ScalarTensor::sgb::CouplingFunctions::Exponential Class Reference

Coupling function of exponential type. More...

#include <Exponential.hpp>

Classes
struct	Lambda
struct	Gamma

Public Types
using	options = tmpl::list<Lambda, Gamma>

Public Member Functions
	Exponential (double lambda, double gamma)
	Exponential (const Exponential &)=default
Exponential &	operator= (const Exponential &)=default
	Exponential (Exponential &&)=default
Exponential &	operator= (Exponential &&)=default
	Exponential (CkMigrateMessage *m)
	WRAPPED_PUPable_decl_template (Exponential)
void	pup (PUP::er &p) override
double	get_lambda () const
double	get_gamma () const
Public Member Functions inherited from ScalarTensor::sgb::CouplingFunctions::CouplingFunction
	WRAPPED_PUPable_abstract (CouplingFunction)
	CouplingFunction (CkMigrateMessage *m)
void	coupling_function (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const
	Evaluates the coupling function on a scalar field profile, \(F[\Psi]\).
Scalar< DataVector >	coupling_function (const Scalar< DataVector > &scalar_field) const
	Evaluates the coupling function on a scalar field profile, \(F[\Psi]\).
void	coupling_function_prime (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const
	Evaluates the functional derivative of the coupling function, \(\frac{\delta F[\Psi]}{\delta \Psi} \), on a scalar field profile.
Scalar< DataVector >	coupling_function_prime (const Scalar< DataVector > &scalar_field) const
	Evaluates the functional derivative of the coupling function, \(\frac{\delta F[\Psi]}{\delta \Psi} \), on a scalar field profile.
void	coupling_function_prime_prime (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const
	Evaluates the second functional derivative of the coupling function, \(\frac{\delta^2 F[\Psi]}{\delta \Psi^2} \), on a scalar field profile.
Scalar< DataVector >	coupling_function_prime_prime (const Scalar< DataVector > &scalar_field) const
	Evaluates the second functional derivative of the coupling function, \(\frac{\delta^2 F[\Psi]}{\delta \Psi^2} \), on a scalar field profile.

Static Public Attributes
static constexpr Options::String	help

Protected Member Functions
void	coupling_function_impl (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const override
	Specialization of the function that evaluates the coupling function on a scalar field profile.
void	coupling_function_prime_impl (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const override
	Specialization of the function that evaluates the first functional derivative of the coupling function on a scalar field profile.
void	coupling_function_prime_prime_impl (gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > &scalar_field) const override
	Specialization of the function that evaluates the second functional derivative of the coupling function on a scalar field profile.

Detailed Description

Coupling function of exponential type.

Details

The functional form of this coupling is \(F[\Psi] = \lambda e^{\gamma \Psi}\), where both \(\lambda\) and \(\gamma\) are dimensionless.

In the case of exponential coupling the theory does not admit the Kerr metric as a stationary solution, and spontaneous scalarization cannot take place. For this type of coupling the theory is also referred to as Einstein-dilaton-Gauss-Bonnet.

Member Function Documentation

coupling_function_impl()

void ScalarTensor::sgb::CouplingFunctions::Exponential::coupling_function_impl ( gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > & scalar_field ) const

overrideprotectedvirtual

Specialization of the function that evaluates the coupling function on a scalar field profile.

It returns the profile \(F[\Psi] = \lambda e^{- \gamma \Psi}\).

Implements ScalarTensor::sgb::CouplingFunctions::CouplingFunction.

coupling_function_prime_impl()

void ScalarTensor::sgb::CouplingFunctions::Exponential::coupling_function_prime_impl ( gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > & scalar_field ) const

overrideprotectedvirtual

Specialization of the function that evaluates the first functional derivative of the coupling function on a scalar field profile.

It returns the profile \(\frac{\delta F[\Psi]}{\delta \Psi} = - \gamma \lambda e^{- \gamma \Psi}\).

Implements ScalarTensor::sgb::CouplingFunctions::CouplingFunction.

coupling_function_prime_prime_impl()

void ScalarTensor::sgb::CouplingFunctions::Exponential::coupling_function_prime_prime_impl ( gsl::not_null< Scalar< DataVector > * > function_values, const Scalar< DataVector > & scalar_field ) const

overrideprotectedvirtual

Specialization of the function that evaluates the second functional derivative of the coupling function on a scalar field profile.

It returns the profile \(\frac{\delta^2 F[\Psi]}{\delta \Psi^2} = \gamma^2 \lambda e^{- \gamma \Psi}\).

Implements ScalarTensor::sgb::CouplingFunctions::CouplingFunction.

Member Data Documentation

help

Options::String ScalarTensor::sgb::CouplingFunctions::Exponential::help

staticconstexpr

Initial value:

                                  = {
"Coupling function of exponential type"}

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The documentation for this class was generated from the following file:

• src/PointwiseFunctions/ScalarTensor/ScalarGaussBonnet/CouplingFunctions/Exponential.hpp