blob: 519a092b44f5817ca8bef5d2d9856916030e33a1 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
\documentclass{article}
\begin{document}
\title{StaticConformal}
\author{Tom Goodale et al}
\date{April 2002}
\maketitle
\abstract{Base thorn to provide the variables for the static conformal factor}
\section{Purpose}
This thorn provides the variables defining a static conformal factor
which is used to transform the physical metric. If this thorn is
active and the {\bf ADMBase::metric\_type} parameter is set to
`static conformal' then the {\bf ADMBase::g...} variables are the
conformal values as opposed to the physical values.
The transformation is
$$ g_{ij}^{\mbox{physical}} = \psi^4 g_{ij}^{\mbox{conformal}} $$
The extrinsic curvature is not transformed.
Memory is provided for the conformal factor {\bf psi}, its first
derivatives {\bf psix}, {\bf psiy}, {\bf psiz}, and its second
derivatives {\bf psixx}, {\bf psixy}, {\bf psixz}, {\bf psiyy}, {\bf
psiyz}, and {\bf psizz} depending on the setting of the {\bf
conformal\_storage} parameter.
Thorns need to check the value of the grid scalar
{\bf conformal\_state} to determine how many levels of these variables have
actually been calculated.
\begin{itemize}
\item[0]
No conformal factor has been calculated -- thorns may
assume the conformal factor is 1 at all points. (I.e. the metric is physical.)
\item[1]
The conformal factor has been calulated, but no derivatives.
\item[2]
The conformal factor and its first derivatives have been calculated.
\item[3]
The conformal factor and its first and second derivatives have been calculated.
\end{itemize}
\section{Comments}
The {\bf StaticConformal} thorn itself does not calculate any conformal
factor, but does initialise the {\bf conformal\_state} variable to 0.
% Automatically created from the ccl files by using gmake thorndoc
\include{interface}
\include{param}
\include{schedule}
\end{document}
|