regular commutator
11Representation theory — This article is about the theory of representations of algebraic structures by linear transformations and matrices. For the more general notion of representations throughout mathematics, see representation (mathematics). Representation theory is… …
12Electric generator — U.S. NRC image of a modern steam turbine generator In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge (usually carried by electrons) to flow… …
13Magneto (generator) — 2kW Société de l Alliance magneto generator for arc lamps, of around 1870 This article is about magnetos as electrical generators. For other electrical uses, see Magneto. A magneto is an electrical generator that uses permanent magnets to produce …
14Coxeter group — In mathematics, a Coxeter group, named after H.S.M. Coxeter, is an abstract group that admits a formal description in terms of mirror symmetries. Indeed, the finite Coxeter groups are precisely the finite Euclidean reflection groups; the symmetry …
15Congruence lattice problem — In mathematics, the congruence lattice problem asks whether every algebraic distributive lattice is isomorphic to the congruence lattice of some other lattice. The problem was posed by Robert P. Dilworth, and for many years it was one of the most …
16Time in physics — In physics, the treatment of time is a central issue. It has been treated as a question of geometry. One can measure time and treat it as a geometrical dimension, such as length, and perform mathematical operations on it. It is a scalar quantity… …
17Telegraphy — (from the Greek words (τηλε) = far and (γραφειν) = write) is the long distance transmission of written messages without physical transport of letters. Radiotelegraphy or wireless telegraphy transmits messages using radio. Telegraphy includes… …
18Color television — Title card for NBC, promoting their broadcast in RCA color . Color television is part of the history of television, the technology of television and practices associated with television s transmission of moving images in color video. In its most… …
19Frobenius theorem (differential topology) — In mathematics, Frobenius theorem gives necessary and sufficient conditions for finding a maximal set of independent solutions of an overdetermined system of first order homogeneous linear partial differential equations. In modern geometric terms …
20Timeline of radio — The timeline of radio lists within the history of radio, the technology and events that produced instruments that use radio waves and activities that people undertook. Later, the history is dominated by programming and contents, which is closer… …
