SpECTRE
v2024.09.29
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The gradient of the gradient of the lapse. More...
#include <Tags.hpp>
Public Types | |
using | type = tnsr::ij< DataType, Dim, Frame > |
The gradient of the gradient of the lapse.
We define:
\begin{align} \nabla_i \nabla_j \alpha &= \alpha A_i A_j - \alpha \Gamma^k{}_{ij} A_k + \alpha \partial_{(i} A_{j)} \end{align}
where \(\alpha\), \(\Gamma^k{}_{ij}\), \(A_i\), and \(\partial_j A_i\) are the lapse, spatial christoffel symbols of the second kind, the CCZ4 auxiliary variable defined by Ccz4::Tags::FieldA
, and its spatial derivative, respectively.