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Does the Gravitational Pull on an Object Affect its Age?

-- Edgar | January 26, 2021

Question:

When Determining Stars, Planets and Galaxies Age, Aren’t we suppose to consider the Gravitation force of it? Since the Size will vary for each, the Space-time will also be curved differently and will have a direct effect on how we should count its age.

Thank you.

-- Edgar

Answer:

I believe what you are referring to is one of the predictions of Einstein’s General Theory of Relativity, which predicts that the rate of change of time experienced by an object in a the gravitational field of massive object like a planet or star will be slower, or dilated, when the massive object’s gravitational pull is taken into account.  In fact, gravity’s affects on the rate of change of time was measured in 2010 by scientists using very accurate clocks.  For massive objects like stars, planets, and galaxies gravity’s affect on time is very small.  For example, the Earth’s gravitational field causes time to slow by only a few billionths of a second over a time period of about 100 years when an object is moved one centimeter closer to the Earth.  This time dilation due to the Earth’s gravity results in the Earth’s core being about 2.5 years younger than its surface, which is only a tiny fraction of the total 4.5 billion year age of the Earth.

-- Jeff Mangum