Related papers: High Energy Theorems at Large-N
Correlators of the octet baryons in the hot pion gas are studied in the framework of the QCD sum rule. The condensates appearing in the OPE side of the correlators become T-dependent through the interaction with thermal pions. We present an…
The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of quantum chromodynamics (QCD) sum rules. We evaluate the vacuum-to-vacuum transition matrix…
Corrections of order $T^4$ to vector and axial current correlators in QCD at a finite temperature $T<T_c$ are obtained using dispersion relations for the amplitudes of deep inelastic scattering on pions. Their relation with the operator…
QCD sum rules are used to calculate the $q^2$ dependence of the $\pi NN$ coupling $g_{\pi NN} (q^2)$ in the spacelike region $0.5 \ {\mbox{GeV}}^2 \lesssim q^2 \lesssim 1.5\ {\mbox{GeV}}^2$. We study the Borel sum rule for the three point…
We calculate the coupling constants between the light vector mesons and heavy mesons within the framework of the light-cone QCD sum rule in the leading order of heavy quark effective theory. The sum rules are very stable with the variations…
The noncommutative (NC) massive quantum electrodynamics in $2+1$ dimensions is considered. We show explicitly that the one-loop effective action arising from the integrating out the fermionic fields leads to the ordinary NC Chern-Simons and…
Non-Abelian gauge theories "live" in a space-time with non-trivial topology that can be characterized by an odd-dimensional Chern-Simons form. In QCD, Chern-Simons form is induced by the chiral anomaly and the presence of topological…
(Chern--Simons) vector models exhibit an infinite-dimensional symmetry, the slightly-broken higher-spin symmetry with the unbroken higher-spin symmetry being the first approximation. In this note, we compute the $n$-point correlation…
We calculate the nucleonic and pionic dispersion relations at finite temperature T and non-vanishing chemical potentials $(\mu_f)$ in the context of an effective chiral theory that describes the strong and electromagnetic interactions for…
In multiquark correlator analyses with 1/Nc classifications, it is possible to separate the scattering background and to justify the factorization of condensates, which allows us to achieve an isolated peak saturation in the QCD sum rules…
The in-medium behavior of the nucleon spectral density including self-energies is revisited within the framework of QCD sum rules. Special emphasis is given to the density dependence of four-quark condensates. A complete catalog of…
We analyse the structure of current-current correlators in coordinate space in large $N_c$ limit when the corresponding spectral density takes the form of an infinite sum over hadron poles. The latter are computed in the QCD string model…
We consider diagonal and non-diagonal QCD sum rules for the ground state heavy baryons to leading order in $1/m_Q$ and at next-to-leading order in $\alpha_S$. In the non-diagonal case we evaluate the eight different two-loop diagrams which…
Recently E.Verlinde and H.Verlinde have suggested an effective two-dimensional theory describing the high-energy scattering in QCD. In this report we attempt to clarify some issues of this suggestion. We consider {\it anisotropic…
A visible improvement of the QCD sum-rule framework, achieved only recently by a slightly more sophisticated consideration of the hadron excitations and continuum, is applied to the extraction of the decay constants of heavy-light…
Electromagnetic decays of the scalar mesons are shown to be constrained by chiral symmetry as a consequence of the fact that, in the chiral limit, the two and three-point functions $<SS-PP>$ and $<VVS>$ satisfy super-convergent dispersion…
We study the effective action describing high-energy scattering processes in the multi-Regge limit of QCD, which should provide the starting point for a new attempt to overcome the limitations of the leading logarithmic and the eikonal…
We consider the scattering of two color dipoles (e.g., heavy quarkonium states) at low energy - a QCD analog of Van der Waals interaction. Even though the couplings of the dipoles to the gluon field can be described in perturbation theory,…
How fast does the quark condensate in QCD-like theories vary as a function of $N_f$ is inferred from real QCD using chiral perturbation theory at order one-loop. A sum rule is derived for the single relevant chiral coupling-constant, $L_6$.…
Equal time, point to point correlation functions for spatially separated meson currents are calculated with respect to a variational construct for the ground state of QCD. With exact calculations, vector, axial vector and scalar channels…