristic. ### Definition 1.
Eden growth model 1970-01-01
The Eden growth model, also known as the Eden process or the Eden model, is a concept in statistical physics and mathematical modeling that describes the growth of clusters or patterns in a stochastic (random) manner. It was first introduced by the physicist E. D. Eden in 1961.
Ehrling's lemma 1970-01-01
Ehrling's lemma is a result in functional analysis, particularly in the context of Banach spaces. It is often used to establish properties of linear operators and to analyze the behavior of certain classes of functions or sequences. In the context of Banach spaces, Ehrling's lemma provides conditions under which a bounded linear operator can be approximated in some sense by a sequence of simpler operators.
Enveloping von Neumann algebra 1970-01-01
An enveloping von Neumann algebra is a concept from the field of functional analysis, specifically in the context of operator algebras. To understand this concept, we first need to clarify what a von Neumann algebra is. A **von Neumann algebra** is a *-subalgebra of bounded operators on a Hilbert space that is closed in the weak operator topology and contains the identity operator.
Euler–Poisson–Darboux equation 1970-01-01
The Euler–Poisson–Darboux equation is a second-order linear partial differential equation that arises in various contexts in mathematical physics and engineering. It can be seen as a generalization of the heat equation and is particularly useful in the study of problems involving wave propagation and diffusion.
Jackson's inequality 1970-01-01
Jackson's inequality is a result in approximation theory, particularly in the context of polynomial approximation of continuous functions. It provides a way to estimate the best possible approximation of a continuous function using a sequence of polynomial functions.
Khinchin's theorem, a fundamental result in probability theory, pertains to the factorization of certain types of distributions, specifically those that possess a "stable" structure. While there are several results attributed to the mathematician Aleksandr Khinchin, one crucial aspect relates to the factorization of distributions in the context of characteristic functions.
William Spottiswoode 1970-01-01
William Spottiswoode (1825–1883) was a notable British mathematician, astronomer, and physicist known for his work in various scientific fields, particularly in optics and astronomy. He made significant contributions to mathematical physics and was involved in the development of new instruments for astronomical observations. Spottiswoode was also an active member of scientific societies and served as the President of the Royal Society from 1878 until his death in 1883.
Cagniard–De Hoop method 1970-01-01
The Cagniard–De Hoop method is a mathematical technique used in seismology and acoustics for solving wave propagation problems, particularly in the context of wave equations. It is especially useful for analyzing wavefields generated by a point source in a medium.