The Vehicle Made of Light: Gravitational Response of a Self-Sustained Wave Shell Transporting Massive Internal Cargo (Light-Vehicle Program, Paper I)

Abstract

A research program proposes a vehicle whose shell is itself a self-sustained nonlinear wave propagating at the speed of light c, carrying massive internal cargo (a passenger and a sound device) whose internal physics is ordinary. Earlier sections of the program established the kinematic machinery (a singular projection under which every internal point is externally displaced at exactly X = cT) and closed the transport cycle internally: sound loaded at rest inside the shell is delivered while externally propagating at c. An independent conservation audit books the compound a strictly positive invariant mass, in open tension with the exact-null projection. This paper executes the program's proposed decisive test, Section 90: the gravitational sector. We construct the coupled field action whose Euler-Lagrange equations reproduce the model's shell and matter equations, derive the canonical stress-energy tensor, prove the energy decomposition E_tot = cP_T + H_int, and show that the pullback of the spacetime metric through the projection is identically null (a rank-one null dyadic whose kernel N = (1, -c) is precisely where the audited mass resides). Under a minimal embedding postulate (shape-locked null transport), the exterior field is an Aichelburg-Sexl shock of strength E_tot = cP_T + H_int, not of the radiometric energy alone. The program thereby acquires its first quantitative differential prediction - lensing sees the cargo: the excess deflection of a test ray, dTheta = 4G H_int / (c^4 b), vanishes for every wall-free null configuration carrying no internal sector. We quantify the prediction, state the timelike-books variant (a static 1/r tail), and assess what the model has paid and what it still owes standard physics. Keywords: special relativity, stress-energy tensor, nonlinear field theory, Aichelburg-Sexl metric, wave shells, gravitational deflection, mass-energy equivalence, theoretical physics.