Mathematical Background Linear Invariant of a rotation matrix(cont'd) 士√1-G+省+嗡) sin=+llls e=qsin p lall +(1-9 Q aq xx) Q=o1+⊥qq ox Sign problem Whenφ=π, Q is not uniquely definedMathematical Background • Linear Invariant of a rotation matrix (cont'd) Sign Problem When  = , Q is not uniquely defined