Page 235 - Curvature and Homology
P. 235

In terms of  the  metric g, the connection  defined in § 5.3 is given by the
       coefficients







       Differentiating  with  respect  to  5'  we  conclude  that  Rf,,.  = 0.

       Theorem 6.7.3.   A complex parallelisable manifold has a natural hermitian
       metric of  zero curvature.
         Since




       (Dj denoting  covariant  differentiation  with  respect  to  the  given  con-
       nection), it follows that



       Multiplying these equations by I;, and taking account of  the relations



       we conclude that
                            Dj 5':)  = 0,  Y  = 1, -*,  n.

       Thus, we  have

       Corollary.  A  complex  parallelisable  manifold  has  a  natural  hermitian
       metric with respect to which the given field  of frames  is parallel.
         The results of  this section are interpreted in V1.G.



                6.8.  Compact complex  parallelisable manifolds
         Let  M  be  a  compact  complex  parallelisable  manifold.  Since  the
       curvature of  M  (defined  by  the connection  (6.7.1))  vanishes,  the con-
       nection is holomorphic; hence, so is the torsion, that is, in the notation
       of  5 5.3
                            d"D =0,  i=  1;-,n
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