Ghost-free scalar-fermion interactions

Rampei Kimura, Yuki Sakakihara, Masahide Yamaguchi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We discuss a covariant extension of interactions between scalar fields and fermions in a flat space-time. We show, in a covariant theory, how to evade fermionic ghosts appearing because of the extra degrees of freedom behind a fermionic nature even in the Lagrangian with first derivatives. We will give a concrete example of a quadratic theory with up to the first derivative of multiple scalar fields and a Weyl fermion. We examine not only the maximally degenerate condition, which makes the number of degrees of freedom correct, but also a supplementary condition guaranteeing that the time evolution takes place properly. We also show that proposed derivative interaction terms between scalar fields and a Weyl fermion cannot be removed by field redefinitions.

Original languageEnglish
Article number044043
JournalPhysical Review D
Volume98
Issue number4
DOIs
Publication statusPublished - 2018 Aug 15

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ghosts
fermions
scalars
degrees of freedom
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ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Ghost-free scalar-fermion interactions. / Kimura, Rampei; Sakakihara, Yuki; Yamaguchi, Masahide.

In: Physical Review D, Vol. 98, No. 4, 044043, 15.08.2018.

Research output: Contribution to journalArticle

Kimura, Rampei ; Sakakihara, Yuki ; Yamaguchi, Masahide. / Ghost-free scalar-fermion interactions. In: Physical Review D. 2018 ; Vol. 98, No. 4.
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