All-Plus QED Wavefunctions in de Sitter Space

Song He; Jiajie Mei; Yuyu Mo

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arXiv · 2609.29356

All-Plus QED Wavefunctions in de Sitter Space

Song He·Jiajie Mei·Yuyu Mo

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Abstract

We present a compact all-multiplicity formula for tree-level late-time wavefunction coefficients of scalar QED in four-dimensional de Sitter space, with a conformally coupled charged scalar pair and positive-helicity photons. It combines lower-point coefficients at shifted scalar momenta with a spinor-helicity term proportional to the total energy. The flat-space amplitudes vanish for two or more photons, yet the de Sitter coefficients remain nonzero. These zeros enforce cancellations of the total-energy residue and, through factorization, of proper partial-energy residues involving multi-photon subamplitudes. Using a common-reference construction, we derive an exact lower-point recursion from Abelian Ward identities. Conformal symmetry provides an independent check: the partition sum solves the inhomogeneous Ward identity, while the total-energy term is a homogeneous solution. We also outline an analogous recursion in massless fermionic QED.

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Song He, Jiajie Mei, Yuyu Mo. 2026-09-24. All-Plus QED Wavefunctions in de Sitter Space. https://arxiv.org/abs/2609.29356

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