Instances of this class can be given to mty::Model when launching a calculation to customize the output. More...

#include <feynOptions.h>

Public Types
using	LagrangianFilter = std::function< bool(mty::InteractionTerm const &)>
	Type definition for a Lagrangian filter. More...

using	DiagramFilter = std::function< bool(mty::FeynmanDiagram const &)>
	Type definition for a Feynman diagram. More...

Public Member Functions
	FeynOptions ()
	Default constructor, only constructor of this class (expect copy and move). More...

bool	getFeynRuleCalculation () const

int	getLoopOrder () const

int	getExpansionOrder () const

int	getTopology () const

std::vector< int > const &	getFermionOrder () const

std::vector< LagrangianFilter > const &	getLagrangianFilters () const

std::vector< DiagramFilter > const &	getDiagramFilters () const

csl::Expr	getWilsonOperatorCoefficient () const

OperatorBasis	getWilsonOperatorBasis () const

void	setFeynmanRuleMode ()
	Sets the value of feynRuleCalculation to true (the default value of this member is false). More...

void	setLoopOrder (int t_nLoops, int nExternalLegs)
	Sets the number of loops for the calculation. More...

void	setTopology (int t_topology)
	Sets the topology for the calculation. More...

void	setFermionOrder (std::vector< int > const &order)
	Sets the fermion order used to express the amplitude. More...

void	setWilsonOperatorCoefficient (csl::Expr const &factor)
	Sets the Wilson operator coefficient wilsonOperatorCoefficient. More...

bool	passFilters (FeynmanDiagram const &diagram) const
	Tells if a diagram passes all diagram filters. More...

void	applyFilters (std::vector< Lagrangian::TermType > &lagrangian) const
	Applies the Lagrangian filters on a vector of vertices. More...

std::vector< FeynmanRule const * >	applyFilters (std::vector< FeynmanRule > const &lagrangian) const
	Filters a set a Feynman rules using the lagrangian filters. More...

void	applyFilters (std::vector< FeynmanDiagram > &diagrams, bool forceFilters=false) const
	Applies the diagram filters on a vector of Feynman diagrams. More...

template<class Filter >
void	addFilter (Filter &&filter)
	Adds one filter (LagrangianFilter or DiagramFilter) to the options. More...

void	addFilters ()
	Overloads to add 0 filter (this function does nothing). More...

template<class First , class ... Next>
void	addFilters (First &&first, Next &&...next)
	Adds an arbitrary number of filters (Lagrangian or diagram filters) to the options. More...

void	resetFilters ()
	Resets the filters (for lagrangian and diagrams) to the default ones, i.e. removing all user-defined ones.

Data Fields
bool	orderInsertions { mty::option::applyInsertionOrdering }
	This option (default = true) implies that fermionic insertions are ordered using a given rule. More...

bool	orderExternalFermions { mty::option::orderExternalFermions }
	Boolean telling if external fermions must be ordered in the result. More...

bool	simplifyAmplitudes { mty::option::simplifyAmplitudes }
	Set this option to false if you want to disable all simplifications of amplitudes. More...

bool	discardLowerOrders { mty::option::discardLowerOrders }
	Set this option to false if you want the tree-level diagrams to appear in the same amplitude as the one-loop calculation.

bool	verboseAmplitude { mty::option::verboseAmplitude }
	Set this options to false to disable all prints during calculations.

bool	partialCalculation { false }
	Set this option to true to disable the DiagramFilters if the calculation is only a part of the full calculation.

Protected Member Functions
void	addLagrangianFilter (LagrangianFilter const &filter)
	Adds one Lagrangian filter to the options. More...

void	addDiagramFilter (DiagramFilter const &filter)
	Adds one diagram filter to the options. More...

void	addLagrangianFilters (std::initializer_list< LagrangianFilter > filters)
	Adds a list of Lagrangian filters to the options. More...

void	addDiagramFilters (std::initializer_list< DiagramFilter > filters)
	Adds a list of diagram filters to the options. More...

Private Member Functions
template<class Container , class Predicate >
void	applyFilters (Container &container, Predicate const &predicate) const
	Helper private class applying a set of filters on a range. More...

void	initDefaultFilters ()
	Initializes the default filters.

void	setWilsonOperatorBasis (OperatorBasis basis)
	Sets the Wilson operator basis wilsonOperatorBasis. More...

Private Attributes
bool	feynRuleCalculation { false }
	Mode of an amplitude calculation. More...

std::shared_ptr< int >	loopOrder
	Loop order (0 for tree-level, 1 for one-loop). More...

int	expansionOrder
	Taylor expansion order for an amplitude calculation (expansion of the lagrangian exponential).

int	topology = mty::Topology::Any
	Topology allowed for the calculation. The default is mty::Topology::Any.

std::vector< int >	fermionOrder
	Order for fermions in bilinears. More...

std::vector< LagrangianFilter >	lfilters
	List of lagrangian filters. More...

std::vector< DiagramFilter >	dfilters
	List of diagram filters. More...

csl::Expr	wilsonOperatorCoefficient { CSL_1 }
	Prefactor used for Wilson coefficients. More...

OperatorBasis	wilsonOperatorBasis = OperatorBasis::Chiral
	Operator basis for Wilson coefficients. More...

Static Private Attributes
static constexpr size_t	nDefaultDiagramFilters = 1

Detailed Description

Instances of this class can be given to mty::Model when launching a calculation to customize the output.

Member Typedef Documentation

◆ DiagramFilter

using mty::FeynOptions::DiagramFilter = std::function<bool(mty::FeynmanDiagram const&)>

Type definition for a Feynman diagram.

A Feynman diagram filter is a boolean predicate (function, lambda, ...) taking a mty::FeynmanDiagram as parameter (const reference) and returning true if the diagram must be kept.

◆ LagrangianFilter

using mty::FeynOptions::LagrangianFilter = std::function<bool(mty::InteractionTerm const&)>

Type definition for a Lagrangian filter.

A Lagrangian filter is a boolean predicate (function, lambda, ...) taking a mty::InteractionTerm as parameter (const reference) and returning true if the vertex must be kept.

Constructor & Destructor Documentation

◆ FeynOptions()

mty::FeynOptions::FeynOptions ( )

Default constructor, only constructor of this class (expect copy and move).

This constructor initializes default Lagrangian and Feynman diagram filters used in all calculations.

Member Function Documentation

◆ addDiagramFilter()

void mty::FeynOptions::addDiagramFilter ( DiagramFilter const & filter )

inlineprotected

Adds one diagram filter to the options.

This function delegates to the other overload that takes an arbitrary number of filters.

Parameters

filter Unique filter to add.

◆ addDiagramFilters()

void mty::FeynOptions::addDiagramFilters ( std::initializer_list< DiagramFilter > filters )

protected

Adds a list of diagram filters to the options.

Parameters

filters List of filters.

◆ addFilter()

template<class Filter >

void mty::FeynOptions::addFilter ( Filter && filter )

inline

Adds one filter (LagrangianFilter or DiagramFilter) to the options.

Depending on the type (deduced at compile-time) of the filter, this function delegates to addLagrangianFilter() or addDiagramFilter().

Template Parameters

Filter Type of the filter given as parameter.

Parameters

filter User-defined predicate respecting the requirements of LagrangianFilter or DiagramFilter types.

See also: addFilters()

◆ addFilters() [1/2]

void mty::FeynOptions::addFilters ( )

inline

Overloads to add 0 filter (this function does nothing).

This function represents the end-point of the compile-time recursion of the templated overload.

◆ addFilters() [2/2]

template<class First , class ... Next>

void mty::FeynOptions::addFilters	(	First &&	first,
		Next &&...	next
	)

inline

Adds an arbitrary number of filters (Lagrangian or diagram filters) to the options.

This function accepts an arbitrary number of arguments provided that each of them is either a LagrangianFilter or a DiagramFilter. The compiler deduces automatically the types and the function can be used as simply as

FeynOptions options;
options.addFilter(
    // diagram filter:
    mty::filters::forceParticle("t"), // only top quark contrib
    // Lagrangian filter:
    mty::filters::disableParticle("Z"), // no Z boson
    // Another diagram filter:
    mty::filters::disableParticleCombination({"e", "mu"}) // Disables combinations of e and mu in the same diagram
);

Template Parameters

First	Type of the first filter given.
...Next	Types of the next filters.

Parameters

first	First filter.
...next	Next filters.

◆ addLagrangianFilter()

void mty::FeynOptions::addLagrangianFilter ( LagrangianFilter const & filter )

inlineprotected

Adds one Lagrangian filter to the options.

This function delegates to the other overload that takes an arbitrary number of filters.

Parameters

filter Unique filter to add.

◆ addLagrangianFilters()

void mty::FeynOptions::addLagrangianFilters ( std::initializer_list< LagrangianFilter > filters )

protected

Adds a list of Lagrangian filters to the options.

Parameters

filters List of filters.

◆ applyFilters() [1/4]

void mty::FeynOptions::applyFilters ( std::vector< Lagrangian::TermType > & lagrangian ) const

Applies the Lagrangian filters on a vector of vertices.

The vector must contain mty::Lagrangian::TermType objects even if the filters themselves take mty::InteractionTerm. This function removes from the vector all interaction terms for which one of the filters returns false (filter out).

Parameters

lagrangian Lagrangian Set of interaction terms to filter.

See also: lfilters, addFilter(), addFilters()

◆ applyFilters() [2/4]

std::vector< FeynmanRule const * > mty::FeynOptions::applyFilters ( std::vector< FeynmanRule > const & lagrangian ) const

Filters a set a Feynman rules using the lagrangian filters.

This function uses the interaction term represented by the different rules and applies the Lagrangian filters. Unlike the other filtering functions, this one does not remove the elements inside the initial vector but returns a newly constructed vector containing pointers to the rules that passed all filters (i.e. for which all filters returned true). This allows to avoid any copy of a FeynmanRule object that is a high cost operation.

Parameters

lagrangian Set of Feynman rules (interpreted here as a lagrangian with respect to filters).

Returns: A vector containing all pointers to FeynmanRule objects that passed the filters.

See also: lfilters, addFilter(), addFilters()

◆ applyFilters() [3/4]

void mty::FeynOptions::applyFilters	(	std::vector< FeynmanDiagram > &	diagrams,
		bool	forceFilters = `false`
	)		const

Applies the diagram filters on a vector of Feynman diagrams.

This function removes from the vector all diagrams for which one of the filters returns false (filter out).

Parameters

diagrams	Set of diagrams to filter.
forceFilters	Boolean that ensures (is true) that the filters are applied whatever are the other options (partialCalculation in particular).

See also: dfilters, addFilter(), addFilters()

◆ applyFilters() [4/4]

template<class Container , class Predicate >

void mty::FeynOptions::applyFilters	(	Container &	container,
		Predicate const &	predicate
	)		const

inlineprivate

Helper private class applying a set of filters on a range.

Template Parameters

Container	Type of the container to filter.
Predicate	Predicate type to apply.

Parameters

container	Container on which the filter is applied.
predicate	Inversed filter, must return true if the object must be filtered out.

◆ getDiagramFilters()

std::vector<DiagramFilter> const& mty::FeynOptions::getDiagramFilters ( ) const

inline

Returns: dfilters

◆ getExpansionOrder()

int mty::FeynOptions::getExpansionOrder ( ) const

inline

Returns: expansionOrder

◆ getFermionOrder()

std::vector<int> const& mty::FeynOptions::getFermionOrder ( ) const

inline

Returns: fermionOrder

◆ getFeynRuleCalculation()

bool mty::FeynOptions::getFeynRuleCalculation ( ) const

inline

Returns: feynRuleCalculation

◆ getLagrangianFilters()

std::vector<LagrangianFilter> const& mty::FeynOptions::getLagrangianFilters ( ) const

inline

Returns: lfilters

◆ getLoopOrder()

int mty::FeynOptions::getLoopOrder ( ) const

inline

Returns: The value pointed by loopOrder

◆ getTopology()

int mty::FeynOptions::getTopology ( ) const

inline

Returns: topology

◆ getWilsonOperatorBasis()

OperatorBasis mty::FeynOptions::getWilsonOperatorBasis ( ) const

inline

Returns: wilsonOperatorBasis

◆ getWilsonOperatorCoefficient()

csl::Expr mty::FeynOptions::getWilsonOperatorCoefficient ( ) const

inline

Returns: wilsonOperatorCoefficient

◆ passFilters()

bool mty::FeynOptions::passFilters ( FeynmanDiagram const & diagram ) const

Tells if a diagram passes all diagram filters.

Parameters

diagram

Returns

◆ setFermionOrder()

void mty::FeynOptions::setFermionOrder ( std::vector< int > const & order )

Sets the fermion order used to express the amplitude.

Parameters

order Fermion order to apply, range of integers from $ 0 $ to $ N-1 $ for $ N $ external fermions in the process.

See also: fermionOrder

◆ setFeynmanRuleMode()

void mty::FeynOptions::setFeynmanRuleMode ( )

Sets the value of feynRuleCalculation to true (the default value of this member is false).

This function will probably not be useful for user-level manipulations.

◆ setLoopOrder()

void mty::FeynOptions::setLoopOrder	(	int	t_nLoops,
		int	nExternalLegs
	)

Sets the number of loops for the calculation.

This function needs not only the loop order, but also the number of external legs in the process as it will determine, together with the number of loop, the Taylor expansion order of the Lagrangian exponential.

Parameters

t_nLoops	Number of loops wanted (basically 0 or 1).
nExternalLegs	Number of external legs of the process.

◆ setTopology()

void mty::FeynOptions::setTopology ( int t_topology )

Sets the topology for the calculation.

Parameters

t_topology Topologies allowed.

See also: mty::Topology

◆ setWilsonOperatorBasis()

void mty::FeynOptions::setWilsonOperatorBasis ( OperatorBasis basis )

private

Sets the Wilson operator basis wilsonOperatorBasis.

Note: This method is private because the operator basis is for now fixed to the standard basis, more suitable for identification.

Parameters

basis Basis used in Wilson coefficient decomposition.

◆ setWilsonOperatorCoefficient()

void mty::FeynOptions::setWilsonOperatorCoefficient ( csl::Expr const & factor )

Sets the Wilson operator coefficient wilsonOperatorCoefficient.

Parameters

factor Factor used in Wilson coefficient decomposition.

Field Documentation

◆ dfilters

std::vector<DiagramFilter> mty::FeynOptions::dfilters

private

List of diagram filters.

Those filters are applied by MARTY once the Wick theorem has been applied, i.e. that all possible diagrams have been found. They save less calculation than LagrangianFilter but are more general as one can filter diagrams on more complex conditions.

See also: filters.h for built-in filters

◆ fermionOrder

std::vector<int> mty::FeynOptions::fermionOrder

private

Order for fermions in bilinears.

The order of fermions in the result in fixed, useful for Wilson coefficient extraction. For example, a process with for external fermions $ \psi_0,\ \psi_1,\ \psi_2 $ and $ \psi_3 $ can be expressed with the order $ (0123) $ with terms of the type

\[ \left(\bar{\psi}_0\Gamma^A\psi_1\right) \left(\bar{\psi}_1\Gamma^B\psi_2\right, \]

while an order $ (2013) $ corresponds to something such as

\[ \left(\bar{\psi}_2\Gamma^C\psi_0\right) \left(\bar{\psi}_1\Gamma^D\psi_3\right, \]

with $ \Gamma^{A,B,C,D} $ arbitrary $ \gamma $-matrix combinations.

◆ feynRuleCalculation

bool mty::FeynOptions::feynRuleCalculation { false }

private

Mode of an amplitude calculation.

If true, the calculation is done to derive Feynman rules, false otherwise. The derivation of Feynman rules is a more involved calculation and is used only in that purpose. Otherwise, Feynman rules are used. This parameter is handled automatically by MARTY when calculating Feynman rules, it should not be set by the user a priori.

◆ lfilters

std::vector<LagrangianFilter> mty::FeynOptions::lfilters

private

List of lagrangian filters.

Those filters are applied by MARTY before any calculation is done by discarding unwanted interaction terms. This type of filter must be preferred to diagram filters if possible.

See also: filters.h for built-in filters

◆ loopOrder

std::shared_ptr<int> mty::FeynOptions::loopOrder

private

Loop order (0 for tree-level, 1 for one-loop).

This variable is stored in a shared pointer for a technical reason, but the interface (getter and setter functions) use a standard integer.

◆ orderExternalFermions

bool mty::FeynOptions::orderExternalFermions { mty::option::orderExternalFermions }

Boolean telling if external fermions must be ordered in the result.

This option is false by default and should not be set to true except for Wilson coefficient calculations because it requires more calculations and it not relevant when calculating a squared amplitude.

◆ orderInsertions

bool mty::FeynOptions::orderInsertions { mty::option::applyInsertionOrdering }

This option (default = true) implies that fermionic insertions are ordered using a given rule.

This only affects the absolute signs of different diagrams in a process and is then physically irrelevant.

◆ simplifyAmplitudes

bool mty::FeynOptions::simplifyAmplitudes { mty::option::simplifyAmplitudes }

Set this option to false if you want to disable all simplifications of amplitudes.

Using this option, the result is then much closer to the bare use of Feynman rules and propagators.

◆ wilsonOperatorBasis

OperatorBasis mty::FeynOptions::wilsonOperatorBasis = OperatorBasis::Chiral

private

Operator basis for Wilson coefficients.

The chiral basis uses projectors $ P_L,P_R $ whereas the standard one uses $ \1,\gamma^5 $.

◆ wilsonOperatorCoefficient

csl::Expr mty::FeynOptions::wilsonOperatorCoefficient { CSL_1 }

private

Prefactor used for Wilson coefficients.

An amplitude is decomposed on pairs of Wilson coefficients and operators the following way:

\[ i\mathcal{M} \equiv -if\sum _i C_i \hat{\mathcal{O}}_i, \]

with $ C_i $ the Wilson coefficients, $ \hat{\mathcal{O}}_i $ the operators, and $f$ a convention-dependent factor. This member corresponds to the $ f $used by MARTY when calculating the $ C_i $.

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

include/feynOptions.h
src/feynOptions.cpp

Public Types

Public Member Functions

Data Fields

Protected Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Member Typedef Documentation

◆ DiagramFilter

◆ LagrangianFilter

Constructor & Destructor Documentation

◆ FeynOptions()

Member Function Documentation

◆ addDiagramFilter()

◆ addDiagramFilters()

◆ addFilter()

◆ addFilters() [1/2]

◆ addFilters() [2/2]

◆ addLagrangianFilter()

◆ addLagrangianFilters()

◆ applyFilters() [1/4]

◆ applyFilters() [2/4]

◆ applyFilters() [3/4]

◆ applyFilters() [4/4]

◆ getDiagramFilters()

◆ getExpansionOrder()

◆ getFermionOrder()

◆ getFeynRuleCalculation()

◆ getLagrangianFilters()

◆ getLoopOrder()

◆ getTopology()

◆ getWilsonOperatorBasis()

◆ getWilsonOperatorCoefficient()

◆ passFilters()

◆ setFermionOrder()

◆ setFeynmanRuleMode()

◆ setLoopOrder()

◆ setTopology()

◆ setWilsonOperatorBasis()

◆ setWilsonOperatorCoefficient()

Field Documentation

◆ dfilters

◆ fermionOrder

◆ feynRuleCalculation

◆ lfilters

◆ loopOrder

◆ orderExternalFermions

◆ orderInsertions

◆ simplifyAmplitudes

◆ wilsonOperatorBasis

◆ wilsonOperatorCoefficient