268 Antisymmetry

A property of a mapping under which swapping two inputs multiplies the output value by minus one that is used to build determinants of matrices.

definition [d] (Antisymmetry) A property of a tensor or matrix where its components change sign when their indices are interchanged, satisfying the following conditions:

  • (Tensor Component Form) For a second-rank tensor \(A\), it is antisymmetric if \(A_{mn} = -A_{nm}\) for all \(m\) and \(n\).
  • (Diagonal Property) For any antisymmetric matrix, the diagonal elements (where \(m=n\)) must be zero.
  • (Dual Association) In 3-D space, every antisymmetric second-rank tensor \(C\) can be associated with a dual pseudovector \(\mathbf{C}\).

where

  • \(A\) is a tensor
  • \(m, n\) are indices identifying components
  • \(C\) is an antisymmetric tensor