Mathematical Background Concept of linear Invariants For 3x3 matrix a defined in a certain coordinate frame Vector vect(A)≡a≡言a13-a 21-12 Trace tr(A)三a11+a22+a33 Properties vect(a)=0 if a is symmetric tr(a)=0 if A is skew-symmetric vect(ab)=-axb tr(ab)=abMathematical Background • Concept of Linear Invariants For 3x3 matrix A defined in a certain coordinate frame: Properties vect(A) = 0 if A is symmetric tr(A) = 0 if A is skew-symmetric Vector Trace