Central Field

Central Field

 

a concept in field theory. A vector field a(P) is called a central field if there exists a point O such that all the vectors a(P) lie on straight lines passing through O and their lengths depend only on the distance r from the point P to O —that is, a(P) = f(r)n, where n is the unit vector of the line. A scalar field u(P) is said to be a central field if there exists a point O such that u(P) depends only on the distance r from the point P to O—that is, u(P) = ϕ(r).

Examples of a central vector field are the force field generated by a point charge and the gravitational force field due to a material particle. An example of a central scalar field is the field of the temperature distribution in an isotropic homogeneous body due to a point source of heat.

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Carex conjuncta Boott; Green-Headed Fox Sedge, Soft Fox Sedge; Central field and woodland edge; Infrequent; C = 6; BSUH 17534.
The 2007 sample did not differ substantially from the 1997 sample in age, diagnosis, visual acuity, the presence of a dense scotoma within the central field, or the presence of a large dense scotoma.
Bill Sargent, Melbourne, Florida Sportsman East Central Field Editor
This is a central field and there is a lot to be shared with people of other faith," said the keynote speaker, a professor of contemporary Islamic studies at the University of Oxford, and a visiting professor at the Faculty of Islamic Studies, Qatar.
Excited dancers from Dinka, Nuer and Shilluk tribes sing and dance in various circles across a central field located a few meters from the main market in Malakal.
The dish pictured here displays characteristic Kraak decoration: a design divided into panels around a central field which often contains birds, animals or flowers.
wide yellow spot near the center of the retina that is responsible for the central field of vision.
The SEL (spectrally enhanced lighting) concept is not based on the proposition that " the eye is more sensitive to bluer wavelengths," or that SEL sources are "more efficacious in the bluer ranges," rather that SEL is an application concerned with lighting at typical interior light levels where the standard definition of peak wavelength for the eye's central field sensitivity remains unchanged from the canonical photopic peak at 555nm.
The macula is a 3-millimeter-wide yellow spot near the center of the retina responsible for the central field of vision.
But because those kicks were a little off, that made it into more of a central field battle, and they won that battle.
Chapters cover the following standard topics: the calculus of variations, Lagrangian mechanics, Hamiltonian mechanics, motion in a central field, collisions and scattering theory, motion in a non-inertial frame, rigid body motion, normal-mode analysis, and continuous Lagrangian systems.
We see our 'green' cars and trucks as an investment in our region and in America's future," said Loretta Vanacore, vice president for Central Field Services.

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