In cosmology,dark energy is some people suspect that refers to a kind of filled with space,has a strong negative pressure energy.According to the theory of relativity,the strong negative pressure in long distance is similar to a kind of anti-gravity.This conjecture is to explain the expansion of the universe to accelerate and lost in the universe material issues such as one of the most popular programs.The astronomer Edwin Hubble discovered other galaxies in the universe seems to be in the direction of the Milky Way of people's life more and more far distance.And they move further away,the faster running speed.Astrophysicist had previously pointed out,however,gravity makes the expansion rate is gradually slow down.Then,in 1998,two teams of researchers by observing the type Ia supernovae - rare phenomenon of exploding stars,can release a huge number of,the light of the persistent,overturns the astrophysicist theory is put forward.