Dark Energy and the Accelerating Universe: Challenges and Opportunities

Abstract

The authors of this article start from the observation of unexpected luminosity of type la supernovae in 1998 Supernova Cosmological Project to the classification of dark energy in the ΛCDM model, and finally to the modern theory of dark energy model, including Dynamical Dark Energy, Interacting Dark Energy theory and Holographic Dark Energy theory. The concept of cosmological constant is illustrated, leading to the introducing of the two main problems encountered when investigating dark energy, Fine-tuning and coincidence problems. As possible solutions to these cosmological problems, Holographic Dark Energy and Interacting Dark Energy are introduced as a supplement to the theory of Dynamical Dark Energy, all of which are trending theory with the potential to provide a consistent explanation and model for dark energy and simultaneously accelerating expansion of the universe. Space observation projects and existing theories are combined to illustrate possible future developments in dark energy theories which also link back to the Standard Model of physics, such as Quantum Gravity theory.