An effective theory of accelerated expansion

Understand

We work out an effective theory of accelerated expansion to describe general phenomena of inflation and acceleration (dark energy) in the Universe.

• Our aim is to determine from theoretical grounds, in a physically-motivated and model independent way, which and how many (free) parameters are needed to broadly capture the physics of a theory describing cosmic acceleration.
• Our goal is to make as much as possible transparent the physical interpretation of the parameters describing the expansion.
• We show that, at leading order, there are five independent parameters, of which one can be constrained via general relativity tests.