fourth-order triangulation
31Virus — This article is about the biological agent. For other uses, see Virus (disambiguation). For a generally accessible and less technical introduction to the topic, see Introduction to viruses. Viruses …
32Deutsche Mark — DEM redirects here. For other uses, see DEM (disambiguation). This article is about the Deutsche Mark issued by the Federal Republic of Germany. For the Deutsche Mark issued by the German Democratic Republic, see East German Mark. Deutsche Mark… …
33Spin structure — In differential geometry, a spin structure on an orientable Riemannian manifold allows one to define associated spinor bundles, giving rise to the notion of a spinor in differential geometry. Spin structures have wide applications to mathematical …
34Grand Unified Theory — For the album, see Grand Unification (album). Beyond the Standard Model …
35Leopard tank — Infobox Weapon|is vehicle=yes name=Leopard 1 caption=Leopard 1A3 at the Base Borden Military Museum. type=Main battle tank origin=West Germany length= 9.54/8.29 m (gun forward/rearward) width= 3.37 m height= 2.39/2.70 m (turret roof/absolute)… …
36Islamic calendar — Arabic calendar redirects here. For the Gregorian calendar in Arabic, see Arabic names of calendar months. This …
37Transit of Venus — A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and Earth, obscuring a small portion of the Sun s disk. During a transit, Venus can be seen from Earth as a small black disk moving across the… …
38Angelo Secchi — Angelo Secchi † Catholic Encyclopedia ► Angelo Secchi Astronomer, b. at Reggio in Emilia, Italy, 18 June, 1818; d. 26 Feb., 1878. He was the son of a joiner, Antonio Secchi. His mother (née Luise Belgieri), a practical middle class… …
39Spacetime — For other uses of this term, see Spacetime (disambiguation). Two dimensional analogy of spacetime distortion. Matter changes the geometry of spacetime, this (curved) geometry being interpreted as gravity. White lines do not represent the… …
40Catalan number — For names of numbers in Catalan, see List of numbers in various languages#Occitano Romance. In combinatorial mathematics, the Catalan numbers form a sequence of natural numbers that occur in various counting problems, often involving recursively… …
