Interacting Agegraphic Dark Energy

A new dark energy model, named as “agegraphic dark energy”, has been proposed by one of us (R. G. Cai) in arXiv:0707.4049, based on the Károlyházy uncertainty relation, which arises from the quantum mechanics together with general relativity. In this note, we extend the original agegraphic dark energy model by including the interaction between the agegraphic dark energy and the pressureless (dark) matter. In the interacting agegraphic dark energy model, there are many interesting features different from the original agegraphic dark energy model and holographic dark energy model, for examples, the model parameter n > 1 is no longer necessary to drive the accelerated expansion of our universe; the equation-of-state parameter (EoS) of agegraphic dark energy can cross the phantom divide, whereas the big rip can be avoided; the universe undergoes decelerated expansion at early time and then starts accelerated expansion later; there are scaling solutions which can help to alleviate the coincidence problem. The similarity and difference between the agegraphic dark energy and holographic dark energy are also discussed. PACS numbers: 95.36.+x, 98.80.Qc, 98.80.-k ∗ email address: [email protected] † email address: [email protected]