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Initial Parameters and Space-times

In order to solve the system we must have 8 initial parameters. Namely, $x^\alpha$ and $\dot{x}^\alpha$. With no loss of generality we will fix $t_0 = 0$ and $\dot{t}$.


\begin{displaymath}
\dot{t}_0 = \sqrt{(1.0+g_{22}{\dot{r}_0}^2+g_{33}{\dot{\theta}_0}^2+g_{44}{\dot{\phi}_0}^2)/(-g_{11})}
\end{displaymath} (6)

where,

\begin{displaymath}
\dot{f}=\frac{df}{d\tau}
\end{displaymath}

The rest may be freely specified. During our experimentation we started at the most obvious place, Schwarzschild. Because of the t independence it greatly simplified things and we were able to test and debug properly. Also, it provided some very nice looking solutions.

Schwarzschild Metric

\begin{displaymath}
ds^2 = -(1-\frac{2m}{r})dt^2 + \frac{1}{1-\frac{2m}{r}}dr^2 + r^2 d\theta^2 + r^2 \sin^2{\theta} d\phi^2
\vspace{1cm}
\end{displaymath} (7)

3-sphere in a 4-dimensional cartesian space
\begin{displaymath}
dl^2 = dr^2 + {R_c}^2 \sin^2\left(\frac{r}{R_c}\right) (d\theta^2 + \sin^2\theta d\phi^2 )
\vspace{1cm}
\end{displaymath} (8)

homogeneous 3-space
\begin{displaymath}
dl^2 = dr^2 + {R_c}^2 \sinh^2\left(\frac{r}{R_c}\right) (d\theta^2 + \sin^2\theta d\phi^2 )
\end{displaymath} (9)



Benjamin Gutierrez 2005-07-24