Skalärt

Skalärt is a term used in some Nordic-language mathematical and physical literature to denote a quantity that has magnitude but no direction. In this sense, skalärt is equivalent to the standard mathematical notion of a scalar, and it is related to the adjective skalär used in Swedish and Norwegian to describe such quantities. Scalar quantities are invariant under coordinate transformations; rotating or translating the reference frame does not change their value.

A scalar can be a single real or complex number, or, more generally, the value assigned by a scalar field to points in space. Examples include temperature, mass, and energy. A scalar field assigns a single value to every point in a region.

In contrast to vectors and tensors, scalars carry no directional information. The magnitude of a vector is a scalar, and operations such as the dot product yield scalar results. Scalars are closed under addition, subtraction, and multiplication, and multiplying a scalar by a real or complex number yields another scalar.

Usage notes: While scalar concepts are standard across mathematics and physics, the term skalärt appears primarily in Nordic-language sources. In English, the term scalar is used consistently; in Nordic texts the related word skalär (adjective) or skalärt (inflected form) may be encountered depending on grammar.

See also: scalar, scalar field, vector, tensor, invariance.