about a closed path
31Gauge theory — For a generally accessible and less technical introduction to the topic, see Introduction to gauge theory. In physics, a gauge theory is a type of field theory in which the Lagrangian is invariant under a continuous group of local transformations …
32Traffic Control — ➡ law enforcement * * * Introduction supervision of the movement of people, goods, or vehicles to ensure efficiency and safety. Traffic is the movement of people and goods from one location to another. The movement typically occurs… …
33Polygon — For other uses, see Polygon (disambiguation). Some polygons of different kinds In geometry a polygon (   …
34Umbanda — is an Afro Brazilian religion that blends African religions with Catholicism and Spiritism (Kardecist Spiritualism). Umbanda is related to and has many similitudes with other Afro Brazilian religions like Candomblé, Batuque, Macumba, Quimbanda,… …
35History of perpetual motion machines — The history of perpetual motion machines dates back to the Middle Ages. For millennia, it was not clear whether perpetual motion devices were possible or not, but the development of modern thermodynamics has indicated that they are impossible.… …
36Attitude dynamics and control — The attitude of a body is its orientation as perceived in a certain frame of reference; providing a vector along which a spacecraft is pointing is a description of its attitude. Dynamics is the term for the modeling of changing conditions, due to …
37Magnetism — This article is about magnetic materials. For information about objects and devices that produce a magnetic field, see magnet. For fields that magnets and currents produce, see magnetic field. For other uses, see magnetism (disambiguation).… …
38superconductivity — superconduction /sooh peuhr keuhn duk sheuhn/, n. superconductive /sooh peuhr keuhn duk tiv/, superconducting, adj. superconductor /sooh peuhr keuhn duk teuhr/, n. /sooh peuhr kon deuhk tiv i tee/, n. Physics. the phenomenon of almost perfect… …
39LI-COR Biosciences — [http://www.licor.com LI COR Biosciences] designs, manufactures, and markets integrated instrument systems for plant physiology, biotechnology, environmental research, and drug discovery. LI COR instruments for photosynthesis, gas analysis and… …
40Goathland (Incline Top) railway station — was a short lived, early, railway station in Goathland, North Yorkshire, UK. The actual station was known simply as Goathland but this article is so named to distinguish it from the later Goathland railway station and its article (qv). The… …
