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+C Milne spacetime metric ?!?!?
+C Suggested by Matteo Rossi and E. Onofri (Univ. di Parma, Italy)
+C They inted to use thsi metric for simulating an Pre-Big-Bang
+C Cosmology, as proposed by Veneziano some year ago 
+C
+C Author : D. Vulcanov (Timsoara, Romania)
+C see ../../README for copyright & licensing info
+C
+C $Header$
+
+#include "cctk.h"
+
+      subroutine Exact__Milne(
+     $     x, y, z, t,
+     $     gdtt, gdtx, gdty, gdtz, 
+     $     gdxx, gdyy, gdzz, gdxy, gdyz, gdzx,
+     $     gutt, gutx, guty, gutz, 
+     $     guxx, guyy, guzz, guxy, guyz, guzx,
+     $     psi, Tmunu_flag)
+
+      implicit none
+
+c input arguments
+      CCTK_REAL x, y, z, t
+
+c output arguments
+      CCTK_REAL gdtt, gdtx, gdty, gdtz, 
+     $       gdxx, gdyy, gdzz, gdxy, gdyz, gdzx,
+     $       gutt, gutx, guty, gutz, 
+     $       guxx, guyy, guzz, guxy, guyz, guzx
+      CCTK_DECLARE(CCTK_REAL, psi,)
+      LOGICAL   Tmunu_flag
+
+c local variables
+      CCTK_REAL coef, x2,y2,z2,t2
+
+C This is a vacuum spacetime with no cosmological constant
+      Tmunu_flag = .false.
+
+      x2= x*x
+      y2= y*y
+      z2= z*z
+      t2= t*t
+      coef= t2/(1.d0+ x2 +y2+ z2)
+
+      gdtt = -1.d0 
+      gdtx = 0.d0  
+      gdty = 0.d0 
+      gdtz = 0.d0 
+      gdxx =  coef*(1.d0+y2+z2) 
+      gdyy =  coef*(1.d0+x2+z2) 
+      gdzz =  coef*(1.d0+x2+y2)
+      gdxy = -coef*x*y 
+      gdyz = -coef*y*z 
+      gdzx = -coef*x*z
+
+      gutt = -1.d0 
+      gutx = 0.d0 
+      guty = 0.d0 
+      gutz = 0.d0 
+      guxx = (1.d0+x2)/(t2)
+      guyy = (1.d0+y2)/(t2)
+      guzz = (1.d0+z2)/(t2)
+      guxy = x*y/(t2)
+      guyz = y*z/(t2) 
+      guzx = x*z/(t2)
+
+
+      return
+      end