Related papers: Instantons, the QCD Vacuum, and Hadronic Physics
We describe quenched spectroscopy in SU(2) gauge theory using smoothed gauge field configurations. We investigate the properties of quarks moving in instanton background field configurations, where the sizes and locations of the instantons…
The nonperturbative effects in the quark form factor are considered in the Wilson loop formalism. The properties of the Wilson loops with cusp singularities are studied taking into account the perturbative and nonperturbative contributions,…
I discuss the possible instanton-induced multiparticle production in hard processes in QCD Figures are available upon request
In quantum chromodynamics (QCD), the role which topologically non-trivial configurations play in splitting the singlet pseudo-Goldstone meson, the $\eta^\prime$, from the octet is familiar. In addition, such configurations contribute to…
Comparing the results of finite energy and Borel transformed sum rules for the difference of vector and axial vector current correlators we evaluate the instanton contributions to the $\tau$ hadronic width. In contrast to an explicit…
We briefly review the key aspect of the QCD instanton vacuum in relation to the quantum breaking of conformal symmetry and the trace anomaly. We use Ji$^\prime s$ invariant mass decomposition of the energy momentum tensor together with the…
When the theory of Quantum Chromodynamics was introduced, it was to explain the observed phenomena of quark confinement and scaling. It was then discovered that the emergence of instantons is an essential consequence of this theory. This…
We show that $QCD_2$ with adjoint fermions involves instantons due to nontrivial $\pi_1[SU(N)/Z_N]~=~Z_N$. At high temperatures, quasiclassical approximation works and the action and the form of effective (with account of quantum…
Assuming the gluon field is well approximated by instanton configurations we derive a partition function and calculate the specific correlators. Namely, the heavy quark propagator and heavy quark-aniquark correlator with the account of the…
We consider new instantons that appear as a result of accounting for quantum fluctuations. These fluctuations naturally regularize the O(4) singular solutions abandoned in Coleman's theory. In the previous works [3,4] we showed how new…
It is shown that the contribution of the instantons to the fragmentation of quarks leads to the appearance of a imaginary part in diagrams of quark-quark scattering at large transfer momentum. The imaginary part comes from the analytical…
The phonon-like excitations of (anti)-instanton liquid ($\bar II$) due to adiabatic variations of vacuum wave functions are studied in this paper. The kinetic energy term is found and proper effective Lagrangian for such excitations is…
First-principles calculations of multi-hadron dynamics are a crucial goal in lattice QCD. Significant progress has been achieved in developing, implementing, and applying theoretical tools that connect finite-volume quantities to their…
In this thesis we study two processes in which instantons may play an important role: the decays of charmonium states $\eta_c$, $\chi_c$ and glueball and the OZI violation in channels relevant to the proton spin decomposition puzzle. We…
QCD instantons are arguably the best motivated yet unobserved nonperturbative effects predicted by the Standard Model. A discovery and detailed study of instanton-generated processes at colliders would provide a new window into the…
In five spacetime dimensions, instantons are finite energy, solitonic particles. We describe the dynamics of these objects in the presence of a Chern-Simons interaction. For U(N) instantons, we show that the 5d Chern-Simons term induces a…
Parton physics, when formulated as light-front correlations, are difficult to study non-perturbatively, despite the promise of light-front quantization. Recently an alternative approach to partons have been proposed by re-visiting original…
Discovery of instantons in colliders will provide experimental evidence for the topological properties of the QCD vacuum. In this work, we propose jet correlation observables that can unambiguously discriminate between instanton-induced…
We consider the instanton contributions for the production of a gluon jet with large transverse momentum in QCD. We find that Mueller's corrections corresponding to the rescattering of hard quanta are likely to remove contributions of large…
Multi-instanton contributions to QCD sum rules for the pion are investigated within a framework which models the QCD vacuum as an instanton liquid. It is shown that in singular gauge the sum of planar diagrams in leading order of the…