Causality and unitarity via the tree-loop duality relation
Sign Up to like & getrecommendations! Published in 2017 at "Journal of High Energy Physics"
DOI: 10.1007/jhep05(2017)148
Abstract: A bstractThe tree-loop duality relation is used as a starting point to derive the constraints of causality and unitarity. Specifically, the Bogoliubov causality condition is ab initio derived at the individual graph level. It leads… read more here.
Keywords: tree loop; loop duality; relation; causality ... See more keywords
$S$ -matrix unitarity and renormalizability in higher-derivative theories
Sign Up to like & getrecommendations! Published in 2019 at "Progress of Theoretical and Experimental Physics"
DOI: 10.1093/ptep/ptz084
Abstract: We investigate the relation between $S$-matrix unitarity ($SS^\dagger=1$) and renormalizability in theories with negative-norm states. The relation has been confirmed in many field theories, including gauge theories and Einstein gravity, by analyzing the unitarity bound,… read more here.
Keywords: matrix unitarity; unitarity renormalizability; unitarity bound; unitarity ... See more keywords
Perturbative Higgs coupling CP violation, unitarity, and phenomenology
Sign Up to like & getrecommendations! Published in 2017 at "Physical Review D"
DOI: 10.1103/physrevd.95.015018
Abstract: Perturbative probability conservation provides a strong constraint on the presence of new interactions of the Higgs boson. In this work we consider CP-violating Higgs interactions in conjunction with unitarity constraints in the gauge-Higgs and fermion-Higgs… read more here.
Keywords: higgs; higgs coupling; coupling violation; unitarity ... See more keywords
Secret loss of unitarity due to the classical background
Sign Up to like & getrecommendations! Published in 2017 at "Physical Review D"
DOI: 10.1103/physrevd.96.025005
Abstract: We show that a quantum subsystem can become significantly entangled with a classical background through a process with little or none semi-classical back-reactions. We study two quantum harmonic oscillators coupled to each other in a… read more here.
Keywords: classical background; unitarity due; secret loss; loss unitarity ... See more keywords