A miracle in trace: Too good to be true! But it is truly true

摘要

Trace is an invariant of censorial transformation. Figure 1 shows examples of trace. There are many other invariants, but trace is unique in that it has a physical meaning that can guide composites design and testing. It remains the same regardless if the laminate is stretched or twisted, or symmetric or unsymmetric. No other property of composites is so unifying and universal. It is truly a miracle.