Loop Quantum Cosmology: A cosmological theory with a view

Guillermo A. Mena Marugán

Loop Quantum Gravity is a background independent, nonperturbative approach for the quantization of General Relativity. Its application to models of interest in cosmology and astrophysics, known as Loop Quantum Cosmology, has led to new and exciting views of the gravitational phenomena that took place in the Early Universe, or that occur in spacetime regions where Einstein's theory predicts the appearance of singularities. We provide a brief introduction to the bases of Loop Quantum Cosmology and summarize the most important results obtained in homogeneous scenarios, which include a mechanism to avoid the cosmological Big-Bang singularity and replace it with a Big Bounce or, as another example, the existence of processes which favour initial conditions for inflation. We also discuss the extension of the frame of Loop Quantum Cosmology to inhomogeneous settings and overview the advances that have been reached recently in this direction.