Add bondi.mac

1 files changed, 37 insertions, 0 deletions

diff --git a/bondi.mac b/bondi.mac
new file mode 100644
index 0000000..3577589
--- /dev/null
+++ b/bondi.mac
@@ -0,0 +1,37 @@
+debugmode: true;
+
+linel: 150;
+
+load("ctensor");
+
+dim: 4;
+cframe_flag: false;
+ct_coords: [u, r, theta, phi];
+
+depends([U, V, _beta, _gamma], [u, r, theta]);
+
+lg : zeromatrix(4, 4);
+lg[1, 1] : V * r^-1 * exp(2 * _beta) - U^2 * r^2 * exp(2 * _gamma);
+
+lg[1, 2] : exp(2 * _beta);
+lg[2, 1] : exp(2 * _beta);
+
+lg[1, 3] : U * r^2 * exp(2 * _gamma);
+lg[3, 1] : U * r^2 * exp(2 * _gamma);
+
+lg[3, 3] : - r^2 * exp(2 * _gamma);
+lg[4, 4] : - r^2 * exp(- 2 * _gamma) * sin(theta)^2;
+
+/* Load metric and compute inverse */
+cmetric();
+
+/* For some reason some components must be simplified by hand ... */
+ug[2,2] : expand(ug[2,2]),simp;
+
+/*
+    Calculate Christoffel symbols
+    mcs[i, j, k]: Christoffel symbols of the second kind (one upper index - k)
+*/
+
+christof(false);
+ricci(false);