Page 153 - Curvature and Homology
P. 153

= (ad(X) Xp, aa) A:
                      = (XP, - e(x) a") AP,
                         P
                      =  (XI A ... A Xp, a1 A ... A - 9(X) ay A ... A ap).
                        Y =l
       It follows that


       that is, O(X) is

       Lemma 4.2.2.
         Indeed,







       Lemma 4.2.3.
         It suffices to verify this formula for forms of  degree 0 and 1 in A(T,*)
       -the  Grassman algebra associated with L. The  identity  is  trivial  for
       forms  of  degree 0 since  they  are  constant  functions. In degree  1 we
       need  only  consider  the forms  ma. Then,  9(XB)wa = CyBawY. But,











       Corollary 4.2.3.   O(X)d = de(X).
       Lemma 4.2.4.   d = &(wa)O(Xa).
         It is  only necessary  to verify  this formula  for the  forms of  degrees
       0 and  1 in A(T,*). Again, since the forms of  degree 0 are the constant
       functions  on  G  both  sides  vanish.  For  a  form  of  Maurer-Cartan  wB
   148   149   150   151   152   153   154   155   156   157   158