pure rotational motion
81Geometric algebra — In mathematical physics, a geometric algebra is a multilinear algebra described technically as a Clifford algebra over a real vector space equipped with a non degenerate quadratic form. Informally, a geometric algebra is a Clifford algebra that… …
82Callisto (moon) — Callisto View of the heavily cratered terrain of Callisto s anti Jovian hemisphere obtained in 2001 by NASA s Galileo spacecraft. The large impact structure Asgard is on the limb at upper right. The prominent rayed crater below and just right of… …
83Blowback (arms) — Blowback is an operating system for autoloading firearms that utilizes energy created by combustion in the chamber and bore acting directly on the bolt face through the cartridge. Other operating systems are recoil operation, gas operation,… …
84nature, philosophy of — Introduction the discipline that investigates substantive issues regarding the actual features of nature as a reality. The discussion here is divided into two parts: the philosophy of physics and the philosophy of biology. In this… …
85Spin-statistics theorem — Statistical mechanics Thermodynamics · …
86Linkage (mechanical) — This article is about assemblies of links designed to manage forces and movement. For other uses, see Linkage. Variable stroke engine (Autocar Handbook, Ninth edition) A mechanical linkage is an assembly of bodies connected together to manage… …
87Ganymede (moon) — Ganymede Image of Ganymede s anti Jovian hemisphere taken by the Galileo probe. Lighter surfaces, such as in recent impacts, grooved terrain and the whitish north polar cap at upper right, are enriched in water ice. Discovery …
88technology, history of — Introduction the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …
89Knuckleball — A knuckleball (or knuckler for short) is a baseball pitch with an erratic, unpredictable motion. The pitch is thrown so as to minimize the spin of the ball in flight. This causes vortices over the stitched seams of the baseball during its… …
90Crystal structure — In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice… …
