We highlight the progress, current status, and open challenges of QCD-driven physics, in
theory and in experiment. We discuss how the strong interaction is intimately connected to a …

We review the theoretical developments and conceptual advances that stemmed from the
generalization of QCD to the limit of a large number of color charges, originally proposed by't …

1. Introduction 2. The Gross-Neveu Model 3. QCD 3.1 N-Counting Rules for Diagrams 3.1. 1
U (1) Ghosts 3.2 The't Hooft Model 3.3$ N $-Counting Rules for Correlation Functions 3.4 …

The conceptual interpretation of valence-and sea-quark separation, which is a key aspect of
the parton model and of an intuitive picture of hadron structure, becomes obscured by …

The masses of the negative parity 70-plet baryons are analyzed in large N c QCD to order
1/N c and to first order in SU (3) symmetry breaking. The existing experimental data are well …

The generalization of the color gauge group SU (3) to SU (N c), with N c taking arbitrarily
large values, as had been proposed and developed by't Hooft, has allowed for a decisive …

▪ Abstract A spin-flavor symmetry emerges for baryons in the large-Nc limit. Large-Nc
baryons form irreducible representations of the spin-flavor algebra, and their static …

We consider in detail the mass operator analysis for the nonstrange l= 1 excited baryons in
large N c QCD. We present a straightforward procedure for constructing the large N c baryon …

The mass spectrum of the positive parity [56, 2+] baryons is studied in the 1/Nc expansion up
to and including O (1/N c) effects with SU (3) symmetry breaking implemented to first order. A …

The masses of the negative parity SU (6) 70-plet baryons are analyzed in the 1/N c
expansion to order 1/N c and to first order in SU (3) breaking. At this level of precision there …