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.
Electric amplitude has a longitudinal component
A conditional bulk plane-wave example in a homogeneous lossless uniaxial dielectric with positive principal permittivities, positive scalar permeability, a real nonzero wavevector on the extraordinary sheet, and nonzero transverse and axial wavevector components. Physical interpretation is restricted to a declared finite positive-frequency band of effective phase response; the algebraic example holds for every positive frequency. It makes no interface, finite-beam or empirical claim.
Example
Let with and , and let . Fix and real with on the extraordinary sheet . Choose in and set the displacement amplitude and electric amplitude . Then but . Thus the extraordinary electric amplitude is not orthogonal to the wavevector even though the displacement amplitude is.
The algebraic example holds for every . For physical interpretation, declare a finite angular-frequency band with , in , and use the constant-coefficient model only for , as in the supplying uniaxial classification.
Statement references
Facts & Assumptions
Given: The positive uniaxial coefficients, , , and the extraordinary dispersion relation stated above, all in SI units.
The extraordinary sheet and its nonzero source-free polarization modes are those of Ordinary and extraordinary sheets; the displacement amplitude is in the same model.
Verification
Since , the diagonal matrix is invertible, so is defined and nonzero. Direct contraction gives and by the nonzero-component and unequal-permittivity hypotheses.
The extraordinary dispersion relation gives . Hence the and components of are and , while the component is zero. Thus , so is an extraordinary symbol mode and the longitudinal-component claim follows.