SpECTRE
v2024.04.12

The value of the scalar field and its time derivative on element faces forming the worldtube boundary, as well as the Euclidean area element of the face. More...
#include <Tags.hpp>
Public Types  
using  type = std::optional< Variables< tmpl::list< CurvedScalarWave::Tags::Psi, ::Tags::dt< CurvedScalarWave::Tags::Psi >, gr::surfaces::Tags::AreaElement< DataVector > > > > 
The value of the scalar field and its time derivative on element faces forming the worldtube boundary, as well as the Euclidean area element of the face.
If the element does not abut the worldtube, this will be std::nullopt
.