Holographic quantum gravity models have indeed been proposed as possible explanations for cosmological acceleration. These models draw inspiration from the holographic principle, which suggests that the information content of a three-dimensional region can be encoded on a two-dimensional surface, such as a black hole's event horizon.

In the context of cosmology, holographic quantum gravity models often involve a modification of the Einstein field equations, the fundamental equations governing the behavior of gravity in general relativity. These modified theories, such as AdS/CFT (Anti-de Sitter/Conformal Field Theory) correspondence, or other holographic approaches, introduce additional geometric terms or scalar fields that give rise to accelerated expansion.

One specific example is the dS/CFT correspondence, which relates a de Sitter spacetime, a solution to Einstein's equations representing an accelerating universe, to a conformal field theory (CFT) living on the boundary of the spacetime. In this framework, the accelerated expansion is associated with the properties and dynamics of the CFT.

However, it's important to note that while holographic quantum gravity models provide potential explanations for cosmological acceleration, they are still subjects of active research and debate within the field of theoretical physics. There are different holographic approaches, and each has its own assumptions, challenges, and implications. Ultimately, the validity of these models and their ability to explain cosmological acceleration require further theoretical development, observational tests, and a deeper understanding of quantum gravity.