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arXiv · 2402.14839

Exact Evaluation and extrapolation of the divergent expansion for the Heisenberg-Euler Lagrangian II: Non-alternating Case

Christian D. Tica·Eric A. Galapon
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Abstract

We applied the method of finite-part integration [Galapon E.A Proc.R.Soc A 473, 20160567(2017)] to evaluate in closed-form the exact one-loop integral representations of the Heisenberg-Euler Lagrangian from QED for a constant electric field and electric-like self-dual background. We also devise a prescription based on the finite-part integration of the Cauchy principal value integral to sum and extrapolate the non-alternating divergent weak-field expansions of the Heisenberg-Euler Lagrangians to recover the non-perturbative Schwinger effect well into the strong field limit.

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Christian D. Tica, Eric A. Galapon. 2024-02-19. Exact Evaluation and extrapolation of the divergent expansion for the Heisenberg-Euler Lagrangian II: Non-alternating Case. https://arxiv.org/abs/2402.14839

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