The center of the earth is actually 2.5 years younger than its surface, and researchers say it all comes down to the effects of gravity as described by Einstein’s theory of general relativity.
According to Einstein’s theory, big objects like planets and stars warp space-time geometry, and this results in a gravitational pull capable of slowing down time. And, since our position in a gravitational field regulates the rate at which we experience time, the deeper we get in a large object’s gravity well, we would experience the greater the distortion of time.
In the paper published in the European Journal of Physics, lead researcher Ulrik Uggerhøj and his team R E Mikkelsen and J Faye, described the calculations involved in their effort to find time differential existing between the Earth’s core and surface.
In the 1960s, physicist Richard P. Feynman, in a series of lectures, claimed that the difference in age between the Earth’s center and surface was about a day or two. Since then, his claim has been cited in a number of scientific studies. But, a new study has found that he was right about time differential, but he miscalculated.
What Ulrik Uggerhøj predicted was that the effect of gravitational time dilation would be much greater on Earth than had initially been calculated. Because, since the Earth came to be, time at its core has been lagging behind time at the surface by 0.0000000003 of a second. This seems insignificant, but since the Earth is around 4.5 billion years old, the cumulative effect of this time dilation comes out to a difference of 1.5 years.
Also, considering the variations in density between the core and the surface, it was found that the difference in age is actually 2.5 years – ignoring geological processes.
The team also studied the effect of gravitational time dilation for the Sun and found that its core is around 40,000 years younger than its surface.