Related papers: Is chiral symmetry manifested in nuclear structure…
A survey is given of the evolution from Yukawa's early work, via the understanding of the pion as a Nambu-Goldstone boson of spontaneously broken chiral symmetry in QCD, to modern developments in the theory of the nucleus based on the…
We take an approach to the $\Lambda$ nonmesonic weak decay in nuclei based on the exchange of mesons under the guidelines of chiral Lagrangians. The one pion and one kaon exchange are considered, together with the exchange of two pions,…
Three instances are discussed in which results produced by chiral perturbation theory can be reliably pushed to high space-like values of transferred momenta: 1. nuclear interactions, 2. nucleon sigma-term and 3. space-like structure of the…
Spontaneous breaking of chiral symmetry is discussed in the light-cone framework. The essential ingredient is an infinite number of constituents near zero light-cone momentum. These high (light-cone) energy degrees of freedom freeze out and…
We prove a strong form of spontaneous breaking of rotational symmetry for a simple model of two-dimensional crystals with random defects in thermal equilibrium at low temperature. The defects consist of isolated missing atoms.
Exact symmetry and symmetry-breaking phenomena play a key role in providing a better understanding of the physics of many-particle systems, from quarks and atomic nuclei, to molecules and galaxies. In atomic nuclei, exact and dominant…
We study nuclear physics in the chiral limit ($m_u$, $m_d=0$) in which the pion mass vanishes. We find that the deuteron mass is changed little, but that P--wave nucleon--nucleon scattering volumes are infinite. This motivates an…
We study the nuclear modification of the scalar QCD susceptibility, calculated as the derivative of the quark condensate with respect to the quark mass. We show that it has two origins. One is the low lying nuclear excitations. At normal…
I report on recent work done in collaboration with M. Knecht on patterns of spontaneous chiral symmetry breaking in the large-Nc limit of QCD-like theories, and with S. Peris and M. Perrottet concerning the question of matching long and…
The implications of chiral symmetry breaking and SU(3) symmetry breaking have been studied in the chiral constituent quark model ($\chi$CQM). The role of hidden strangeness component has been investigated for the scalar matrix elements of…
The chiral symmetry breaking in the 4-dimensional QED with the chirally invariant four-fermion interaction is discussed by using a novel path integral expression in terms of the field-strength tensor. In the local potential approximation,…
The symmetry energy of nuclear matter is a fundamental ingredient in the investigation of exotic nuclei, heavy-ion collisions and astrophysical phenomena. New data from heavy-ion collisions can be used to extract the free symmetry energy…
A geometric mechanism that may, in analogy to similar notions in physics, be considered as "symmetry breaking" in geometry is described, and several instances of this mechanism in differential geometry are discussed: it is shown how…
It is shown that by an appropriate canonical transformation Kepler dynamics can be put in the form which allows to exhibit the structure of the symmetry transformations related to the superintegrability. They appear to fit nicely into…
The constraints imposed by chiral symmetry on hadron correlation functions in nuclear medium are discussed. It is shown that these constraints imply some structure of the in-medium hadron correlators, lead to the cancellation of the order…
A brief review of the isospin symmetry breaking in hadrons and nuclei is given with emphasis on the $u-d$ quark mass difference. The off-shell $\rho^0-\omega$ mixing is studied as a typical example of the symmetry breaking, and its…
Chiral symmetry and its spontaneous breaking play an important role both in the light hadron and heavy hadron systems. The chiral perturbation theory ($\chi$PT) is the low energy effective field theory of the QCD. In this work, we shall…
The catalysis of chiral symmetry breaking in the massless weakly coupled QED in a magnetic field is studied. It is shown that the effect is due to the dimensional reduction $D\to D-2$ in the dynamics of fermion pairing in a magnetic field.…
The projected shell model with configuration mixing for nuclear chirality is developed and applied to the observed rotational bands in the chiral nucleus $^{130}$Cs. For the chiral bands, the energy spectra and electromagnetic transition…
There are numerous examples of approximately degenerate states of opposite parity in molecular physics. Theory indicates that these doubles can occur in molecules that are reflection-asymmetric. Such parity doubles occur in nuclear physics…