null gravity
61Experiment — Experimental redirects here. For the musical classification, see Experimental music. For other uses, see Experiment (disambiguation). Even very young children perform rudimentary experiments in order to learn about the world. An experiment is a… …
62Metric signature — The signature of a metric tensor (or more generally a nondegenerate symmetric bilinear form, thought of as quadratic form) is the number of positive and negative eigenvalues of the metric. That is, the corresponding real symmetric matrix is… …
63Killing horizon — A Killing horizon is a null hypersurface on which there is a null Killing vector field.Associated to a Killing horizon is a geometrical quantity known as surface gravity, kappa. If the surface gravity vanishes, then the Killing horizon is said to …
64Geodesic (general relativity) — This article is about the use of geodesics in general relativity. For the general concept in geometry, see geodesic. General relativity Introduction Mathematical formulation Resources …
65Goldberg-Sachs theorem — The Goldberg Sachs theorem is a result in Einstein s theory of general relativity about vacuum solutions of the Einstein field equations relating the existence of a certain type of congruence with algebraic properties of the Weyl tensor. More… …
66Russia — /rush euh/, n. 1. Also called Russian Empire. Russian, Rossiya. a former empire in E Europe and N and W Asia: overthrown by the Russian Revolution 1917. Cap.: St. Petersburg (1703 1917). 2. See Union of Soviet Socialist Republics. 3. See Russian… …
67eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …
68England (Before the Reformation) — England (Before the Reformation) † Catholic Encyclopedia ► England (Before the Reformation) This term England is here restricted to one constituent, the largest and most populous, of the United Kingdom of Great Britain and Ireland.… …
69List of ReBoot characters — This is a list of characters from the animated television series, ReBoot. With the exception of a few characters, such as Bob, most ReBoot characters are named after technical computer terms or pieces of computer hardware.[verification needed]… …
70Chaotic Inflation theory — Physical cosmology Universe · Big Bang …
