By studying the minimum resources required to perform a unitary
transformation, families of metrics and pseudo-metrics on unitary matrices that
are closely related to a recently reported quantum speed limit by the author
are found. Interestingly, this family of metrics can be naturally converted
into useful indicators of the degree of non-commutativity between two unitary
matrices.Comment: 13 pages in RevTex 4.1, 2 figures, to appear in QIC. This replacement
concentrates only on the more physics and quantum information aspects of the
results reported in the original manuscript with a more detailed proof. The
mathematical results involving the discovery of several matrix inequalities
reported in the original version will be strengthened and rewritten in a
separate postin