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Nontrivial zeros of the QED β-function (ultraviolet fixed points)

Determine whether the Gell-Mann–Low β-function of quantum electrodynamics possesses a nontrivial zero at finite coupling, thereby establishing or excluding the existence of a nontrivial ultraviolet fixed point for QED beyond perturbation theory.

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Background

Gell-Mann and Low introduced the renormalisation group framework and highlighted the special role of zeros of the β-function as fixed points that govern high-energy behavior. They conjectured that the fine structure constant might correspond to such a fixed point.

However, beyond perturbation theory, the global behavior of the QED β-function is unknown, and in particular it is unknown whether it has any nontrivial (nonzero) zeros. Resolving this would clarify the ultraviolet completeness or triviality of QED.

References

Obviously, as long as perturbation theory is our only guide, we cannot say anything about the properties of the β(λ) for arbitrary λ and we do not know whether it has any non-trivial zeros.

From Many Models to ONE THEORY (2501.10233 - Iliopoulos, 17 Jan 2025) in Subsection: The renormalisation group