Amplitude
Amplitude
is a database of Feynman amplitudes. Amplitude["name"]
returns the amplitude corresponding to the string "name"
. A list of all defined names is obtained with Amplitude[]
. New amplitudes can be added to the file "Amplitude.m"
. It is strongly recommended to use names that reflect the process.
The option Gauge -> 1
means `t Hooft Feynman gauge;
Polarization -> 0
gives unpolarized OPE-type amplitudes, Polarization -> 1
the polarized ones.
See also
Overview, FeynAmp.
Examples
98
This is the amplitude of a gluon self-energy diagram:
Amplitude["se1g1"]
Explicit[%]
SUNDeltaContract(fFCGV(a)FCGV(c)FCGV(e)fFCGV(b)FCGV(d)FCGV(f)ΠFCGV(e)FCGV(f)FCGV(β)FCGV(σ)(FCGV(q))VFCGV(μ)FCGV(α)FCGV(β)(FCGV(p), FCGV(q)−FCGV(p), −FCGV(q))VFCGV(ν)FCGV(ρ)FCGV(σ)(−FCGV(p), FCGV(p)−FCGV(q), FCGV(q))ΠFCGV(c)FCGV(d)FCGV(α)FCGV(ρ)(FCGV(p)−FCGV(q)))
−FCGV(q)2(FCGV(p)−FCGV(q))21gs2gFCGV(α)FCGV(ρ)gFCGV(β)FCGV(σ)fFCGV(a)FCGV(d)FCGV(f)fFCGV(b)FCGV(d)FCGV(f)(gFCGV(β)FCGV(μ)(−FCGV(p)FCGV(α)−FCGV(q)FCGV(α))+gFCGV(α)FCGV(μ)(2FCGV(p)FCGV(β)−FCGV(q)FCGV(β))+gFCGV(α)FCGV(β)(2FCGV(q)FCGV(μ)−FCGV(p)FCGV(μ)))(gFCGV(ρ)FCGV(σ)(FCGV(p)FCGV(ν)−2FCGV(q)FCGV(ν))+gFCGV(ν)FCGV(σ)(FCGV(p)FCGV(ρ)+FCGV(q)FCGV(ρ))+gFCGV(ν)FCGV(ρ)(FCGV(q)FCGV(σ)−2FCGV(p)FCGV(σ)))