Related papers: On the instanton-induced portion of the nucleon st…
We calculate the instanton contribution to the proton strangeness in the MIT bag enriched by the presence of a dilute instanton liquid. The evaluation is based on expressing the nucleon matrix elements of bilinear strange quark operators in…
On top of its valence quarks, the full nucleon ground state may contain appreciable admixture of s-\bar{s} pairs already at small momentum transfers. This paper discusses strangeness in the mean-field type of nucleon models, and exemplifies…
The contribution of instanton-induced effective inter-quark interactions to the baryon mass splittings was considered in the bag model. It is found that results are different from those obtained in the constituent quark model where the…
We describe the simplest example of an instanton bag in Euclidean space. It consists of a monopole wall and a Kaluza-Klein monopole wall, lifted to one higher dimension, trapping the instanton charge in the middle. This object has finite…
Most of model considerations of the hidden nucleon strangeness, as well as some preliminary experimental evidence, led to the expectations of relatively sizeable strange vector form factors of the proton. For example, it seemed that the…
Recent developments in the density dependence of the MIT bag radius and parameters in nuclear matter are discussed. Starting from the MIT bag lagrangian density, the calculations are specialized for symmetric homogeneous isotropic nuclear…
Strangelets with non-zero entropy are studied within the MIT bag model. Explicit account is taken of the constraints that strangelets must be color neutral and have a fixed total momentum. In general, masses increase with increasing entropy…
The quark-meson coupling model for nuclear matter, which describes nuclear matter as non-overlapping MIT bags bound by the self-consistent exchange of scalar and vector mesons, is modified by introducing medium modification of the bag…
The modified quark-meson coupling model, which features a density dependent bag constant and bag radius in nuclear matter, is checked against the EMC effect within the framework of dynamical rescaling. Our emphasis is on the change in the…
We study the electro-magnetic form factors of the nucleon, from small to large momentum transfer, in the context of the Instanton Liquid Model (ILM). As a first step, we analyze the role of single-instanton effects, and show that they…
We construct improved QCD sum rules for the nucleon magnetic moments by implementing direct-instanton contributions to the operator product expansion of the nucleon correlator in a magnetic background field. The instanton contributions are…
The influence of nonperturbative fields on instantons in quantum chromodynamics is studied. Effective action for instanton is derived in bilocal approximation and it is demonstrated that stochastic background gluon fields are responsible…
An alternative to introducing and subsequently renormalizing classical parameters in the expression for the vacuum energy of the MIT bag for quarks is proposed in the massless case by appealing to the QCD trace anomaly and scale separation…
We review our current understanding of instanton effects in the large N_c limit of QCD. We argue that the instanton liquid can have a smooth large N_c limit which is in agreement with scaling relations derived from Feynman diagrams. We also…
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…
We examine the contribution of small instantons to the axion mass in various UV completions of QCD. We show that the reason behind the potential dominance of such contributions is the non-trivial embedding of QCD into the UV theory. The…
The binary interaction of large size instantons in a SU(2) Yang-Mills theory is obtained from the one-loop effective action for the field strength. The instanton interaction is calculated as a function of the instanton separation and in…
Recently it was demonstrated that magnon condensation in the trap exhibits the phenomenon of self-localization. When the number of magnons in the textural trap increases, they drastically modify the profile of the gap and highly increase…
A self-consistent description of the MIT bag parameters as functions of the nuclear matter density is presented. The subnuclear degrees of freedom are treated in the Quark-Meson Coupling Model, considering the equilibrium conditions for the…
We study instanton effects in QCD at very high baryon density. In this regime instantons are suppressed by a large power of $(\Lambda_{QCD}/\mu)$, where $\Lambda_{QCD}$ is the QCD scale parameter and $\mu$ is the baryon chemical potential.…