Related papers: A Goldstone Boson Primer
These notes review the effective lagrangian treatment of Goldstone and pseudo-Goldstone bosons, taking examples from high-energy/nuclear and condensed-matter physics. The contents are: 1. Goldstone Bosons 2. Pions: A Relativistic…
The paper concerns the effective field theory methods used to study the low energy structure of systems with a spontaneously broken symmetry. I first explain how the method works in the context of quantum chromodynamics and then discuss a…
We set up the effective field theories which describe the SO(5)-invariant picture of the high-Tc cuprates in various regimes. We use these to get quantitative conclusions concerning the size of SO(5)-breaking effects. We consider two…
This paper gives a simple introduction to the SO(5) theory of high T_c superconductivity. Current status and relation to experiments are summarized.
We formulate the Josephson effect in a field theoretic language which affords a straightforward generalization to the non-abelian case. We give some examples and apply the formalism to the case of SO(5) superconductivity.
An overview is presented of the talks in the working group on Goldstone Bosons. Topics touched on are CP-violation in the Kaon system, rare Kaon decays, $\pi\pi$-scattering, $\phi$-meson decays, scalar mesons, form-factors and…
Pseudo-Goldstone bosons in 4D strongly coupled theories have a dual description in terms of 5D gauge theories in warped backgrounds. We introduce systematic methods of computing the pseudo-Goldstone potential for an arbitrary warp factor in…
We consider nonrelativistic superfluids where the global U(1)-symmetry is spontaneously broken. At sufficiently long wavelengths, the relevant degree of freedom is the massless Goldstone mode and we construct an effective low energy theory…
The hard thermal loop effective action for Goldstone bosons is deduced by symmetry arguments from the corresponding result for gauge bosons. Pseudoscalar mesons in Chromodynamics and magnons in an antiferromagnet are discussed as special…
I review aspects of the theory of the weak interaction in a set of lectures originally presented at the 2016 CERN-JINR European School of Particle Physics. The topics discussed are: (1) the experimental basis of the V-A structure of the…
The low-energy physics of antiferromagnets is governed by their Goldstone bosons -- the magnons -- and it is described by a low-energy effective field theory. In analogy to baryon chiral perturbation theory, we construct the effective field…
These lecture notes review the theoretical background to the Higgs boson, provide an introduction to its phenomenology, and describe the experimental tests that lead us to think that "beyond any reasonable doubt, it is a Higgs boson".…
It has been proposed that the effective Hamiltonian describing high T_c superconductivity in cuprate materials has an approximate SO(5) symmetry relating the superconducting (SC) and antiferromagnetic (AF) phases of these systems. We show…
By electron or hole doping quantum antiferromagnets may turn into high-temperature superconductors. The low-energy dynamics of antiferromagnets are governed by their Nambu-Goldstone bosons -- the magnons -- and are described by an effective…
We study the role of fermionic resonances in realistic composite Higgs models. We consider the low energy effective description of a model in which the Higgs arises as the pseudo-Goldstone boson of an SO(5)/SO(4) global symmetry breaking…
In this talk, an SU(Nf)xSU(Nf)Yang-Mills model with a compact extra-dimension is used to describe the spin-1 mesons and pions of massless QCD in the large-Nc. The right 4D symmetry and symmetry-breaking pattern is produced by imposing…
New theories of electroweak symmetry breaking have recently been constructed that stabilize the weak scale and do not rely upon supersymmetry. In these theories the Higgs boson is a weakly coupled pseudo-Goldstone boson. In this note we…
We study the Higgs condensation $H={\bar t}t$ mechanism in the Top-mode Standard Model at the next-to-leading order in 1/Nc. The calculation includes the effects of the Goldstone fields, but not the effects of the transverse components of…
In this lecture we show that the study of hadronic resonances is severely hampered by the lack of accurate data and, moreover, that for similar reason the study of Weak substructure does not make sufficient progress. We furthermore report…
A short overview of recent progress in describing kaon and pion decays within Chiral Perturbation Theory is presented. Particular attention is devoted to the issues of final-state interactions and isospin breaking in $K \to 2 \pi$, as well…