Fakeons and Lee-Wick models - Archive ouverte HAL Access content directly
Journal Articles Journal of High Energy Physics Year : 2018

Fakeons and Lee-Wick models

Fauxons et modèles de Lee et Wick

Abstract

The "fakeon" is a fake degree of freedom, i.e. a degree of freedom that does not belong to the physical spectrum, but propagates inside the Feynman diagrams. Fakeons can be used to make higher-derivative theories unitary. Moreover, they help us clarify how the Lee-Wick models work. In this paper we study the fakeon models, that is to say the theories that contain fake and physical degrees of freedom. We formulate them by (nonanalytically) Wick rotating their Euclidean versions. We investigate the properties of arbitrary Feynman diagrams and, among other things, prove that the fakeon models are perturbatively unitary to all orders. If standard power counting constraints are fulfilled, the models are also renormalizable. The $S$ matrix is regionwise analytic. The amplitudes can be continued from the Euclidean region to the other regions by means of an unambiguous, but nonanalytic, operation, called average continuation. We compute the average continuation of typical amplitudes in four, three and two dimensions and show that its predictions agree with those of the nonanalytic Wick rotation. By reconciling renormalizability and unitarity in higher-derivativderivative theories, the fakeon models are good candidates to explain quantum gravity.
Fichier principal
Vignette du fichier
Fakeons.pdf (569.98 Ko) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-01900285 , version 1 (21-10-2018)

Identifiers

Cite

Damiano Anselmi. Fakeons and Lee-Wick models. Journal of High Energy Physics, 2018, 2018 (2), ⟨10.1007/JHEP02(2018)141⟩. ⟨hal-01900285⟩

Collections

INSMI TDS-MACS
113 View
269 Download

Altmetric

Share

Gmail Facebook X LinkedIn More