Hayashi trackThe Hayashi track is a luminosity–temperature relationship obeyed by infant stars of less than in the pre-main-sequence phase (PMS phase) of stellar evolution. It is named after Japanese astrophysicist Chushiro Hayashi. On the Hertzsprung–Russell diagram, which plots luminosity against temperature, the track is a nearly vertical curve. After a protostar ends its phase of rapid contraction and becomes a T Tauri star, it is extremely luminous. The star continues to contract, but much more slowly.
Space tetherSpace tethers are long cables which can be used for propulsion, momentum exchange, stabilization and attitude control, or maintaining the relative positions of the components of a large dispersed satellite/spacecraft sensor system. Depending on the mission objectives and altitude, spaceflight using this form of spacecraft propulsion is theorized to be significantly less expensive than spaceflight using rocket engines. Tether satellites might be used for various purposes, including research into tether propulsion, tidal stabilization and orbital plasma dynamics.
Economic rentIn neoclassical economics, economic rent is any payment (in the context of a market transaction) to the owner of a factor of production in excess of the cost needed to bring that factor into production. In classical economics, economic rent is any payment made (including imputed value) or benefit received for non-produced inputs such as location (land) and for assets formed by creating official privilege over natural opportunities (e.g., patents).
Heterodox economicsHeterodox economics is any economic thought or theory that contrasts with orthodox schools of economic thought, or that may be beyond neoclassical economics. These include institutional, evolutionary, feminist, social, post-Keynesian (not to be confused with New Keynesian), ecological, Austrian, complexity, Marxian, socialist, and anarchist economics. Economics may be called orthodox or conventional economics by its critics.
