This implies that the balancing action of internal contact forces generates a contact force density or Cauchy traction field [1] T ( n , x , t ) {\displaystyle \mathbf {T} (\mathbf {n} ,\mathbf {x} ,t)} that represents a distribution of internal contact forces throughout the volume of the body in a particular configuration of the body at a given time t {\displaystyle t} . It is not a vector field because it depends not only on the position x {\displaystyle \mathbf {x} } of a particular material point, but also on the local orientation of the surface element as defined by its normal vector n {\displaystyle \mathbf {n} } .[9]