Related papers: Instanton Effects in Matrix Models and String Effe…
The effect of D-instantons on closed string scattering amplitudes may be encoded into an effective action obtained by integrating out the (transient) open string fields. In order that this respects the gauge invariance of the theory, the…
Motivated by possible implications on the problem of moduli stabilization and other phenomenological aspects, we study D-brane instanton effects in flux compactifications. We focus on a local model and compute non-perturbative interactions…
We consider systems of magnetized D9 branes on orbifolds supporting N=1 gauge theories. In such realizations, the matter multiplets arise from "twisted" strings connecting different stacks of branes. The introduction of Euclidean 5-branes…
Certain quantum mechanical potentials give rise to a vanishing perturbation series for at least one energy level (which as we here assume is the ground state), but the true ground-state energy is positive. We show here that in a typical…
We propose a method to evaluate hadronic matrix elements of QCD gluon operators in the instanton vacuum. We construct the ground state of the interacting instanton ensemble for non-zero $\vartheta$--angle using a variational principle. A…
We compute instanton corrections to the partition function of sine-Liouville (SL) theory, which provides a worldsheet description of two-dimensional string theory in a non-trivial tachyon background. We derive these corrections using a…
Effective theories provide a powerful tool for testing the Standard Model and for searching for the effects of new physics in a model-independent manner. In general one assumes that the effects of new physics characterized by a high-energy…
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…
Instantaneous interactions in Standard Model are derived by the resolution of the Gauss constraints in inertial reference frames defined as irreducible representations of the Poincare group. The relativistic covariant and gauge-invariant…
We study the effect of D-instantons on closed string scattering amplitudes in the two-dimensional type 0B string theory from the worldsheet perspective. We find that the contribution from a pair of D-instanton and anti-D-instanton to the…
We compute the effect of small-size instantons on the coefficient function of the chiral condensate in the operator product expansion of current-current correlators. Furthermore, we also compute the instanton corrections associated with…
Non-perturbative effects of instanton-like solutions are studied within the framework of supergravity theories with field-dependent gauge functions. Fermionic zero modes are constructed and some typical correlation functions are evaluated.…
Pionless effective field theory with dibaryon fields is reexamined for observables involving the deuteron. The electromagnetic form factors of the deuteron and the total cross sections of radiative neutron capture on the proton, $np \to…
Instanton effects on the Euclidean correlation function of two Wilson loops at an angle $\theta$, relevant to soft high-energy dipole-dipole scattering, are calculated in the Instanton Liquid Model and compared with the existing lattice…
Instanton contributions in 2d string theory are known to include subtle numerical factors $\zeta_n$ closely related to a contour prescription in multi-instanton string amplitudes. Both ingredients appear to be ambiguous due to a degeneracy…
We investigate the instanton effects of non-BPS D0-brane in type I string theory. We argue the general properties of these instanton effects and consider these on $R^9\times S^1$ as a simple example using the effective action of D0-brane.
Nontrivial topological structures of non-Abelian gauge fields were discovered in the 1970's. Instanton solutions, describing vacuum tunneling through topological barriers, have fermionic zero modes which are at the origin of $^\prime$t…
The nonperturbative effects in the high-energy processes involving strongly interacting particles are studied within the instanton liquid model of the QCD vacuum (ILM) by using the Wilson integral framework. The detailed analysis of…
Instanton analysis is applied to models B--H of critical dynamics. It is shown that the static instanton of the massless $\phi^{4}$ model determines the large-order asymptotes of the perturbation expansion of these near-equilibrium dynamic…
We consider stringy instanton contributions to the prepotential of low-energy N=2 theories engineered by D-brane set ups at orbifold and orientifold singularities. We show that such contributions can always be reproduced in a purely field…