We show that the chiral symmetry breaking occurs in the vacuum of the massless Nambu-Jona-Lasinio (NJL) and Thirring models without a Goldstone boson. The basic reason of non-existence of the massless boson is due to the fact that the new vacuum after the symmetry breaking acquires nonzero fermion mass which inevitably leads to massive bosons. The new vacuum has a finite condensate of 〈ψ̄ψ〉 with...

The LHC experiment will soon probe how W and Z bosons acquire their masses. So far we have only indirect hints about the actual mechanism of electroweak symmetry breaking. The standard model (SM) introduces a weakly coupled fundamental scalar field—the Higgs field— whose condensation breaks the electroweak symmetry. This simple picture is consistent with precision electroweak measurements, if t...

We derive the nonanalytic chiral behavior of the flavor asymmetry d - u. Such behavior is a unique characteristic of Goldstone boson loops in chiral theories, including QCD, and establishes the unambiguous role played by the Goldstone boson cloud in the sea of the proton. Generalizing the results to the SU(3) sector, we show that strange chiral loops require that the s - s distribution be nonzero.

The conceptual issues of low-energy baryon physics are discussed. In particular , a comparison between the naive one gluon exchange model for the interaction between constituent quarks in hadrons and the Goldstone boson exchange picture is made. The " defects " of the Goldstone boson exchange model for baryons, indicated by Isgur [1] are examined in detail. All of the purported " defects " are ...

We consider QCD at a nonzero chemical potential for strangeness. At a critical value of the chemical potential equal to the kaon mass, kaon condensation occurs through a continuous phase transition. We show that in the limit of exact isospin symmetry a Goldstone boson with the dispersion relation E ∼ p appears in the kaon condensed phase. At the same time, the number of the Goldstone bosons is ...

Various topics in and around Goldstone Boson Production and Decay in CHPT are discussed, in particular I describe some of the progress in p Chiral Perturbation Theory Calculations, the progress in calculating hadronic contributions to the muon anomalous magnetic moment, here comparing the two latest results of the light-by-light in some detail. I also present some progress in various η and K de...

I discuss the exciting prospects for Higgs and technicolor Goldstone boson physics at a muon collider.