Another object of this type gives the flux of the 4-momentum, and is symmetric with rank 2, like the moment of inertia type of this object.
A multilinear map from any space has a corresponding unique linear map from the corresponding space containing these objects, by a universal property. The force per unit volume from a charge distribution equals the difference between the divergence of one of these objects and time-derivative of the Poynting vector, and that example is named for Maxwell. When these objects are composed of both (*) vectors and covectors, they have contravariant and covariant orders, represented by lowered and raised indices. Another object of this type gives the flux of the 4-momentum, and is symmetric with rank 2, like the moment of inertia type of this object. For 10 points, name these objects often described as multidimensional arrays.
A multilinear map from any space has a corresponding unique linear map from the corresponding space containing these objects, by a universal property.
tensors [or tensor product; or stress tensor]