Extracting light-cone wave functions from covariant amplitudes: a detailed study in scalar field theory
arXiv:2512.22345 · doi:10.1103/63qq-rx6g
The paper proposes a formula that converts covariant off‑shell amplitudes into light‑cone wave functions for scalar field theory, verifies it at one‑loop order, and shows it simplifies calculations compared to traditional light‑cone quantization.
Abstract
We propose a conjectured formula that systematically maps covariant off-shell amplitudes to light-cone wave functions in scalar field theory. Through an explicit comparison at one-loop accuracy, we establish its equivalence to the light-cone perturbation theory series, thereby validating the conjecture at this order. Applying this formula, we efficiently re-derive wave functions from known covariant amplitudes, bypassing both the conceptual complexities of light-cone quantization and the technical challenges of perturbative calculations in this framework. In addition to simplifying computations, this approach opens new avenues for applications in gauge theories and deeper explorations of the fundamental equivalence between covariant and light-cone quantization.
21 pages. v2: Revised for clarity and corrected minor issues; results unchanged. v3: Minor refinements. Accepted for publication in Phys.Rev.D