00001 subroutine kerr_schild_transverse_part(x,y,z,dgamma)
00002 use phys_constant, only : long
00003 use def_bh_parameter, only : m_kerr
00004 implicit none
00005 real(long) :: dgamma(3)
00006 real(long) :: x, y, z, r, lvu(0:3), lvd(0:3), H, gradH(3)
00007 real(long) :: Hp1, Hp1m23, H3H1, san, lvugradH, m, H2m
00008
00009 san = 1.0d0/3.0d0
00010 call kerr_schild_r_lv_home(x,y,z,r,lvu,lvd,H)
00011 call kerr_schild_gradH(x,y,z,r,H,gradH)
00012 m = m_kerr ; H2m = H**2/m
00013 Hp1 = 1.0d0 + H
00014 Hp1m23 = Hp1**(-2.0d0/3.0d0)
00015 H3H1 =(3.0d0 + H)/Hp1
00016 lvugradH = lvu(1)*gradH(1)+lvu(2)*gradH(2)+lvu(3)*gradH(3)
00017
00018 dgamma(1:3) = san*Hp1m23*(gradH(1:3) - H3H1*lvugradH*lvu(1:3)) &
00019 & - H2m*Hp1m23*lvu(1:3)
00020
00021 end subroutine kerr_schild_transverse_part
