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arXiv · 2606.29318

On Padmanabhan's duality invariance and the quantum of length

P. Fernandez de Cordoba·J. M. Isidro·A. Pereira Garcia
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Abstract

We provide a field-theoretic construction of Padmanabhan's duality-invariant Feynman propagator for a massive point particle in Euclidean space $\mathbb{R}^D$. Padmanabhan's propagator includes quantum-gravity effects due to the existence of a quantum of length $\ell$. Including $O(\ell^2)$ corrections, the corresponding field-theory model turns out to be a free, massive scalar defined in $\mathbb{R}^{D+2}$. The two additional dimensions with respect to the original $\mathbb{R}^D$ provide the necessary room, so to speak, for quantum-gravity fluctuations.

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P. Fernandez de Cordoba, J. M. Isidro, A. Pereira Garcia. 2026-06-28. On Padmanabhan's duality invariance and the quantum of length. https://arxiv.org/abs/2606.29318

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