inertial interval
51Solstice — For other uses, see Solstice (disambiguation). UTC date and time of solstices and equinoxes[1] year Equinox Mar Solstice June Equinox Sept Solstice Dec day time day time day time day time 2004 20 …
52Time travel — This article details time travel itself. For other uses, see Time Traveler. Time travel is the concept of moving between different moments in time in a manner analogous to moving between different points in space, either sending objects (or in… …
53Geodesic — [ great circle arcs.] In mathematics, a geodesic IPA|/ˌdʒiəˈdɛsɪk, ˈdisɪk/ [jee uh des ik, dee sik] is a generalization of the notion of a straight line to curved spaces . In presence of a metric, geodesics are defined to be (locally) the… …
54Dead reckoning — For other uses, see Dead reckoning (disambiguation). The navigator plots his 9am position, indicated by the triangle, and, using his course and speed, estimates his position at 9:30am and 10am. In navigation, dead reckoning (also ded (for… …
55Desmodromic valve — In general mechanical terms, the word desmodromic is used to refer to mechanisms that have different controls for their actuation in different directions. Desmodromic poppet valve in Ducati engine. A desmodromic valve is a reciprocating engine… …
56Philosophy of space and time — is the branch of philosophy concerned with the issues surrounding the ontology, epistemology, and character of space and time. While such ideas have been central to philosophy from its inception, the philosophy of space and time was both an… …
57Bohr–Einstein debates — The Bohr–Einstein debates is a popular name given to what was actually a series of epistemological challenges presented by Albert Einstein against what has come to be called the standard or Copenhagen interpretation of quantum mechanics. Since… …
58Reynolds number — In fluid mechanics and heat transfer, the Reynolds number mathrm{Re} is a dimensionless number that gives a measure of the ratio of inertial forces ({old mathrm V} ho) to viscous forces (mu / L) and, consequently, it quantifies the relative… …
59Minkowski diagram — In the theory of relativity each observer assigns the event at A to a different time and location. The Minkowski diagram was developed in 1908 by Hermann Minkowski and provides an illustration of the properties of space and time in the special… …
60surveying — /seuhr vay ing/, n. 1. the science or scientific method of making surveys of land. 2. the occupation of one who makes land surveys. 3. the act of one who surveys: The surveying required nearly two days. [1425 75; late ME: act of examining… …
