https://biblio.ugent.be/publication/685594/file/1130605.pdf

Review of Particle Physics

It is shown that the global charges of a gauge theory may yield a nontrivial central extension of the asymptotic symmetry algebra already at the classical level. This is done by studying three dimensional gravity with a negative cosmological constant. The asymptotic symmetry group in that case is eitherR×SO(2) or the pseudo-conformal group in two dimensions, depending on the boundary conditions adopted at spatial infinity. In the latter situation, a nontrivial central charge appears in the algebra of the canonical generators, which turns out to be just the Virasoro central charge.

/pdf/central-charges-in-the-canonical-realization-of-asymptotic-3j5vmhw3pr.pdf

Central Charges in the Canonical Realization of Asymptotic Symmetries: An Example from Three-Dimensional Gravity

We review the present status of QCD corrections to weak decays beyond the leading-logarithmic approximation, including particle-antiparticle mixing and rare and $\mathrm{CP}$-violating decays. After presenting the basic formalism for these calculations we discuss in detail the effective Hamiltonians of all decays for which the next-to-leading-order corrections are known. Subsequently, we present the phenomenological implications of these calculations. The values of various parameters are updated, in particular the mass of the newly discovered top quark. One of the central issues in this review are the theoretical uncertainties related to renormalization-scale ambiguities, which are substantially reduced by including next-to-leading-order corrections. The impact of this theoretical improvement on the determination of the Cabibbo-Kobayashi-Maskawa matrix is then illustrated. [S0034-6861(96)00304-2]

Weak decays beyond leading logarithms

String theory axions appear to be promising candidates for explaining cosmological constant via quintessence. In this paper, we study conditions on the string compactifications under which axion quintessence can happen. For sufficiently large number of axions, cosmological constant can be accounted for as the potential energy of axions that have not yet relaxed to their minima. In compactifications that incorporate unified models of particle physics, the height of the axion potential can naturally fall close to the observed value of cosmological constant.

https://iopscience.iop.org/article/10.1088/1126-6708/2006/06/051/pdf

Axions In String Theory

/pdf/review-of-particle-physics-1996-1997-jeg703df6k.pdf

Review of Particle Physics, 1996-1997

Chiral quarks and the non-relativistic quark model

Two Z's or not two Z's?

We investigate the current-mass ratios of the light quarks by fitting the squared meson masses to second order in chiral-symmetry breaking, determining corrections to Weinberg's first-order values: m/sub u//m/sub d/ = 0.56, m/sub s//m/sub d/ = 20.1. We find that to this order, m/sub s//m/sub d/ is a known function of m/sub u//m/sub d/. The values of the quark-mass ratios can be constrained by limiting the size of second-order corrections to the squares of meson masses. We find that for specific values of presently unmeasured phenomenological parameters one can have a massless u quark. In that case 30% of the squares of meson masses arise from operators second order in chiral-symmetry breaking.

Aneesh Manohar

Papers

Chiral quarks and the non-relativistic quark model

Two Z's or not two Z's?

Current-Mass Ratios of the Light Quarks

Equivalence of the Chiral Soliton and Quark Models in Large N

The evaporation of Q-balls