Physics
Maple provides a state-of-the-art environment for algebraic computations in Physics, with emphasis on ensuring that the computational experience is as natural as possible. The theme of the Physics project for Maple 2023 has been the use of the package in Education, new commands, the consolidation of the functionality introduced in previous releases, also related to the StandardModel package, and several enhancements necessary for producing the new Courseware-Support, Mechanics material.
As part of its commitment to providing the best possible computational environment in Physics, Maplesoft launched a Maple Physics: Research and Development website in 2014, which enabled users to download research versions of the package, ask questions, and provide feedback. The results from this accelerated exchange have been incorporated into the Physics package in Maple 2023. The presentation below illustrates both the novelties and the kind of mathematical formulations that can now be performed.
Courseware support: Mechanics
New command Lagrange Equations
New command Substitute
New command StandardModel:-Lagrangian
New Physics:-Library commands: FactorSum and RemoveCommonFactors
New coordinates labels
Documentation advanced examples
See Also
The Physics package, with its various subpackages, is now a resourceful, mature project. For Maple 2023, part of the focus has been in its use in Education in Physics, starting with Mechanics. The resulting material is now part of Maple's help system and can be opened to interact with it as a Maple document. The presentation is organized as a hyperlinked syllabus covering typical topics appearing in Mechanics undergrad courses of the first years. For the Maple 2023 release, Part I covers:
Position, velocity and acceleration in Cartesian, cylindrical and spherical coordinates
The position r→⁡tas a function of time
The velocity v→⁡t
The acceleration a→t
Deriving these formulas
Velocity and acceleration in the case of 2-dimensional motion on the x, y plane
The equations of motion
A single particle
The equations of motion - vectorial form
The case of constant acceleration
Motion under gravitational force close to the Earth's surface
Motion under gravitational force not close to the Earth's surface
Circular motion
Escape velocity
Different acceleration in different regions
The equations of motion using tensor notation
Cartesian coordinates
Curvilinear coordinates
Many-particle systems
Center of mass
Static: reactions of planes and tensions on cables
Lagrange equations
Motion of a pendulum
Conservation laws
Work
Conservation of the total energy of a closed system or a system in a constant external field
Conservation of the total momentum of a closed system
Conservation of angular momentum
Cyclic coordinates
Integration of the equations of motion
Motion in one dimension
Reduced mass
The two-body problem
A many-body problem
Motion in a central field
Kepler's problem
Small Oscillations
Free oscillations in one dimension
Forced oscillations
Oscillations of systems with many degrees of freedom
Rigid-body motion
Angular velocity
Inertia tensor
Angular momentum of a rigid body
The equations of motion of a rigid body
Non-inertial coordinate systems
Coriolis force and centripetal force
There is now a new Physics command, LagrangeEquations, taking advantage of the functional differentiation capabilities. LagrangeEquations receives an expression representing a Lagrangian and returns a sequence of Lagrange equations with as many equations as coordinates are indicated. The formula in the traditional case where the Lagrangian depends on 1st order derivatives of the coordinates and there is only one parameter, t, is
ⅆⅆt∂∂v→iL=∂∂r→iL
where ∂∂r→iL formally represents the derivative with respect to the coordinates of the ith particle, equal to the Gradient when working in Cartesian coordinates; ∂∂v→iL represents the equivalent operation, replacing each coordinate by the corresponding generalized velocity and ⅆⅆt represents the total derivative with respect to t, the parameter parametrizing the coordinates. In more general cases the number of parameters can be many. For example, in electrodynamics, the "coordinate" is a tensor field Aμ⁡x,y,z,t, there are then four coordinates, one for each of the values of the index μ, and there are four parameters x,y,z,t. LagrangeEquations can handle tensors and vectors of the Physics package as well as derivatives using vectorial differential operators (see d_ and Nabla), works by performing functional differentiation (see Fundiff), and handles 1st, and higher order derivatives of the coordinates in the Lagrangian automatically.
Examples
withPhysics:
Setupmathematicalnotation=true,coordinates=cartesian
coordinatesystems=X,mathematicalnotation=true
The Lagrangian of a one-dimensional oscillator - small oscillations
L≔12⁢diff⁡x⁡t,t2−12⁢k⁢x⁡t2
L≔x.⁡t22−k⁢x⁡t22
The corresponding Lagrange equation gives Newton's second law, a 2nd order linear ODE for x⁡t
LagrangeEquations⁡L,x
x..⁡t+x⁡t⁢k=0
The Lagrangian of a pendulum of mass m and length l where the suspension point moves uniformly over a vertical circumference centered at the origin, with a constant frequency ω
CompactDisplay⁡φ⁡t
φ⁡t⁢will now be displayed as⁢φ
L≔12⁢m⁢−2⁢diff⁡φ⁡t,t⁢a⁢l⁢ω⁢sin⁡ω⁢t−φ⁡t+diff⁡φ⁡t,t2⁢l2+2⁢cos⁡φ⁡t⁢g⁢l
L≔m⁢−2⁢φ.⁢a⁢l⁢ω⁢sin⁡ω⁢t−φ+φ.2⁢l2+2⁢cos⁡φ⁢g⁢l2
The Lagrange equations
LagrangeEquations⁡L,φ
−m⁢l⁢−a⁢ω2⁢cos⁡ω⁢t−φ+φ..⁢l+sin⁡φ⁢g=0
The Maxwell equations can be derived as Lagrange equations as follows. For simplicity, consider Maxwell equations in vacuum. Define first a tensor representing the 4D electromagnetic field potential
Define⁡Aμ
Aμ,γμ,σμ,∂μ,gμ,ν,εα,β,μ,ν,Xμ
The electromagnetic field tensor
Fμ,ν≔d_μ⁡Aν⁡X−d_ν⁡Aμ⁡X
Fμ,ν≔∂μ⁡Aν⁡X−∂ν⁡Aμ⁡X
The Lagrangian
L≔Fμ,ν2
L≔∂μ⁡Aν⁡X−∂ν⁡Aμ⁡X⁢∂⁢μ⁢μ⁡A⁢ν⁢ν⁡X−∂⁢ν⁢ν⁡A⁢μ⁢μ⁡X
Maxwell equations in 4D tensorial notation
LagrangeEquations⁡L,A
−4⁢□⁡A⁢α⁢α⁡X+4⁢∂μ⁡∂⁢α⁢α⁡A⁢μ⁢μ⁡X=0
The command for doing syntactical exact-match substitutions is subs. Frequently, however, what we intend to accomplish with a substitution is more of a mathematical substitution. For different kinds of mathematical substitutions Maple has the commands algsubs, Physics:-SubstituteTensor, Physics:-SubstituteTensorIndices, Physics:-Library:-SubstituteOperator and Physics:-Library:-SubstituteMatrix, resulting in a myriad of commands, useful, however difficult to remember. A new single command, Physics:-Substitute, unifies all of those so that one does not need to remember which one to use.
restart;withPhysics:
Substitutions of sub-products and sub-sums, possibly involving noncommutative objects
eq≔F+A⁢B⁡x=Ej
ee≔A⁢B⁡x⁢C
Substitute⁡eq,ee
−C⁢F−Ej
Substitution of matrices and vectors taking mathematical equality into account
eq≔alpha + Matrix2,symbol=a=β+Matrix2,symbol=b
eq≔α+a1,1a1,2a2,1a2,2=β+b1,1b1,2b2,1b2,2
ee≔Matrix⁡2,symbol=a
ee≔a1,1a1,2a2,1a2,2
Substituteeq,ee
−α+β+b1,1b1,2b2,1b2,2
Set up some non-commutative operands for substitution
Setupquantumoperators=A,B,C,E,F:
Some typical examples not handled by subs, eval or algsubs
eq≔F+A⁢B=E
ee≔exp⁡λ⁢A⁢B⁢C⁢B⁢exp⁡−λ A B C
ee≔ⅇλ⁢A⁢B⁢C⁢B⁢ⅇ−λ⁢A⁢B⁢C
ⅇλ⁢E−F⁢C⁢B⁢ⅇ−λ⁢E−F⁢C
Substituting tensorial sub-expressions
DefineA,B,C,F,G:
Defined objects with tensor properties
eq≔Aμ=Gν,α⁢Aα⁢Fμ,ν
eq≔Aμ=Aα⁢Fμ,ν⁢G⁢ν,α⁢ν,α
ee≔Aν⁢Aν
ee≔Aν⁢A⁢ν⁢ν
Aα⁢Fν,β⁢G⁢β,α⁢β,α⁢Aκ⁢F⁢νλ⁢νλ⁢G⁢λ,κ⁢λ,κ
Setup⁡spinorindices=lowercaselatin_is
spinorindices=lowercaselatin_is
Define⁡Tμ,i,j
A,B,C,F,G,γμ,σμ,Tμ,i,j,∂μ,gμ,ν,εα,β,μ,ν
Substitute⁡Dgammaμi,j=Tμ,i,j,Dgamma~alpha~k,m, disregardfreeindices
T⁢α,km⁢α,km
Substitutions of tensor indices
g_α,μ⁢A~mu⁢g_~alpha,~nu⁢Bν,σ,~rho
gα,μ⁢g⁢α,ν⁢α,ν⁢A⁢μ⁢μ⁢Bν,σρν,σρ
Check⁡,all
α,μ,ν,σ,~rho
Substitute⁡α=β,mu=delta, sigma=rho,
gβ,δ⁢g⁢β,ν⁢β,ν⁢A⁢δ⁢δ⁢Bν,ρρν,ρρ
One of the distinctive aspects of the Standard Model is the complexity of its Lagrangian. In this context, the new StandardModel:-Lagrangian returns the Lagrangian of the model after symmetry breaking, optionally restricted to only the interaction terms, or only one of its QED, QCD or electroweak sectors, or only one of the different sub-terms involved in the electroweak part; all of that with the covariant derivatives, and sums over leptons and quarks optionally expanded.
The algebraic expressions returned by Lagrangian are fully computable, so you can use them as starting point to construct other Lagrangians (add or subtract terms), or the Action and related field equations (see d_, D_ for covariant derivatives, diff and Fundiff for functional differentiation), or to compute scattering amplitudes (see FeynmanDiagrams and FeynmanIntegral).
restart;withPhysics:withStandardModel
⁢_______________________________________________________
Setting lowercaselatin_is letters to represent Dirac spinor indices
Setting lowercaselatin_ah letters to represent SU(3) adjoint representation, (1..8) indices
Setting uppercaselatin_ah letters to represent SU(3) fundamental representation, (1..3) indices
Setting uppercaselatin_is letters to represent SU(2) adjoint representation, (1..3) indices
Setting uppercasegreek letters to represent SU(2) fundamental representation, (1..2) indices
Defined as the electron, muon and tau leptons and corresponding neutrinos: ej , μj , τj , νej , νμj , ντj
Defined as the up, charm, top, down, strange and bottom quarks: uA,j , cA,j , tA,j , dA,j , sA,j , bA,j
Defined as gauge tensors: Bμ , 𝔹μ,ν , Aμ , 𝔽μ,ν , Wμ,J , 𝕎μ,ν,J , W+μ , 𝕎+μ,ν , W−μ , 𝕎−μ,ν , Zμ , ℤμ,ν , Gμ,a , 𝔾μ,ν,a
Defined as Gell-Mann (Glambda), Pauli (Psigma) and Dirac (Dgamma) matrices: λa , σJ , γμ
Defined as the electric, weak and strong coupling constants: g__e, g__w, g__s
Defined as the charge in units of |g__e| for 1) the electron, muon and tauon, 2) the up, charm and top, and 3) the down, strange and bottom: q__e = −1, q__u = 23, q__d = −13
Defined as the weak isospin for 1) the electron, muon and tauon, 2) the up, charm and top, 3) the down, strange and bottom, and 4) all the neutrinos: I__e = −12, I__u = 12, I__d = −12, I__n = 12
You can use the active form without the % prefix, or the 'value' command to give the corresponding value to any of the inert representations q__e, q__u, q__d, I__e, I__u, I__d, I__n
⁢Default differentiation variables for d_, D_ and dAlembertian are:⁢X=x,y,z,t
Minkowski spacetime with signatre - - - +
I__d,I__e,I__n,I__u,q__d,q__e,q__u,BField,BFieldStrength,Bottom,CKM,Charm,Down,ElectromagneticField,ElectromagneticFieldStrength,Electron,ElectronNeutrino,FSU3,Glambda,GluonField,GluonFieldStrength,HiggsBoson,Lagrangian,Muon,MuonNeutrino,Strange,Tauon,TauonNeutrino,Top,Up,WField,WFieldStrength,WMinusField,WMinusFieldStrength,WPlusField,WPlusFieldStrength,WeinbergAngle,ZField,ZFieldStrength,g__e,g__s,g__w
The massless fields of the model are the electromagnetic and gluon fields and the three neutrinos
Setupmassless
masslessfields=G,νμ,ντ,A,νe
The Leptons and Quarks of the model are
StandardModel:-Leptons
e,μ,τ,νe,νμ,ντ
StandardModel:-Quarks
u,c,t,d,s,b
The Gauge fields, and their related field strengths displayed with Open Face type fonts
StandardModel:-GaugeFields
A,𝔽,B,𝔹,W,𝕎,G,𝔾,W−,𝕎−,W+,𝕎+,Z,ℤ
To represent the interaction Lagrangians for the QCD and electroweak sectors as sums over leptons and quarks, all of them fermions, it is useful to introduce four anticommutative prefixes, used below as summation indices in the formulas
Setupanticommutativeprefix=f__D,f__L,f__Q,f__U
anticommutativeprefix=f__D,f__L,f__Q,f__U
For readability, omit from the display of formulas the functionality of all the fields entering the Standard Model (see CompactDisplay) and use the lowercase i instead of the uppercase I to represent the imaginary unit
CompactDisplayStandardModel:-Leptons,StandardModel:-Quarks,StandardModel:-GaugeFields,HiggsBoson,f__L,f__Q,f__U,f__D⁡X,quiet: interfaceimaginaryunit=i:
The Lagrangian of the whole Standard Model after symmetry breaking, in its most compact form:
Lagrangian
∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢ⅈ⁢γμj,k⁢▿μ−mf__Q⁢δj,k⁢f__QA,k−𝔾μ,ν,a24−𝔽μ,ν24−𝕎+μ,ν⁢𝕎−μ,ν2+mW2⁢W+μ⁢W−μ−ℤμ,ν24+mZ2⁢Zμ22+∂μ⁡Φ22−mΦ2⁢Φ22+∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__Lk−mf__L⁢f__Lj+∑f__L=νe,νμ,ντ⁡ⅈ⁢γμj,k⁢f__Lj&conjugate0;⁢∂μ⁡f__Lk+∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__QA,k−mf__Q⁢f__QA,j+g__e⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Aμ+g__w⁢γμj,k⁢δk,l+γ5k,l⁢I__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Ll+I__n⁢∑f__L=νe,νμ,ντ⁡f__Lj&conjugate0;⁢f__Ll+I__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,l+I__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,l−sin⁡θw2⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Zμcos⁡θw−g__w⁢2⁢γμj,k⁢δk,l+γ5k,l⁢∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D⁢f__UA,j&conjugate0;⁢f__DA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L1j⁡X&conjugate0;⁢f__L2l⁡X⁢W+μ+∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D&conjugate0;⁢f__DA,j&conjugate0;⁢f__UA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L2j⁡X&conjugate0;⁢f__L1l⁡X⁢W−μ2−g__w⁢mΦ2⁢Φ3+Φ48⁢mW4⁢mW+g__w⁢ΦmW+g__w2⁢Φ24⁢mW2⁢mW2⁢W+μ⁢W−μ+Zμ2⁢mZ22−ⅈ⁢g__w⁢𝕎+μ,ν⁢W−μ−W+μ⁢𝕎−μ,ν⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw+W−ν⁢W+μ⁢𝔽μ,ν⁢sin⁡θw−ℤμ,ν⁢cos⁡θw−g__w2⁢2⁢W+μ⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw2⁢2⁢W+ν⁢W−ν+Aν⁢sin⁡θw−Zν⁢cos⁡θw2+W+μ⁢W−ν+W+ν⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw24−g__w⁢∑f__L=e,μ,τ,νe,νμ,ντ⁡mf__L⁢f__Lj&conjugate0;⁢f__Lj+∑f__Q=u,c,t,d,s,b⁡mf__Q⁢f__QA,j&conjugate0;⁢f__QA,j⁢Φ2⁢mW
In the output above we see, among other things, the γ5 Dirac matrix, and the Cabibbo - Kobayashi - Maskawa matrix 𝕄, and the tensor indices of different kinds all explicit. See StandardModel for the notational conventions used, which are standard in the literature but for a few things, like a sign in the definition of γ5, that depend on the reference.
The Quantum Electrodynamics (QED) Lagrangian
The simplest sector of this Lagrangian (8) is the QED one
LagrangianQED
ej&conjugate0;⁢ⅈ⁢γμj,k⁢▿⁢μ⁢μ−me⁢δj,k⁢ek−𝔽μ,ν⁢𝔽⁢μ,ν⁢μ,ν4
The applied form can be obtained using the Library command ApplyProductsOfDifferentialOperators over the output (9) or passing the optional argument applied
LagrangianQED,applied
ej&conjugate0;⁢ⅈ⁢▿μ⁡ek⁢γ⁢μ⁢μj,k−me⁢δj,k⁢ek−𝔽μ,ν⁢𝔽⁢μ,ν⁢μ,ν4
Only the interaction part of this Lagrangian is relevant when computing scattering amplitudes. To get that part, you can either expand the covariant derivative operator or or pass the optional keyword expanded, in which case also the trace of 𝔽__μ,ν gets expanded
LagrangianQED,expanded
ⅈ⁢ej&conjugate0;⁢∂μ⁡ek⁢γ⁢μ⁢μj,k−g__e⁢ej&conjugate0;⁢ek⁢Aμ⁢γ⁢μ⁢μj,k−me⁢ej&conjugate0;⁢ej−∂μ⁡Aν−∂ν⁡Aμ⁢∂⁢μ⁢μ⁡A⁢ν⁢ν−∂⁢ν⁢ν⁡A⁢μ⁢μ4
then discard the non-interaction terms
removehas,,d_,m
−γ⁢μ⁢μj,k⁢g__e⁢ej&conjugate0;⁢ek⁢Aμ
or simpler: pass the keyword interaction
LagrangianQED,interaction
All the algebraic expressions returned by Lagrangian are fully computable in that further calculations can proceed starting from them. For example (see FeynmanDiagrams), this is the self-energy of the electron
FeynmanDiagrams,incoming=Electron,outgoing=Electron,numberofloops=1,diagrams
−∫−uel⁡P→1⁢uem⁡P→2&conjugate0;⁢g__e2⁢γ⁢α⁢αm,n⁢γ⁢ν⁢νp,l⁢P__1β+p__2β⁢γ⁢β⁢βn,p+me⁢δn,p⁢gα,ν⁢δ⁡−P__2+P__18⁢π3⁢P__1+p__22−me2+ⅈ⁢ε⁢p__22+ⅈ⁢εⅆp__2 4
The Quantum Chromodynamics (QCD) Lagrangian
Next in complexity is the QCD Lagrangian
LagrangianQCD
∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢ⅈ⁢γμj,k⁢▿⁢μ⁢μ−mf__Q⁢δj,k⁢f__QA,k−𝔾μ,ν,a⁢𝔾⁢μ,νa⁢μ,νa4
LagrangianQCD,expanded
uA,j&conjugate0;⁢ⅈ⁢∂μ⁡uA,k−ⅈ⁢g__s⁢λaA,B⁢uB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−mu⁢δj,k⁢uA,k+cA,j&conjugate0;⁢ⅈ⁢∂μ⁡cA,k−ⅈ⁢g__s⁢λaA,B⁢cB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−mc⁢δj,k⁢cA,k+tA,j&conjugate0;⁢ⅈ⁢∂μ⁡tA,k−ⅈ⁢g__s⁢λaA,B⁢tB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−mt⁢δj,k⁢tA,k+dA,j&conjugate0;⁢ⅈ⁢∂μ⁡dA,k−ⅈ⁢g__s⁢λaA,B⁢dB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−md⁢δj,k⁢dA,k+sA,j&conjugate0;⁢ⅈ⁢∂μ⁡sA,k−ⅈ⁢g__s⁢λaA,B⁢sB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−ms⁢δj,k⁢sA,k+bA,j&conjugate0;⁢ⅈ⁢∂μ⁡bA,k−ⅈ⁢g__s⁢λaA,B⁢bB,k⁢Gμ,a2⁢γ⁢μ⁢μj,k−mb⁢δj,k⁢bA,k−∂μ⁡Gν,a−∂ν⁡Gμ,a+g__s⁢fsu3a,b,c⁢Gμ,b⁢Gν,c⁢∂⁢μ⁢μ⁡G⁢νa⁢νa−∂⁢ν⁢ν⁡G⁢μa⁢μa+g__s⁢fsu3a,d,e⁢G⁢μd⁢μd⁢G⁢νe⁢νe4
For computing scattering amplitudes, only the interaction part of this Lagrangian is relevant
LagrangianQCD,interaction
g__s⁢λaA,B⁢∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢f__QB,k⁢Gμ,a⁢γ⁢μ⁢μj,k2−g__s⁢fsu3a,b,c⁢∂μ⁡Gν,a⁢G⁢μb⁢μb⁢G⁢νc⁢νc−g__s⁢fsu3c,d,e⁢Gμ,a⁢Gα,b⁢G⁢μe⁢μe⁢G⁢αd⁢αd4
LagrangianQCD,interaction,expanded
g__s⁢λaA,B⁢uA,j&conjugate0;⁢uB,k+cA,j&conjugate0;⁢cB,k+tA,j&conjugate0;⁢tB,k+dA,j&conjugate0;⁢dB,k+sA,j&conjugate0;⁢sB,k+bA,j&conjugate0;⁢bB,k⁢Gμ,a⁢γ⁢μ⁢μj,k2−g__s⁢fsu3a,b,c⁢∂μ⁡Gν,a⁢G⁢μb⁢μb⁢G⁢νc⁢νc−g__s⁢fsu3c,d,e⁢Gμ,a⁢Gα,b⁢G⁢μe⁢μe⁢G⁢αd⁢αd4
The amplitude at tree level for the process with two incoming and two outgoing Up quarks (particle and antiparticle) exchanging a gluon
FeynmanDiagrams,incomingparticles=Up,conjugate⁡Up,outgoingparticles=Up,conjugate⁡Up,numberofloops=0,diagrams
−ⅈ⁢uuC,l⁡P→1⁢vuE,m⁡P→2&conjugate0;⁢uuF,n⁡P→3&conjugate0;⁢vuG,p⁡P→4⁢g__s2⁢λgF,G⁢γ⁢κ⁢κn,p⁢λfE,C⁢γ⁢β⁢βm,l⁢gβ,κ⁢δf,g⁢δ⁡−P__3⁢λ⁢λ−P__4⁢λ⁢λ+P__1⁢λ⁢λ+P__2⁢λ⁢λ16⁢π2⁢P__1σ+P__2σ⁢P__1⁢σ⁢σ+P__2⁢σ⁢σ+ⅈ⁢ε+ⅈ⁢uuC,l⁡P→1⁢vuE,m⁡P→2&conjugate0;⁢uuF,n⁡P→3&conjugate0;⁢vuG,p⁡P→4⁢g__s2⁢λgE,G⁢γ⁢κ⁢κm,p⁢λfF,C⁢γ⁢β⁢βn,l⁢gβ,κ⁢δf,g⁢δ⁡−P__3⁢λ⁢λ−P__4⁢λ⁢λ+P__1⁢λ⁢λ+P__2⁢λ⁢λ16⁢π2⁢P__1σ−P__3σ⁢P__1⁢σ⁢σ−P__3⁢σ⁢σ+ⅈ⁢ε
The Electro-Weak Lagrangian
The electroweak sector of the Standard Model Lagrangian is significantly more complicated
Lagrangianelectroweak
−𝔽μ,ν24−𝕎+μ,ν⁢𝕎−μ,ν2+mW2⁢W+μ⁢W−μ−ℤμ,ν24+mZ2⁢Zμ22+∂μ⁡Φ22−mΦ2⁢Φ22+∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__Lk−mf__L⁢f__Lj+∑f__L=νe,νμ,ντ⁡ⅈ⁢γμj,k⁢f__Lj&conjugate0;⁢∂μ⁡f__Lk+∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__QA,k−mf__Q⁢f__QA,j+g__e⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Aμ+g__w⁢γμj,k⁢δk,l+γ5k,l⁢I__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Ll+I__n⁢∑f__L=νe,νμ,ντ⁡f__Lj&conjugate0;⁢f__Ll+I__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,l+I__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,l−sin⁡θw2⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Zμcos⁡θw−g__w⁢2⁢γμj,k⁢δk,l+γ5k,l⁢∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D⁢f__UA,j&conjugate0;⁢f__DA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L1j⁡X&conjugate0;⁢f__L2l⁡X⁢W+μ+∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D&conjugate0;⁢f__DA,j&conjugate0;⁢f__UA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L2j⁡X&conjugate0;⁢f__L1l⁡X⁢W−μ2−g__w⁢mΦ2⁢Φ3+Φ48⁢mW4⁢mW+g__w⁢ΦmW+g__w2⁢Φ24⁢mW2⁢mW2⁢W+μ⁢W−μ+Zμ2⁢mZ22−ⅈ⁢g__w⁢𝕎+μ,ν⁢W−μ−W+μ⁢𝕎−μ,ν⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw+W−ν⁢W+μ⁢𝔽μ,ν⁢sin⁡θw−ℤμ,ν⁢cos⁡θw−g__w2⁢2⁢W+μ⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw2⁢2⁢W+ν⁢W−ν+Aν⁢sin⁡θw−Zν⁢cos⁡θw2+W+μ⁢W−ν+W+ν⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw24−g__w⁢∑f__L=e,μ,τ,νe,νμ,ντ⁡mf__L⁢f__Lj&conjugate0;⁢f__Lj+∑f__Q=u,c,t,d,s,b⁡mf__Q⁢f__QA,j&conjugate0;⁢f__QA,j⁢Φ2⁢mW
To decipher this result it is useful to see the structure of physically recognizable terms. For that purpose, you can use the keyword showterms
Lagrangianelectroweak,showterms
L__K+L__N+L__C+L__H+L__HV+L__WWV+L__WWVV+L__YwhereL__K=−𝔽μ,ν24−𝕎+μ,ν⁢𝕎−μ,ν2+mW2⁢W+μ⁢W−μ−ℤμ,ν24+mZ2⁢Zμ22+∂μ⁡Φ22−mΦ2⁢Φ22+∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__Lk−mf__L⁢f__Lj+∑f__L=νe,νμ,ντ⁡ⅈ⁢γμj,k⁢f__Lj&conjugate0;⁢∂μ⁡f__Lk+∑f__Q=u,c,t,d,s,b⁡f__QA,j&conjugate0;⁢ⅈ⁢γμj,k⁢∂μ⁡f__QA,k−mf__Q⁢f__QA,j,L__N=g__e⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Aμ+g__w⁢γμj,k⁢δk,l+γ5k,l⁢I__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Ll+I__n⁢∑f__L=νe,νμ,ντ⁡f__Lj&conjugate0;⁢f__Ll+I__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,l+I__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,l−sin⁡θw2⁢γμj,k⁢q__e⁢∑f__L=e,μ,τ⁡f__Lj&conjugate0;⁢f__Lk+q__u⁢∑f__Q=u,c,t⁡f__QA,j&conjugate0;⁢f__QA,k+q__d⁢∑f__Q=d,s,b⁡f__QA,j&conjugate0;⁢f__QA,k⁢Zμcos⁡θw,L__C=−g__w⁢2⁢γμj,k⁢δk,l+γ5k,l⁢∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D⁢f__UA,j&conjugate0;⁢f__DA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L1j⁡X&conjugate0;⁢f__L2l⁡X⁢W+μ+∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D&conjugate0;⁢f__DA,j&conjugate0;⁢f__UA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L2j⁡X&conjugate0;⁢f__L1l⁡X⁢W−μ2,L__H=−g__w⁢mΦ2⁢Φ3+Φ48⁢mW4⁢mW,L__HV=g__w⁢ΦmW+g__w2⁢Φ24⁢mW2⁢mW2⁢W+μ⁢W−μ+Zμ2⁢mZ22,L__WWV=−ⅈ⁢g__w⁢𝕎+μ,ν⁢W−μ−W+μ⁢𝕎−μ,ν⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw+W−ν⁢W+μ⁢𝔽μ,ν⁢sin⁡θw−ℤμ,ν⁢cos⁡θw,L__WWVV=−g__w2⁢2⁢W+μ⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw2⁢2⁢W+ν⁢W−ν+Aν⁢sin⁡θw−Zν⁢cos⁡θw2+W+μ⁢W−ν+W+ν⁢W−μ+Aμ⁢sin⁡θw−Zμ⁢cos⁡θw⁢Aν⁢sin⁡θw−Zν⁢cos⁡θw24,L__Y=−g__w⁢∑f__L=e,μ,τ,νe,νμ,ντ⁡mf__L⁢f__Lj&conjugate0;⁢f__Lj+∑f__Q=u,c,t,d,s,b⁡mf__Q⁢f__QA,j&conjugate0;⁢f__QA,j⁢Φ2⁢mW
In this result we see a sum of Lterms, and after 'where' there is a list of equations with the formulas represented by each Lterm. Take from the above, for instance, only the charged current LC term that involves interaction between the leptons and the corresponding neutrinos: you can do that with the mouse, copy and paste, or using the term= ... option of Lagrangian
Lagrangianelectroweak,term=LC
L__C=−g__w⁢2⁢δk,l+γ5k,l⁢∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D⁢f__UA,j&conjugate0;⁢f__DA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L1j⁡X&conjugate0;⁢f__L2l⁡X⁢W+μ+∑f__D=d,s,b⁡∑f__U=u,c,t⁡𝕄f__U,f__D&conjugate0;⁢f__DA,j&conjugate0;⁢f__UA,l+∑f__L=νe,e,νμ,μ,ντ,τ⁡f__L2j⁡X&conjugate0;⁢f__L1l⁡X⁢W−μ⁢γ⁢μ⁢μj,k2
The same term in expanded form, useful for computing scattering amplitudes
Lagrangianelectroweak,term=LC,expanded
L__C=−g__w⁢2⁢δk,l+γ5k,l⁢𝕄u,d⁢uA,j&conjugate0;⁢dA,l+𝕄c,d⁢cA,j&conjugate0;⁢dA,l+𝕄t,d⁢tA,j&conjugate0;⁢dA,l+𝕄u,s⁢uA,j&conjugate0;⁢sA,l+𝕄c,s⁢cA,j&conjugate0;⁢sA,l+𝕄t,s⁢tA,j&conjugate0;⁢sA,l+𝕄u,b⁢uA,j&conjugate0;⁢bA,l+𝕄c,b⁢cA,j&conjugate0;⁢bA,l+𝕄t,b⁢tA,j&conjugate0;⁢bA,l+νej&conjugate0;⁢el+νμj&conjugate0;⁢μl+ντj&conjugate0;⁢τl⁢W+μ+𝕄u,d&conjugate0;⁢dA,j&conjugate0;⁢uA,l+𝕄c,d&conjugate0;⁢dA,j&conjugate0;⁢cA,l+𝕄t,d&conjugate0;⁢dA,j&conjugate0;⁢tA,l+𝕄u,s&conjugate0;⁢sA,j&conjugate0;⁢uA,l+𝕄c,s&conjugate0;⁢sA,j&conjugate0;⁢cA,l+𝕄t,s&conjugate0;⁢sA,j&conjugate0;⁢tA,l+𝕄u,b&conjugate0;⁢bA,j&conjugate0;⁢uA,l+𝕄c,b&conjugate0;⁢bA,j&conjugate0;⁢cA,l+𝕄t,b&conjugate0;⁢bA,j&conjugate0;⁢tA,l+ej&conjugate0;⁢νel+μj&conjugate0;⁢νμl+τj&conjugate0;⁢ντl⁢W−μ⁢γ⁢μ⁢μj,k2
A process at tree level with a positron and electronic neutrino incoming and the antiparticle of the muon and a muon neutrino outgoing after exchanging a W boson
FeynmanDiagramsrhs⁡,incoming=conjugate⁡Electron,ElectronNeutrino,outgoing=conjugate⁡Muon,MuonNeutrino,numberofloops=0,diagrams
−ⅈ4⁢vem⁡P→1&conjugate0;⁢uνen⁡P→2⁢vμp⁡P→3⁢uνμq⁡P→4&conjugate0;⁢−ⅈ⁢2⁢g__w⁢γ5r,p⁢γ⁢α⁢αq,r2−ⅈ⁢2⁢g__w⁢γ⁢α⁢αq,p2⁢−ⅈ⁢2⁢g__w⁢γ5s,n⁢γ⁢ν⁢νm,s2−ⅈ⁢2⁢g__w⁢γ⁢ν⁢νm,n2⁢−gα,ν+P__1ν+P__2ν⁢P__1α+P__2αmW−2⁢δ⁡−P__3⁢β⁢β−P__4⁢β⁢β+P__1⁢β⁢β+P__2⁢β⁢βπ2⁢P__1κ+P__2κ⁢P__1⁢κ⁢κ+P__2⁢κ⁢κ−mW−2+ⅈ⁢ε
The term LHV of the electroweak Lagrangian contains the interaction between the Higgs and the Z and W bosons
Lagrangianelectroweak,term=LHV,interaction
L__HV=g__w⁢ΦmW+g__w2⁢Φ24⁢mW2⁢mW2⁢W+μ⁢W−⁢μ⁢μ+mZ2⁢Zμ⁢Z⁢μ⁢μ2
The probability density at one loop for a process with three Higgs incoming and outgoing: to omit the large - two pages - algebraic result containing Feynman integrals, end the input line with ":", or remove that ending to see and manipulate the integrals. Note this result involves Feynman diagrams with two, three, four, five and six vertices. New in Maple 2023 are the diagrams with more than four vertices.
FeynmanDiagramsrhs,incoming=HiggsBoson,HiggsBoson,HiggsBoson,outgoing=HiggsBoson,HiggsBoson,HiggsBoson,numberofloops=1,diagrams,output=probabilitydensity: