The team estimated from this that the Universe is about 12 billion years old much younger than previous estimates of 20 billion years. However, some of the team members and other researchers elsewhere also dated the oldest stars known those in the globular star clusters, at 13 to 14 billion years. The conflicting results created a paradox for researchers to unravel. The mystery might be solved using a second approach to dating the Universe. Astrophysicists have also run the expansion rate of the Universe backward in time.
Scientists pick an object and examine how far away it is from earth and how fast it is moving.
The size of the Universe is linked to the rate at which it expands. If the relationship between distance and speed is straight, then the expansion is happening at a constant rate. Dr. Peter Stetson, Herzberg Institute for Astrophysics research officer, compares the science to driving a straight line in a car. Of course, the amount of time it takes to travel a given distance changes when the relationship between time and space is curved. Einstein suggested the existence of a force, the Cosmological Constant that was strong enough to resist gravitational pull and would push the Universe apart.