Magnetic Vortices from a Nonlinear Sigma Model with Local Symmetry

It is shown that the low-energy physics of an extended Abbott-Farhi model with two scalar doublets is described by a nonlinear sigma model based on SP (4)/ SU (2)× SU (2), which possesses an SU(2) gauge invariance as a hidden symmetry. This raises the interesting possibility of identifying the weak bosons observed at the collider experiments with the composite gauge bosons associated to such a hidden local symmetry.

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Hidden local symmetry and beyond

International Journal of Modern Physics E ◽

10.1142/s0218301317400328 ◽

2017 ◽

Vol 26 (01n02) ◽

pp. 1740032 ◽

Cited By ~ 9

Author(s):

Koichi Yamawaki

Keyword(s):

Dark Matter ◽

Vector Meson ◽

Sigma Model ◽

Local Symmetry ◽

Kinetic Term ◽

Nonlinear Sigma Model ◽

Nonlinear Realization ◽

Additional Symmetry ◽

The Standard Model ◽

Work Done

Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry [Formula: see text] based on the manifold [Formula: see text], and thus is universal to any physics based on the nonlinear realization. Here, I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on [Formula: see text] with additional symmetry, the nonlinearly-realized scale symmetry. Then, the SM does have a dynamical gauge boson of the SU[Formula: see text] HLS, “SM [Formula: see text] meson”, in addition to the Higgs as a pseudo-dilaton as well as the NG bosons to be absorbed in to the [Formula: see text] and [Formula: see text]. Based on the recent work done with Matsuzaki and Ohki, I discuss a novel possibility that the SM [Formula: see text] meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call “dark SM skyrmion (DSMS)”.

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Old wine in a new bottle: Technidilaton as the 125 GeV Higgs

International Journal of Modern Physics A ◽

10.1142/s0217751x17470261 ◽

2017 ◽

Vol 32 (36) ◽

pp. 1747026

Author(s):

Koichi Yamawaki

Keyword(s):

Sigma Model ◽

Local Symmetry ◽

Effective Theory ◽

Nonlinear Sigma Model ◽

Scale Invariant ◽

Gauge Bosons ◽

Strongly Coupled ◽

Technicolor Model ◽

Vector Bosons ◽

The One

The first Nagoya SCGT workshop back in 1988 (SCGT 88) was motivated by the walking technicolor and technidilaton. Now at SCGT15 I returned to the “old wine” in “a new bottle”, the recently discovered 125 Higgs boson as the technidilaton. We show that the Standard Model (SM) Higgs Lagrangian is identical to the nonlinear realization of both the scale and chiral symmetries (“scale-invariant nonlinear sigma model”), and is further gauge equivalent to the “scale-invariant Hidden Local Symmetry (HLS) model” having possible new vector bosons as the HLS gauge bosons with scale-invariant mass: SM Higgs is nothing but a (pseudo) dilaton. The effective theory of the walking technicolor has precisely the same type of the scale-invariant nonlinear sigma model, thus further having the scale-invariant HLS gauge bosons (technirho’s, etc.). The technidilaton mass [Formula: see text] comes from the trace anomaly, which yields [Formula: see text] via PCDC, in the underlying walking [Formula: see text] gauge theory with [Formula: see text] massless flavors, where [Formula: see text] is the the decay constant and [Formula: see text]. This implies [Formula: see text] for [Formula: see text] in the one-family walking technicolor model [Formula: see text], in good agreement with the current LHC Higgs data. In the anti-Veneziano limit, [Formula: see text], with [Formula: see text]fixed and [Formula: see text]fixed [Formula: see text], we have a result: [Formula: see text]. Then the technidilaton is a naturally light composite Higgs out of the strongly coupled conformal dynamics, with its couplings even weaker than the SM Higgs. Related holographic and lattice results are also discussed. In particular, such a light flavor-singlet scalar does exists in the lattice simulations in the walking regime.

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The nonlinear sigma model and spin ladders

Journal of Physics A General Physics ◽

10.1088/0305-4470/29/12/032 ◽

1996 ◽

Vol 29 (12) ◽

pp. 3299-3310 ◽

Cited By ~ 76

Author(s):

Germán Sierra

Keyword(s):

Sigma Model ◽

Nonlinear Sigma Model

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Nonlinear sigma model with particle-hole asymmetry for the disordered two-dimensional electron gas

Physical Review B ◽

10.1103/physrevb.103.125422 ◽

2021 ◽

Vol 103 (12) ◽

Author(s):

Georg Schwiete

Keyword(s):

Sigma Model ◽

Electron Gas ◽

Nonlinear Sigma Model ◽

Two Dimensional ◽

Dimensional Electron ◽

Two Dimensional Electron Gas ◽

Dimensional Electron Gas

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Massive gravity from double copy

Journal of High Energy Physics ◽

10.1007/jhep12(2020)030 ◽

2020 ◽

Vol 2020 (12) ◽

Cited By ~ 1

Author(s):

Arshia Momeni ◽

Justinas Rumbutis ◽

Andrew J. Tolley

Keyword(s):

Sigma Model ◽

Massive Gravity ◽

Effective Field ◽

Effective Theory ◽

Nonlinear Sigma Model ◽

Limit Theory ◽

Four Dimensions ◽

Yang Mills ◽

Massive Spin ◽

Double Copy

Abstract We consider the double copy of massive Yang-Mills theory in four dimensions, whose decoupling limit is a nonlinear sigma model. The latter may be regarded as the leading terms in the low energy effective theory of a heavy Higgs model, in which the Higgs has been integrated out. The obtained double copy effective field theory contains a massive spin-2, massive spin-1 and a massive spin-0 field, and we construct explicitly its interacting Lagrangian up to fourth order in fields. We find that up to this order, the spin-2 self interactions match those of the dRGT massive gravity theory, and that all the interactions are consistent with a Λ3 = (m2MPl)1/3 cutoff. We construct explicitly the Λ3 decoupling limit of this theory and show that it is equivalent to a bi-Galileon extension of the standard Λ3 massive gravity decoupling limit theory. Although it is known that the double copy of a nonlinear sigma model is a special Galileon, the decoupling limit of massive Yang-Mills theory is a more general Galileon theory. This demonstrates that the decoupling limit and double copy procedures do not commute and we clarify why this is the case in terms of the scaling of their kinematic factors.

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