From 501afaabf8b9291ee78b345ea6e0802ae29bdf68 Mon Sep 17 00:00:00 2001 From: schnetter Date: Mon, 1 Nov 2004 21:48:32 +0000 Subject: For the model "Minkowski/gauge wave": Use the same parameters for the types "expsin" as were already used for "sin". This potentially changes the initial data. Note that the Mexico test uses "sin", which I therefore consider to be authoritative. Complete the documentation. git-svn-id: http://svn.einsteintoolkit.org/cactus/EinsteinInitialData/Exact/trunk@210 e296648e-0e4f-0410-bd07-d597d9acff87 --- doc/documentation.tex | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'doc') diff --git a/doc/documentation.tex b/doc/documentation.tex index 3467456..a10b8db 100644 --- a/doc/documentation.tex +++ b/doc/documentation.tex @@ -533,15 +533,16 @@ The line element is \begin{equation} ds^2=-H dt^2 +Hdx^2+dy^2+dz^2, \end{equation} -where $H=H(x-t)$, for instance $H=1-a*\sin\big((x-t)/d\big)$. +where $H=H(x-t)$, for instance $H=1-a\sin\left((x-t)/\Lambda\right)$. This is flat space but the slice is a planar wave travelling along the x axis. This thorn implements several possible choices for the $H$ function, controlled by the \verb|Minkowski_gauge_wave__what_fn| parameter: \begin{eqnarray} -H(x-t) &=& 1- A \sin \left(\frac{x-t}{d}\right) \\ -H(x-t) &=& \exp \left(A*sin(x)*cos(x)\right) \\ -H(x-t) &=& 1- A exp(-x^2) %%%\\ +H(x-t) &=& 1 - A \sin \left(\frac{x-\omega t}{\Lambda} - \delta\right) \\ +H(x-t) &=& \exp \left(- A \sin \left(\frac{x-\omega t}{\Lambda} + - \delta\right)\right) \\ +H(x-t) &=& 1 - A \exp(-x^2) %%%\\ \end{eqnarray} The parameters are \begin{itemize} @@ -550,10 +551,6 @@ The parameters are \item $\lambda = \verb|Minkowski_gauge_wave__lambda|$, the wavelength \item $\delta = \verb|Minkowski_gauge_wave__phase|$, the phase shift \end{itemize} -Unfortunately, you have to look at the source code to see exactly what -these do. :( -FIXME: someone reverse-engineer the code and change the equations above -to match whatever the code actually does. If the Boolean parameter \verb|Minkowski_gauge_wave__diagonal| is true, then we make the gauge wave travel diagonally across the grid by the -- cgit v1.2.3