Related papers: Quark-Hadron Duality
In this contribution to the proceedings, we analyze the transition from perturbative and non- perturbative QCD embedded in the coupling constant. In the study of quark-hadron duality, we suggest that the realization of the latter is related…
We discuss duality in ``two-photon''-like processes in the scalar $\varphi^3_E$ model and also in the process $\gamma^*\gamma\to\pi\pi$ in QCD. Duality implies the equivalence between two distinct nonperturbative mechanisms. These two…
A generalization of the operator product expansion for Euclidean correlators of gauge invariant QCD currents is presented. Each contribution to the modified expansion, which is based on a delocalized multipole expansion of a perturbatively…
We consider anyonic excitations classified into equivalence classes labeled by Hausdorff dimension, $h$ and introduce the concept of duality between such classes, defined by $\tilde{h}=3-h$. In this way, we confirm that the filling factors…
By applying chiral-perturbation-theory methods to the QCD sector of the Lorentz-violating Standard-Model Extension, we investigate Lorentz violation in the strong interactions. In particular, we consider the CPT-even pure-gluon operator of…
We discuss sum-rule determinations of $\alpha_s$ from non-strange hadronic $\tau$-decay data. We investigate, in particular, the reliability of the assumptions underlying the "truncated OPE strategy," which specifies a certain treatment of…
The three-flavor chiral expansion for octet baryons has well-known problems with convergence. We show that this three-flavor chiral expansion can be reorganized into a two-flavor expansion thereby eliminating large kaon and eta loop…
Jefferson Lab experiment E01-012 measured the He-3 spin-structure functions and virtual photon asymmetries in the resonance region in the momentum transfer range 1.0<Q**2<4.0(GeV/c)**2. Our data, when compared with existing deep inelastic…
We introduce the concepts of dual instruments and sub-observables. We show that although a dual instruments measures a unique observable, it determines many sub-observables. We define a unique minimal extension of a sub-observable to an…
We discuss the quantitative impact of duality violations on the determination of the strong coupling constant from hadronic tau decays, based on a preliminary analysis of OPAL data.
We discuss the production of two hadrons in e+e- annihilation within the framework of perturbative QCD. The cross section for this process is calculated to next-to-leading order accuracy with a selection of variables that allows the…
We compare the effects of different quark diagram topologies on the weak hadronic width of heavy-light mesons in the large N_c limit. We enumerate the various topologies and show that the only one dominant (or even comparable) in powers of…
We present a novel new approach to study quark-hadron duality using truncated moments of structure functions, and determine the degree to which individual resonance regions are dominated by leading twist.
This paper rests to a large extend on a paper I wrote some time ago on 'Duality in generalized Ising models and phase transitions without local order parameter'. It deals with Ising models with interactions containing products of more than…
We study the phenomenon of duality in hard exclusive reactions to which QCD factorization applies. Considering "two-photon"-like processes in the scalar $\phi^3_E$ model and also hadron-pair production from the collisions of a real…
We comment on the papers "Nucleon elastic form factors and local duality" [Phys. Rev. {\bf D62}, 073008 (2000)] and "Experimental verification of quark-hadron duality" [Phys. Rev. Lett. {\bf 85}, 1186 (2000)]. Our main comment is that the…
Weak radiative hyperon decays present us with a long-standing puzzle, namely the question of validity of a hadron-level theorem proved by Hara. We briefly discuss the conflict between expectations based on Hara's theorem and experiment as…
We exploit a new theory of duality transformations to construct dual representations of models incompatible with traditional duality transformations. Hence we obtain a solution to the long-standing problem of non-Abelian dualities that…
The Operator Product Expansion (OPE) of current correlators at short distances beyond perturbation theory in QCD, together with Cauchy's theorem in the complex energy plane, are the pillars of the method of QCD sum rules. This technique…
Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry $A_1$. Longitudinally polarised positrons were scattered off a longitudinally polarised…