Geometry of the scalar sector

Journal Article · Wed Aug 17 00:00:00 EDT 2016 · Journal of High Energy Physics (Online)

DOI:https://doi.org/10.1007/JHEP08(2016)101· OSTI ID:1434582

Alonso, Rodrigo ^[1]; Jenkins, Elizabeth E. ^[2]; Manohar, Aneesh V. ^[2]

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1. University of California, San Diego, La Jolla, CA (United States). Department of Physics
2. University of California, San Diego, La Jolla, CA (United States). Department of Physics; CERN TH Division, Geneva (Switzerland)

The S-matrix of a quantum field theory is unchanged by field redefinitions, and so it only depends on geometric quantities such as the curvature of field space. Whether the Higgs multiplet transforms linearly or non-linearly under electroweak symmetry is a subtle question since one can make a coordinate change to convert a field that transforms linearly into one that transforms non-linearly. Renormalizability of the Standard Model (SM) does not depend on the choice of scalar fields or whether the scalar fields transform linearly or non-linearly under the gauge group, but only on the geometric requirement that the scalar field manifold M is flat. Standard Model Effective Field Theory (SMEFT) and Higgs Effective Field Theory (HEFT) have curved M, since they parametrize deviations from the flat SM case. We show that the HEFT Lagrangian can be written in SMEFT form if and only ifMhas a SU(2)_L U(1)_Y invariant fixed point. Experimental observables in HEFT depend on local geometric invariants of M such as sectional curvatures, which are of order 1/Λ² , where Λ is the EFT scale. We give explicit expressions for these quantities in terms of the structure constants for a general G → H symmetry breaking pattern. The one-loop radiative correction in HEFT is determined using a covariant expansion which preserves manifest invariance of M under coordinate redefinitions. The formula for the radiative correction is simple when written in terms of the curvature of M and the gauge curvature field strengths. We also extend the CCWZ formalism to non-compact groups, and generalize the HEFT curvature computation to the case of multiple singlet scalar fields.

• Research Organization: University of California, San Diego, La Jolla, CA (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0009919
• OSTI ID: 1434582
• Journal Information: Journal of High Energy Physics (Online), Vol. 2016, Issue 8; ISSN 1029-8479
• Publisher: Springer Berlin
• Country of Publication: United States
• Language: English

Related Subjects

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