codzienność: Unobtainium

Evidence: 100 • authority: 72

Unobtainium (or unobtanium) is a term used in fiction, engineering, and common situations for a material ideal for a particular application but impractically difficult or impossible to obtain. Unobtainium originally referred to materials that do not exist at all, but can also be used to describe real materials that are unavailable due to extreme rarity or cost. It can also be used to refer to a device rather than a material. The properties of any particular example of unobtainium depend on the intended use. For example, a pulley made of unobtainium might be massless and frictionless. But for a nuclear rocket, unobtainium might have the needed qualities of lightness, strength at high tempera…

Evidence: 48 • authority: 88

A T-matrix approach to describe them all: materials, metamaterials, and metasurfaces. A T-matrix, also called transition matrix, expresses how an object converts an incident into a scattered field. The object can be classical, like a traditional scatterer for which the T-matrix can be obtained from Maxwell’s equations, or a molecule, which prompts a quantum-chemical treatment to capture its T-matrix. When combined with a renormalization of the T-matrix upon periodically arranging the object, many properties can be analytically expressed. Examples of such properties aee effective material parameters or expressions of how a metasurface diffracts light. Both can be used to design optical mater…

Evidence: 36 • authority: 80

How smart home materials can shield us from extreme heat and cut energy bills all year