Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedverified 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 ideal PEC boundary condition is not preserved by a vacuum duality quarter-turn

Physical scope

A smooth source-free vacuum field in a half-space with an ideal perfect-electric-conductor boundary condition imposed as model data. The calculation concerns that boundary condition only; it makes no claim about finite conductivity or measurements.

Example

On Ω={(x1,x2,x3):x3>0}, consider the constant vacuum field E=0 and B=B0(1,0,0), where B0≠0 has units T. Let Π={x3=0}, with unit normal n=(0,0,1). The constant fields are understood with their continuous traces on Π. In this example, a perfect-electric-conductor (PEC) boundary means the ideal boundary model imposing E∥=E−(E⋅n)n=0 on Π; this condition is imposed as model data and no finite-conductivity claim is made. For θ=π/2, the vacuum duality rotation Fθ=⋆ηF has electric field Eθ=−cB0(1,0,0), which is nonzero and parallel to Π. Thus the source-free vacuum duality rotation does not preserve this same PEC boundary condition.

Facts & Assumptions

Given: The half-space, plane, normal, constant field, ideal PEC boundary condition, and quarter-turn angle in the Example.

[A1]

The PEC condition used here is exactly E_parallel = E - (E dot n)n = 0 on Pi. It is an ideal boundary assumption, not a material constitutive law.

[F1]

Excitation and free-current forms defines F=B−dt∧E and fixes F0i=−Ei/c.

[F2]

Vacuum duality and its domain states that the quarter-turn F↦⋆ηF maps a source-free vacuum solution to another source-free vacuum solution.

[F3]

Lorentzian Hodge star and periods gives ⋆η(dx2∧dx3)=dx0∧dx1 in the fixed (−+++) orientation.

[F5]

The microscopic vacuum Maxwell equations: smooth and weak branches adopts the four smooth vacuum Maxwell equations and excludes magnetic-source terms.

Verification

1.1A1F5givenalgebra

The fields are constant, so all their spatial and time derivatives vanish. With P=M=0 and ρ=J=0, they satisfy the four vacuum Maxwell equations on Ω by [F5]. The original tangential electric field is E∥=0, so it satisfies the imposed PEC condition [A1].

2.1A1F1F2F3F4givenstep 1.1algebra∎

The field form is F=B0dx2∧dx3. By [F3], ⋆ηF=B0dx0∧dx1=cB0dt∧dx1. Comparing with the defining form Bθ−dt∧Eθ in [F1] gives Eθ=−cB0(1,0,0). Since Eθ⋅n=0, its tangential component equals Eθ and is nonzero. Hence the rotated vacuum solution from [F2] fails the same PEC boundary condition. The unit cB0 is V m−1, as required for an electric field by [F4].

Depends on

Dependency tree · 2 levels

Sources