Scalar field theoryIn theoretical physics, scalar field theory can refer to a relativistically invariant classical or quantum theory of scalar fields. A scalar field is invariant under any Lorentz transformation. The only fundamental scalar quantum field that has been observed in nature is the Higgs field. However, scalar quantum fields feature in the effective field theory descriptions of many physical phenomena. An example is the pion, which is actually a pseudoscalar.
Value theoryIn ethics and the social sciences, value theory involves various approaches that examine how, why, and to what degree humans value things and whether the object or subject of valuing is a person, idea, object, or anything else. Within philosophy, it is also known as ethics or axiology. Traditionally, philosophical investigations in value theory have sought to understand the concept of "the good". Today, some work in value theory has trended more towards empirical sciences, recording what people do value and attempting to understand why they value it in the context of psychology, sociology, and economics.
Instrumental and intrinsic valueIn moral philosophy, instrumental and intrinsic value are the distinction between what is a means to an end and what is as an end in itself. Things are deemed to have instrumental value if they help one achieve a particular end; intrinsic values, by contrast, are understood to be desirable in and of themselves. A tool or appliance, such as a hammer or washing machine, has instrumental value because it helps you pound in a nail or clean your clothes.
