Generalized function whose value is zero everywhere except at zero
"Delta function" redirects here. For other uses, see Delta function (disambiguation).
Differential equations
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List of named differential equations
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People
List
Isaac Newton
Gottfried Leibniz
Jacob Bernoulli
Leonhard Euler
Józef Maria Hoene-Wroński
Joseph Fourier
Augustin-Louis Cauchy
George Green
Carl David Tolmé Runge
Martin Kutta
Rudolf Lipschitz
Ernst Lindelöf
Émile Picard
Phyllis Nicolson
John Crank
v
t
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In mathematical analysis, the Dirac delta function (or δ distribution), also known as the unit impulse,[1] is a generalized function on the real numbers, whose value is zero everywhere except at zero, and whose integral over the entire real line is equal to one.[2][3][4] Since there is no function having this property, to model the delta "function" rigorously involves the use of limits or, as is common in mathematics, measure theory and the theory of distributions.
The delta function was introduced by physicist Paul Dirac, and has since been applied routinely in physics and engineering to model point masses and instantaneous impulses. It is called the delta function because it is a continuous analogue of the Kronecker delta function, which is usually defined on a discrete domain and takes values 0 and 1. The mathematical rigor of the delta function was disputed until Laurent Schwartz developed the theory of distributions, where it is defined as a linear form acting on functions.
^atis 2013, unit impulse.
^Arfken & Weber 2000, p. 84.
^Dirac 1930, §22 The δ function.
^Gelfand & Shilov 1966–1968, Volume I, §1.1.
and 24 Related for: Dirac delta function information
mathematical analysis, the Diracdeltafunction (or δ distribution), also known as the unit impulse, is a generalized function on the real numbers, whose...
}\delta (t-kT)} for some given period T {\displaystyle T} . Here t is a real variable and the sum extends over all integers k. The Diracdeltafunction...
function is often confused for both the Kronecker deltafunction and the unit sample function. The Diracdelta is defined as: { ∫ − ε + ε δ ( t ) d t = 1 ∀...
of formalizing the idea of the Diracdeltafunction, an important tool in physics and other technical fields. A Dirac measure is a measure δx on a set...
ramp function: H ( x ) := d d x max { x , 0 } for x ≠ 0 {\displaystyle H(x):={\frac {d}{dx}}\max\{x,0\}\quad {\mbox{for }}x\neq 0} The Diracdelta function...
function contains all frequencies (see the Fourier transform of the Diracdeltafunction, showing infinite frequency bandwidth that the Diracdelta function...
quantum mechanics the delta potential is a potential well mathematically described by the Diracdeltafunction - a generalized function. Qualitatively, it...
{\displaystyle \delta (t)} is δ ( f ) = 1 , {\displaystyle \delta (f)=1,} means that the frequency spectrum of the Diracdeltafunction is infinitely broad...
in distribution theory, the derivative of the signum function is two times the Diracdeltafunction, which can be demonstrated using the identity sgn ...
of the Diracdeltafunction to higher dimensions, and is non-zero only on the surface of D. It can be viewed as the surface delta prime function. It is...
relatively simple applications use the Diracdeltafunction, which can be treated formally as if it were a function, but the justification requires a mathematically...
potentials that are not functions but are distributions, such as the Diracdeltafunction. It is easy to visualize a sequence of functions meeting the requirement...
the probability density function of X {\displaystyle X} and δ ( ⋅ ) {\displaystyle \delta (\cdot )} be the Diracdeltafunction. It is possible to use...
career, Dirac made numerous important contributions to mathematical subjects, including the Diracdeltafunction, Dirac algebra and the Dirac operator...
further steps were taken, basic to future work. The Diracdeltafunction was boldly defined by Paul Dirac (an aspect of his scientific formalism); this was...
distribution of a function Difference operator (Δ) Diracdeltafunction (δ function) Kronecker delta ( δ i j {\displaystyle \delta _{ij}} ) Laplace operator...
introduction of several component wave functions in Pauli's phenomenological theory of spin. The wave functions in the Dirac theory are vectors of four complex...
the step response to a step input, or the impulse response to a Diracdeltafunction input. In the frequency domain (for example, looking at the Fourier...
continuity in his Cours d'Analyse, and in defining an early form of a Diracdeltafunction. As Cantor and Dedekind were developing more abstract versions of...
Heaviside step function is equal to the Diracdeltafunction, i.e. d H ( x ) d x = δ ( x ) {\displaystyle {\frac {dH(x)}{dx}}=\delta (x)} and similarly...
{\displaystyle x} is the Diracdelta (function) distribution centered at the position x {\displaystyle x} , often denoted by δ x {\displaystyle \delta _{x}} . In quantum...
variance as a generalized function; specifically, as a Diracdeltafunction δ {\displaystyle \delta } translated by the mean μ {\displaystyle \mu } , that...