Divergence

(redirected from divergences)
Also found in: Dictionary, Thesaurus, Medical, Financial.

divergence

[də′vər·jəns]
(electronics)
The spreading of a cathode-ray stream due to repulsion of like charges (electrons).
(fluid mechanics)
The ratio of the area of any section of fluid emerging from a nozzle to the area of the throat of the nozzle.
(mathematics)
For a vector-valued function, the sum of the diagonal entries of the Jacobian matrix; it is the scalar product of the del operator and the vector.
(meteorology)
The two-dimensional horizontal divergence of the velocity field.
(nucleonics)
In a nuclear reactor, the condition wherein the number of neutrons produced increases in each succeeding generation.
(oceanography)
A horizontal flow of water, in different directions, from a common center or zone.
(physics)
The spreading apart of a beam of particles of light.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Divergence

 

in biology, the divergence of characters of organisms in the process of evolution.

The concept of divergence was proposed by C. Darwin to explain the appearance of diverse varieties of cultivated plants, breeds of domestic animals, and biological species in nature. In artificial selection divergence within each group of cultivated plants and domestic animals depends on the needs of man. Darwin used the principle of divergence to explain species formation in nature. If a species has a broad distribution and adapts to various ecological conditions, divergence takes place. Divergence is expressed in the appearance of differences in populations that were originally similar and is caused by the inevitably slightly different direction of natural selection in various parts of a species’ range. Divergence leads to the appearance of organisms that vary in structure and function; this in turn assures more complete use of environmental conditions, since, according to Darwin, the greatest “sum of life” is realized by the broadest variety of structures. Divergence is supported by the struggle for existence: usually even slightly specialized forms have selective advantages, which brings about more rapid extinction of intermediate forms and development of various types of isolation. The principle of divergence also explains the process of formation of larger (supraspecies) systematic groups and the rise of gaps between them.

A. V. IABLOKOV


Divergence

 

[of a vector field a(M) at a point (x, y, z)], the scalar quantity

div a = σPx + σQy + σRR/σZ

where P, Q, and R are components of the vector a. The divergence is the limit of the ratio of the flux of a vector field through a closed surface surrounding the given point, to the volume delimited by it when the surface contracts toward the point. Divergence plays an important role in the applications of mathematics to physics. For example, if the vector field a(M) is considered to be a velocity field in a steady flow of an incompressible fluid, then div a at a point designates the intensity of the source (div a > 0) or of the flow (div a < 0) located at this point, or the absence of source and flow (div a = 0). The properties of divergence are:

div (a + b) = div a + div b

div (φa) = φ div a + a grad φ div rot a =0

div grad φ = Δφ

where Δ is a Laplace operator.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

divergence

divergenceclick for a larger image
Directional divergence or divergence due to diffluent flow.
i. A static instability due to the aerodynamic loads which deform the control surface or body being greater than the elastic restoring forces.
ii. A situation in which a control application by the pilot results in uncommanded and/or undesirable behavior of the aircraft that is unintended by the pilot, such as a steepening spiral descent, spin, pitch-up, etc. Divergence may result in severe deformation or even breakup of the aircraft.
iii. A condition that exists when the distribution of winds within a given area results in a net horizontal flow of air outward from the region.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved

digital divergence

(1) See technology gap.

(2) Using digital technologies, the capability of creating infinite product variations that were far more difficult by mechanical methods. See Long Tail and digital convergence.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
It is believed that the move will provide banks with a little more leeway in dealing with the apex bank's mandatory divergence rules.
Spiders, DNA barcode, genetic distance, divergence.
It's conceivable that English could fracture into two languages some day, particularly if the divergence were to be driven by a political wedge.
In this section, we give two examples for calculating the divergences A(P, Q), h(P, Q), [J.sub.R](Q, P), K(Q, P), and [[chi].sup.4](P, Q) and verify inequalities (14), (22), (48), and (56) or verify bounds of [[chi].sup.4](P,Q).
In silico analysis also provides a clue for diverse functions of maize BAG genes in various biological processes because of the presence of diverse structures and functional divergences.
L'Assemblee constituante a commence le reexamen des articles de divergence ayant souleve un large tolle au niveau des comites, alors qu'ils etaient en cours de discussions.
Key Words: Evolution; phylogenetics; tree thinking; estimating species divergence times; software.
- Divergence is simply noting the difference on the chart between the direction that the Stochastics is moving when compared to how price action has been moving.<br> - When the two are moving in opposite directions, divergence is present.<br> - George Lane, the creator of Stochastics believed that Stochastic divergence is the most powerful signal given.<br> - Two types of divergences; positive and negative
Bregman divergences have recently received a great deal of interest recently in terms of clustering and finding unsupervised projections of a data set [2, 5, 4, 3, 1].
Liese and Vajda [15] have introduced a systematic theory of these divergences.