Phase Space Description

AbstractParticleStateful <: QEDbase.AbstractParticle

Abstract base type for the representation of a particle with a state. It requires the following interface functions to be provided:

• particle_direction: Returning the particle's direction.
• particle_species: Returning the particle's species.
• momentum: Returning the particle's momentum.

Implementations for is_fermion, is_boson, is_particle, is_anti_particle, is_incoming, is_outgoing, mass, and charge are automatically provided using the interface functions above to fulfill the QEDbase.AbstractParticle interface.

momentum(part::AbstractParticleStateful)

Interface function that must return the particle's AbstractFourMomentum.

AbstractPhaseSpacePoint{PROC, MODEL, PSL, IN_PARTICLES, OUT_PARTICLES}

Representation of a point in the phase space of a process. It has several template arguments:

• PROC <:AbstractProcessDefinition
• MODEL <:AbstractModelDefinition
• PSL <:AbstractPhaseSpaceLayout
• IN_PARTICLES <:Tuple{Vararg{AbstractParticleStateful}}: The tuple type of all the incoming [AbstractParticleStateful`](@ref)s.
• OUT_PARTICLES <:Tuple{Vararg{AbstractParticleStateful}}: The tuple type of all the outgoing [AbstractParticleStateful`](@ref)s.

The following interface functions must be provided:

• Base.getindex(psp::AbstractPhaseSpacePoint, dir::ParticleDirection, n::Int): Return the nth AbstractParticleStateful of the given direction. Throw BoundsError for invalid indices.
• particles(psp::AbstractPhaseSpacePoint, dir::ParticleDirection): Return the particle tuple (type IN_PARTICLES or OUT_PARTICLES depending on dir)
• process: Return the process.
• model: Return the model.
• phase_space_layout: Return the phase space layout.

From this, the following functions are automatically derived:

• momentum(psp::AbstractPhaseSpacePoint, dir::ParticleDirection, n::Int): Return the momentum of the nth AbstractParticleStateful of the given direction.
• momenta(psp::PhaseSpacePoint, ::ParticleDirection): Return a Tuple of all the momenta of the given direction.

Furthermore, an implementation of an AbstractPhaseSpacePoint has to verify on construction that it is valid, i.e., the following conditions are fulfilled:

• IN_PARTICLES must match incoming_particles(::PROC) in length, order, and type or be an empty Tuple.
• OUT_PARTICLES must match the outgoing_particles(::PROC) in length, order, and type, or be an empty Tuple.
• IN_PARTICLES and OUT_PARTICLES may not both be empty.

If IN_PARTICLES is non-empty, AbstractPhaseSpacePoint <: AbstractInPhaseSpacePoint is true. Likewise, if OUT_PARTICLES is non-empty, AbstractPhaseSpacePoint <: AbstractOutPhaseSpacePoint is true. Consequently, if both IN_PARTICLES and OUT_PARTICLES are non-empty, both <: statements are true.

AbstractInPhaseSpacePoint

A partial type specialization on AbstractPhaseSpacePoint which can be used for dispatch in functions requiring only the in channel of the phase space to exist, for example implementations of _incident_flux. No restrictions are imposed on the out-channel, which may or may not exist.

See also: AbstractOutPhaseSpacePoint

AbstractOutPhaseSpacePoint

A partial type specialization on AbstractPhaseSpacePoint which can be used for dispatch in functions requiring only the out channel of the phase space to exist. No restrictions are imposed on the in-channel, which may or may not exist.

See also: AbstractInPhaseSpacePoint

process(psp::AbstractPhaseSpacePoint)

Return the phase space point's set process.

See also: AbstractProcessDefinition

model(psp::AbstractPhaseSpacePoint)

Return the phase space point's set model.

See also: AbstractModelDefinition

phase_space_layout(psp::AbstractPhaseSpacePoint)

Return the phase space point's set phase space layout.

See also: AbstractPhaseSpaceLayout

particle_direction(part::AbstractParticleStateful)

Interface function that must return the particle's ParticleDirection.

particle_species(part::AbstractParticleStateful)

Interface function that must return the particle's AbstractParticleType, e.g. QEDcore.Electron().

momenta(psp::AbstractPhaseSpacePoint, ::ParticleDirection)

Return a Tuple of all the particles' momenta for the given ParticleDirection.