Alphabeta Math
ExampleConstruction: AI-adaptedVerification: AI-adaptedPipeline-generatedprecheck pass
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

The harmonic model worked through: an explicit complete integral, its characteristic motion, and the action-angle chart with I=∮p dx and period-one frequency 1/T

Physical scope

A worked instance of the Hamilton-Jacobi and action-angle items inside the declared scalar harmonic model, identified with the generalized-coordinate presentation of the explicit straight-line immersion into a three-dimensional force model: for one label of mass m>0 and spring constant k>0, the explicit family S is a complete integral of the model's Hamilton-Jacobi equation wherever sin⁡(ωt)≠0; its characteristic curves are the harmonic motions with β=Sα constant; and the explicit chart (θ,I) is canonical with H=I/T, I˙=0, θ˙=1/T and I=∮p dx, in the period-one convention, with the radian rescaling recovering the sources' chart. The example asserts no measured value, no claim that a real oscillator realizes the model, and no global extension of S across the conjugate times ωt∈πZ.

Example

Adopt the harmonic model of The harmonic (linear restoring) model: a declared linear force law with parameter k>0: one label of mass m>0 on R with spring constant k>0, force law F(x)=−kx, potential U(x)=12kx2 and no residual force. For the CM12-CM14 presentation interfaces, declare the ambient one-label model on Qamb=R3 with mass operator mI3, time window R, potential Uamb(y)=ky12/2, d=0 and smooth force Famb(y,v)=(−ky1,0,0) (Adopted force model: force maps, the equation of motion, additive composition of force contributions and frame covariance, Potential presentations of a force model, potential and mechanical energy, closed versus exact force fields, local potentials and equipotential level sets, The action functional of a force model with a potential presentation: the mechanical Lagrangian, its chart instance and its dimensions). The generalized-coordinate map X:R→Qamb, X(x)=(x,0,0) is a smooth immersion with length-valued coordinate x, G=DXTmI3DX=m and substituted potential kx2/2 (Generalized-coordinate maps of the model, the substituted Lagrangian, the kinetic metric and generalized forces). Thus its chart Hamiltonian H~ of The Hamiltonian of a hyperregular potential presentation: the Legendre transform of the mechanical Lagrangian, its domain and its dimensions clause (b) is exactly the scalar Hamiltonian below; write it as H. A scalar harmonic motion reconstructs an ambient motion X∘x since the longitudinal equation is mx′′=−kx and both transverse equations are 0=0. Write

ω:=km>0,T:=2πω,

so that U(x)=12mω2x2 and the branch Hamiltonian in the generalized-coordinate chart is

H(x,p)=p22m+mω22x2

(Every potential presentation is hyperregular in its charts, with inverse branch v=M−1p (or G(q)−1p) and the explicit kinetic-plus-potential Hamiltonian, The Hamiltonian of a hyperregular potential presentation: the Legendre transform of the mechanical Lagrangian, its domain and its dimensions), with [H]=μℓ2τ−2 (Dimensions and SI unit conventions of the non-relativistic classical mechanics framework). On the open set

V:={(t,x,α)∈R3:sin⁡(ωt)≠0}

define

S(t,x,α):=mω2[(x2+α2)cot⁡(ωt)−2xα csc⁡(ωt)]. The example checks the following claims of this page on this instance.

  1. (complete integral) S is of class C∞ on V and solves the model's Hamilton-Jacobi equation St+H(x,Sx)=0 on V; the mixed derivative is Sxα=−mω csc⁡(ωt), so S is a complete integral of the model's Hamilton-Jacobi equation at every point of V (The Hamilton-Jacobi equation of a declared potential presentation: the class of action-dimension functions S with St+H(t,q,Sq)=0 in one momentum chart, A complete integral of the model's Hamilton-Jacobi equation: nondegenerate mixed derivative, momentum map and Jacobi constants).

  2. (characteristics) for every (t0,x0,α0)∈V and every real β, the curve x(t)=α0cos⁡(ωt)−βmωsin⁡(ωt) satisfies Sα(t,x(t),α0)=β, and with p(t):=Sx(t,x(t),α0) the pair (x,p) solves x′=Hp, p′=−Hx on every interval on which sin⁡(ωt)≠0; hence x is a motion of the harmonic model with p=mx′ and Sα is constant along it (A complete integral of the model's Hamilton-Jacobi equation produces chart Hamiltonian characteristics, Jacobi constants and local canonical (β,α) labels).

  3. (action-angle chart) the map (θ,I)⟼(x,p)=(Iπmω sin⁡(2πθ), Imωπ cos⁡(2πθ))

    for I>0 and θ∈R/Z is a C∞ parametrization of the punctured phase plane; local real lifts of θ give charts with {x,p}=1 for the presentation's bracket, i.e. a canonical chart of Canonical coordinates and the canonical form of the two-form for a potential presentation: the coordinate expression ω=∑a=1mdθa∧dθm+a with m the chart's half-dimension, and the model's own momentum charts with ωform=dθ∧dI in the period-one convention of Action and angle coordinates, and in it H=h(I)=IT, so that every motion satisfies I˙=0, θ˙=1/T, by the canonical Hamiltonian field of The Hamiltonian field of a phase function for a potential presentation: the unique field Xf with ιXfω=df, and XH=(Hp,−Hx) for the branch Hamiltonian clause (a).

  4. (action normalization) the action coordinate is the period integral I=∮p dx=∫0Tp(t) x′(t) dt along one period of the oscillator motion, in the period-one normalization discussed in the remark of Action-angle coordinates of a completely integrable presentation: period-one angles, action coordinates, H=h(I) and linear motion on the tori.

  5. (radian convention) with θrad:=2πθ and Irad:=I/(2π) the chart becomes x=2Irad/(mω) sin⁡θrad, p=2Iradmω cos⁡θrad with H=ωIrad and θ˙rad=ω, which is the radian chart of the sources (Period-one to radian action-angle rescaling: θrad=2πθ and Irad=I/(2π) preserve ω).

All data m,k are declared model parameters; the example asserts no measured value and no claim about a real oscillator.

Facts & Assumptions

Given: The harmonic model data m>0, k>0, the ambient potential presentation and immersion X just declared, the constants ω,T, the Hamiltonian H, the open set V and the function S displayed above.

[L1]

Model and Hamiltonian (The harmonic (linear restoring) model: a declared linear force law with parameter k>0, The motions of the harmonic model are the sinusoids Acos⁡(ω(t−t0))+Bsin⁡(ω(t−t0)): amplitude and phase, the least period, the conserved energy kR2/2 and the elliptical phase curves, Every potential presentation is hyperregular in its charts, with inverse branch v=M−1p (or G(q)−1p) and the explicit kinetic-plus-potential Hamiltonian, The Hamiltonian of a hyperregular potential presentation: the Legendre transform of the mechanical Lagrangian, its domain and its dimensions, The associated first-order system, motions, maximal motions and the Newtonian flow of a force model, Generalized-coordinate maps of the model, the substituted Lagrangian, the kinetic metric and generalized forces): scalar motions of the model are the solutions of mx′′=−kx, and are exactly the curves x(t)=Acos⁡(ω(t−t0))+Bsin⁡(ω(t−t0)) with reals A,B; the inverse Legendre branch is (x,p)↦p/m, equivalently p=mx′, and the branch Hamiltonian is the displayed H. The least positive period of x is T when (A,B)≠(0,0), by clause 3 of The motions of the harmonic model are the sinusoids Acos⁡(ω(t−t0))+Bsin⁡(ω(t−t0)): amplitude and phase, the least period, the conserved energy kR2/2 and the elliptical phase curves.

[L2]

Calculus (Ck Euclidean maps and diffeomorphisms, Directional derivatives and partial derivatives of a map U⊆Rm→Rn, The Jacobian matrix of partial derivatives and the gradient in the scalar-valued case, The derivatives of sine and cosine are cosine and minus sine, The chain rule, in one line from Carathéodory: if g is differentiable at c and f is differentiable at g(c), then f∘g is differentiable at c with (f∘g)′(c)=f′(g(c)) g′(c), Sums, scalar multiples, products and quotients: (f+g)′(c)=f′(c)+g′(c), (αf)′(c)=αf′(c), (fg)′(c)=f′(c)g(c)+f(c)g′(c), and (f/g)′(c)=(f′(c)g(c)−f(c)g′(c))/g(c)2 when g(c)≠0, Double-angle and quadratic power-reduction identities, The zero sets of sine and cosine and the least positive common period 2 pi, Parity and the Pythagorean identity for sine and cosine, If f:[a,b]→Rm is differentiable with integrable f′ then ∫abf′=f(b)−f(a); and a bounded derivative makes f Lipschitz, The lower and upper Darboux integrals of a bounded f on [a,b] as sup⁡PL(f,P) and inf⁡PU(f,P), Darboux integrability as their equality, and the notation ∫abf, Intervals of R: the nine order-convex forms, nondegeneracy, and length): the derivatives (sin⁡)′=cos⁡, (cos⁡)′=−sin⁡, (cot⁡)′=−csc⁡2, (csc⁡)′=−csc⁡cot⁡ hold wherever the functions are defined; the chain rule and the algebra of derivatives apply; the power-reduction identity cos⁡2u=(1+cos⁡2u)/2 and the Pythagorean identity sin⁡2u+cos⁡2u=1 hold; sin⁡(kπ)=0 for integers k; and a continuous u:[a,b]→R with a primitive W satisfies ∫abu=W(b)−W(a).

[L4]

Characteristics theorem (A complete integral of the model's Hamilton-Jacobi equation produces chart Hamiltonian characteristics, Jacobi constants and local canonical (β,α) labels): a complete integral S produces curves with p=Sx solving the Hamilton equations and with β=Sα constant.

[L5]

Canonical chart and field (Canonical coordinates and the canonical form of the two-form for a potential presentation: the coordinate expression ω=∑a=1mdθa∧dθm+a with m the chart's half-dimension, and the model's own momentum charts, The Hamiltonian field of a phase function for a potential presentation: the unique field Xf with ιXfω=df, and XH=(Hp,−Hx) for the branch Hamiltonian clause (a), Action and angle coordinates, The Euclidean inverse function theorem): a smooth coordinate map with nonzero Jacobian has smooth local inverses. In coordinates (θ,I) with two-form dθ∧dI, the defining equation ιXHωform=dH reads θ˙=HI, I˙=−Hθ. The radian rescaling preserves the two-form and transforms the Hamiltonian as h~(Irad)=h(2πIrad).

Verification

technique · direct; compute the partial derivatives, verify the Hamilton-Jacobi equation and the characteristic equations by substitution, check the Poisson bracket of the explicit chart, and evaluate the period integral
1.1L2L3givenalgebra

Derivatives of S: with c:=cos⁡(ωt) and s:=sin⁡(ωt), [L2] gives Sx=mω(xcot⁡(ωt)−αcsc⁡(ωt)) and St=mω22[−(x2+α2)csc⁡2(ωt)+2xα csc⁡(ωt)cot⁡(ωt)]. Substituting p=Sx into H, St+H(x,Sx)=mω22[−(x2+α2)csc⁡2+2xαcsc⁡cot⁡+(xcot⁡−αcsc⁡)2+x2]=mω22x2(−csc⁡2+cot⁡2+1)=0, because cot⁡2−csc⁡2=−1; and Sxα=−mω csc⁡(ωt)≠0 on V. Hence S is a C∞ complete integral of the model's Hamilton-Jacobi equation at every point of V, which is claim 1. Dimensions: [mωx2]=μτ−1ℓ2=[S].

2.1L1L2L4step 1.1algebra

The characteristic motion: put x(t):=α0cos⁡(ωt)−β(mω)−1sin⁡(ωt) and p(t):=Sx(t,x(t),α0). By [L2], x′(t)=−α0ωsin⁡(ωt)−βm−1cos⁡(ωt) and p(t)m=ω[x(t)cs−α01s]=ω[(α0c−βmωs)cs−α0s]=−ωα0s−βmc=x′(t), using α0(c2−1)/s=−α0s, so p=mx′ and x′=Hp=p/m, and p′(t)=−mω2α0c+βωs=−mω2x(t)=−Hx. For the constants, differentiating the displayed S in α gives Sα(t,x,α)=mω(αcot⁡(ωt)−xcsc⁡(ωt)), so Sα(t,x(t),α0)=mω[α0cot⁡(ωt)−(α0c−βmωs)csc⁡(ωt)]=mωα0(cot⁡−c csc⁡)+β=β, since cot⁡u−cos⁡u csc⁡u=0. Hence the characteristic curve lies on the level set Sα=β, it is a motion of the model with p=mx′ by [L1], and β=Sα is constant along it, which is claim 2.

3.1L2L5step 2.1algebra

The canonical chart: write x=I/(πmω) sin⁡(2πθ) and p=Imω/π cos⁡(2πθ); by [L2], xθpI−xIpθ=cos⁡2(2πθ)+sin⁡2(2πθ)=1, the computation being: xθ=2πI/(πmω)cos⁡, pI=12mω/π I−1/2cos⁡ give xθpI=cos⁡2; and xI=12(πmωI)−1/2sin⁡, pθ=−2πImω/πsin⁡ give xIpθ=−sin⁡2. The energy fixes I=2πH/ω>0, and the normalized pair (xπmω/I,pπ/(Imω)) fixes θ modulo one, so the parametrization is bijective onto the punctured phase plane; the nonzero Jacobian makes its inverse smooth in local angle lifts. Hence {x,p}=1 in the chart, i.e. the coordinates are canonical for the presentation's bracket and ωform=dθ∧dI. Substituting into H, H=p22m+mω22x2=Iω2π(cos⁡2+sin⁡2)=Iω2π=IT=h(I). Writing XH=a∂θ+b∂I, contraction gives a dI−b dθ=dH=T−1dI, so a=1/T, b=0 by [L5]. Hence I˙=0 and θ˙=1/T along the scalar harmonic motions, which is claim 3.

4.1L2step 3.1algebra

The period integral: parametrize the motion of step 3.1 with I>0, θ0=0 by x(t)=Asin⁡(ωt), A:=I/(πmω), so that p(t)=mx′(t)=mAωcos⁡(ωt) and the least positive period is T by [L1]. Then by [L2], ∮p dx=∫0Tp(t)x′(t) dt=mA2ω2∫0Tcos⁡2(ωt) dt=mA2ω2⋅T2=mA2ωπ=I, because cos⁡2(ωt)=(1+cos⁡2ωt)/2, the integral of cos⁡(2ωt) over [0,T] vanishes being an increment of sin⁡(2ωt)/(2ω) at sin⁡(2πk)=0, and mA2ωπ=mIπmωωπ=I. This is claim 4.

4.2L5step 3.1algebra

Radian rescaling: the map [u]↦[2πu] from R/Z to R/(2πZ) is a smooth bijection with smooth inverse [v]↦[v/(2π)], as checked in local real lifts. Thus θrad=2πθ and Irad=I/(2π) satisfy dθrad∧dIrad=(2π)dθ∧dI/(2π)=dθ∧dI and keep the two-form and give H=h(2πIrad)=2πIrad/T=ωIrad and θ˙rad=2πθ˙=2π/T=ω; inverting the rescaling in the chart of step 3.1 gives x=2Irad/(mω)sin⁡θrad and p=2Iradmωcos⁡θrad, the source's chart. This is claim 5.

5.1step 1.1step 2.1step 3.1step 4.1step 4.2∎

Claims 1-5 are verified by steps 1.1, 2.1, 3.1, 4.1 and 4.2 respectively; the example is verified.

Remarks

  • Where the construction breaks. The family S is defined only for sin⁡(ωt)≠0, and the mixed derivative Sxα=−mωcsc⁡(ωt) is unbounded as ωt→πZ; the complete integral is a local object between the conjugate times of the oscillator and is not continued across them. The companion example computes the focusing of the characteristic family at those times.

  • No empirical content. The oscillator data are declared model parameters, and the displayed identities are statements about the model; no measured frequency, amplitude or period is asserted.

Depends on

Dependency tree · 2 levels

Sources