摘要
We consider the positivity bounds on dimension-8 four-electron operators and study two related phenomenological aspects at future lepton colliders.First,if positivity is violated,probing such violations will revolutionize our understanding of the fundamental pillars of quantum field theory and the S-matrix theory.We observe that positivity violation at scales of 1-10 TeV can potentially be probed at future lepton colliders even if one assumes that dimension-6 operators are also present.Second,the positive nature of the dimension-8 parameter space often allows us to either directly infer the existence of UV-scale particles together with their quantum numbers or exclude them up to certain scales in a model-independent way.In particular,dimension-8 positivity plays an important role in the test of the Standard Model.If no deviations from the Standard Model are observed,it allows for simultaneous exclusion limits on all kinds of potential UV-complete models.Unlike the dimension-6 case,these limits apply regardless of the UV model setup and cannot be removed by possible cancellations among various UV contributions.This thus consists of a novel and universal test to confirm the Standard Model.We demonstrate with realistic examples how all the previously mentioned possibilities,including the test of positivity violation,can be achieved.Hence,we provide an important motivation for studying dimension-8 operators more comprehensively.
作者
Benjamin Fuks
刘一鸣
张岑
周双勇
Benjamin Fuks;Yiming Liu;Cen Zhang;Shuang-Yong Zhou(Sorbonne Université,CNRS,Laboratoire de Physique Théorique et HautesÉnergies,LPTHE,F-75005 Paris,France;Institut Universitaire de France,103 boulevard Saint-Michel,75005 Paris,France;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Center for High Energy Physics,Peking University,Beijing 100871,China;Interdisciplinary Center for Theoretical Study,University of Science and Technology of China,Hefei 230026,China;Peng Huanwu Center for Fundamental Theory,Hefei 230026,China)
基金
CZ is supported by IHEP(Y7515540UI)and National Natural Science Foundation of China(NSFC)(12035008)
SYZ acknow ledges suppont from the starting grants from University of Science and Technology of China(K20000089,GG2030040375)
is also supported by NSFC(12075233,11947301,12047502)
supprted by the Fundamental Rssearch Funds for the Central Universities(WK230000036)
This work has been supported by the FCPPL France China Particle Phys-ics Laboratory of the IN2P3/CNRS。