ABSTRACT:
High energy limit of QCD is the area of major theoretical interest. One of its prediction is the so called perturbative BFKL
Pomeron which manifests itself as a rapid growth of the gluon density
with increasing centerofmass energy. Although the rise of this density is indeed observed in the deep inelastic experiments
at small values of Bjorken x, it is not compatible quantitatively with the prediction of the BFKL Pomeron.
This lead to the intensive investigation of the possible corrections
to the BFKL Pomeron such as higher order
and the high density corrections.
In this talk I will give an introduction to the high energy limit of QCD and discuss the idea of the parton saturation,
an effect that is expected to occur when the gluon density is very high.
I will describe the nonlinear evolution equation (BalitskyKovchegov equation) for the gluon density which takes into account high density corrections
and present its solution. The concept of the saturation scale and the geometrical scaling at small Bjorken x will be also introduced
as well as the interesting link between parton saturation in QCD and the statistical physics.
Finally, I discuss some phenomenological signatures of parton saturation and outline recent theoretical progress in
developing theory with socalled Pomeron loops, corrections which go beyond the BalitskyKovchegov equation.
