Equation Icon  ab mn 2 ab an bm 1- ab mt nc /\ = - h @mnh + @mh @nh + 2 g gmn@ch @t h am bt nc bm at nc ct am bn - g gnt@ch @mh - g gnt@ch @mh + gmng @ch @th 1- am bn ab mn cp te + 8(2g g - g g )(2gctgep - gtegcp)@mh @nh . (15)