define a unit by a such-and-such equation

См. также в других словарях:

• Unit root — In time series models in econometrics, a linear stochastic process has a unit root if 1 is a root of the process s characteristic equation. The process will be non stationary. If the other roots of the characteristic equation lie inside the unit… …   Wikipedia

• Unit circle — In mathematics, a unit circle is a circle with a unit radius, i.e., a circle whose radius is 1. Frequently, especially in trigonometry, the unit circle is the circle of radius 1 centered at the origin (0, 0) in the Cartesian coordinate system in… …   Wikipedia

• Logic and the philosophy of mathematics in the nineteenth century — John Stillwell INTRODUCTION In its history of over two thousand years, mathematics has seldom been disturbed by philosophical disputes. Ever since Plato, who is said to have put the slogan ‘Let no one who is not a geometer enter here’ over the… …   History of philosophy

• Dirac equation — Quantum field theory (Feynman diagram) …   Wikipedia

• Eigenvalue, eigenvector and eigenspace — In mathematics, given a linear transformation, an Audio|De eigenvector.ogg|eigenvector of that linear transformation is a nonzero vector which, when that transformation is applied to it, changes in length, but not direction. For each eigenvector… …   Wikipedia

• Radiative transfer equation and diffusion theory for photon transport in biological tissue — Photon transport in biological tissue can be equivalently modeled numerically with Monte Carlo simulations or analytically by the radiative transfer equation (RTE). However, the RTE is difficult to solve without introducing approximations. A… …   Wikipedia

• Mole (unit) — This article is about physical quantity measurement unit. For other uses, see Mole (disambiguation). The mole is a unit of measurement used in chemistry to express amounts of a chemical substance, defined as an amount of a substance that contains …   Wikipedia

• Comparison of vector algebra and geometric algebra — Vector algebra and geometric algebra are alternative approaches to providing additional algebraic structures on vector spaces, with geometric interpretations, particularly vector fields in multivariable calculus and applications in mathematical… …   Wikipedia

• Eigenvalues and eigenvectors — For more specific information regarding the eigenvalues and eigenvectors of matrices, see Eigendecomposition of a matrix. In this shear mapping the red arrow changes direction but the blue arrow does not. Therefore the blue arrow is an… …   Wikipedia

• Wikipedia:Manual of Style/Dates and numbers — Shortcuts: WP:MOSNUM WP:DATE MOS:NUM This page is part of the Ma …   Wikipedia

• Imaginary unit — i in the complex or cartesian plane; real numbers fall on the horizontal axis, and imaginary numbers fall on the vertical axis In mathematics, the imaginary unit allows the real number system ℝ to be extended to the complex number system ℂ, which …   Wikipedia