Lighting a particular area, and falls within a given solid angle. The SI unit for luminance is candela per square metre (cd/m). The CGS unit of luminance is the stilb, which is equal to one candela per square centimetre or 10 kcd/m. The amount of useful light emitted from a source or the luminous flux is measured in lumen (lm). The SI unit of illuminance and luminous emittance, being the luminous power per area, is measured in Lux. It is used in photometry as a measure of the intensity, as perceived by the human eye, of light that hits or passes
Pushforward measure Pushforward measure In measure theory, a discipline within mathematics, a pushforward measure (also push forward, push-forward or image measure) is obtained by transferring ("pushing forward") a measure from one measurable space to another using a measurable function. Given measurable spaces formula_1 and formula_2, a measurable mapping formula_3 and a measure formula_4, the pushforward of formula_5 is defined to be the measure formula_6 given by This definition applies "mutatis mutandis" for a signed or complex measure. The pushforward measure is also denoted as formula_9, formula_10, or formula_11. Theorem: A measurable function "g" on "X" is integrable with respect to the pushforward