SpECTRE  2021.08.02
RelativisticEuler::Solutions::TovStar< RadialSolution >::RadialVariables< DataType > Struct Template Reference

The radial variables needed to compute the full TOVStar solution. More...

#include <TovStar.hpp>

Public Member Functions

 RadialVariables (DataType radial_coordinate_in)
 

Public Attributes

DataType radial_coordinate {}
 
Scalar< DataType > rest_mass_density {}
 
Scalar< DataType > pressure {}
 
Scalar< DataType > specific_internal_energy {}
 
Scalar< DataType > specific_enthalpy {}
 
DataType dr_pressure {}
 
DataType metric_time_potential {}
 
DataType dr_metric_time_potential {}
 
DataType metric_radial_potential {}
 
DataType dr_metric_radial_potential {}
 
DataType metric_angular_potential {}
 
DataType dr_metric_angular_potential {}
 

Detailed Description

template<typename RadialSolution>
template<typename DataType>
struct RelativisticEuler::Solutions::TovStar< RadialSolution >::RadialVariables< DataType >

The radial variables needed to compute the full TOVStar solution.

RadialSolution must provide a method that fills the radial variables given the equation of state and the Cartesian coordinates \(x^i\)

If the spherically symmetric metric is written as

\[ ds^2 = - e^{2 \Phi_t} dt^2 + e^{2 \Phi_r} dr^2 + e^{2 \Phi_\Omega} r^2 d\Omega^2 \]

where \(r = \delta_{mn} x^m x^n\) is the radial_coordinate and \(\Phi_t\), \(\Phi_r\), and \(\Phi_\Omega\) are respectvely the metric_time_potential, metric_radial_potential, and metric_angular_potential, then the lapse, shift, and spatial metric in the Cartesian coordinates are

\begin{align*} \alpha &= e^{\Phi_t} \\ \beta^i &= 0 \\ \gamma_{ij} &= \delta_{ij} e^{2 \Phi_r} + \delta_{im} \delta_{jn} \frac{x^m x^n}{r^2} \left( e^{2 \Phi_r} - e^{2 \Phi_\Omega} \right) \end{align*}