Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedprecheck passverified 2026-10-22 (gpt-6.1-sol)
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.

An oblique plane wave with a nonzero longitudinal electric component

Physical scope

Exact plane-wave example in the smooth, source-free vacuum Maxwell model and the propagating cone of the ideal angular-spectrum model. It illustrates the longitudinal component required by Maxwell's equations for its specified transverse polarization; it asserts no measured field, focal apparatus, or torque.

Example

Let 0<κ≤δk0, q=(κ,0), kz:=k02−κ2, and choose a real E0≠0 in V m−1. Put e:=(E0,0,−κE0/kz),b:=(0,k02E0ωkz,0),ϕ(x,t):=κx+kzz−ωt. The real fields E(x,t):=Re⁡(eeiϕ(x,t)) and B(x,t):=Re⁡(beiϕ(x,t)) are an exact, forward, source-free vacuum plane-wave mode. In particular, ez=−κE0k02−κ2≠0,∣ez∣∣E0∣=κk02−κ2≤δ1−δ2. Thus setting ez=0 while keeping this transverse amplitude would not give an exact Maxwell mode.

Facts & Assumptions

Given: A fixed SI laboratory chart, c>0, ω>0, k0=ω/c, 0<δ<1, 0<κ≤δk0, and real E0≠0 in V m−1.

[F2]

The plane-wave convention uses the real part of complex amplitudes times ei(K⋅x−ωt). Complex plane-wave fields: real parts of complex exponentials

[A1]

The adopted smooth source-free vacuum Maxwell equations, with ρ=0 and J=0, are div⁡E=div⁡B=0, curl⁡E=−∂tB, and curl⁡B=c−2∂tE; ρ and J are the charge and current densities of the source definition, and divergence and curl are the coordinate operators of the fixed spatial chart. The microscopic vacuum Maxwell equations: smooth and weak branches Charge parameter, frame charge and current densities, volume charge and flux, and the four-current Divergence and curl of a C1 vector field

[F4]

For an exact mode with these q,kz, the longitudinal relation and cone bound are as stated in the paraxial error theorem. Paraxial phase and longitudinal-field bounds

Verification

1.1givenF1algebra

Since κ≤δk0<k0, kz=k02−κ2 is positive. The definitions give κ2+kz2=k02, κE0+kzez=0, and ωby=k02E0/kz. Thus K=(κ,0,kz) is a forward wavevector of length k0, and e is transverse to it.

2.1step 1.1F1F2F3A1algebra

By [F3], for each spatial coordinate xj, ∂xjE=Re⁡(iKje eiϕ) componentwise, and ∂tE=Re⁡(−iωe eiϕ); the same formulas hold with B,b in place of E,e. From [step 1.1], K⋅e=κE0+kzez=0,K⋅b=0, K×e=(0,kzE0−κez,0)=(0,k02E0kz,0)=ωb, and K×b=(−kzby,0,κby)=(−k02E0ω,0,κk02E0ωkz)=−ωc2e, where the last equality uses k0=ω/c. Summing the spatial derivatives therefore yields div⁡E=Re⁡(i(K⋅e)eiϕ)=0,div⁡B=Re⁡(i(K⋅b)eiϕ)=0, curl⁡E=Re⁡(i(K×e)eiϕ)=−∂tB,curl⁡B=Re⁡(i(K×b)eiϕ)=c−2∂tE. Thus all four source-free Maxwell equations in [A1] hold pointwise, so these real fields are an exact mode.

3.1givenstep 1.1F4algebra∎

The constructed transverse amplitude is (E0,0). Applying [F4] gives ez=−q⋅e⊥/kz=−κE0/kz and ∣ez∣/∣E0∣≤δ/1−δ2. Since κ>0, E0≠0, and kz>0, ez≠0. Hence the alternative ez=0 with this same transverse amplitude is incompatible with source-free Maxwell transversality.

Remarks

For the illustrative case δ=3/4 and κ/k0=1/2, the normalized x-z projections are K/k0=(1/2,3/2) and e/E0=(1,−1/3); their dot product is zero. The arrows use these separate dimensionless normalizations, and the figure is schematic only. The Maxwell verification is the component proof in step 2.1, not the drawing.

\begin{tikzpicture}[x=2.5cm,y=2cm,>=stealth]
  \draw[->] (-0.12,0) -- (1.25,0) node[right] {$x$ component};
  \draw[->] (0,-0.8) -- (0,1.15) node[above] {$z$ component};
  \draw[dashed,gray] (0,0) -- (0.5,0);
  \draw[dashed,gray] (0.5,0) -- (0.5,{sqrt(3)/2});
  \draw[very thick,->] (0,0) -- (0.5,{sqrt(3)/2})
    node[above right] {$\mathbf K/k_0$};
  \draw[very thick,->,blue] (0,0) -- (1,{-1/sqrt(3)})
    node[below right] {$\mathbf e/E_0$};
  \node[below] at (0.5,0) {$\kappa/k_0=1/2$};
  \node[right] at (0.5,0.53) {$k_z/k_0=\sqrt3/2$};
\end{tikzpicture}

Depends on

Dependency tree · 2 levels

Sources