How scientist found age of universe as 13.8 billion years and age of Milky Way as 13.51 Billion years? Is there any proof?

  • 1
    $\begingroup$ Physics is not math - asking for a mathematical proof is not asking for physics. $\endgroup$
    – Jon Custer
    Sep 28, 2018 at 16:38
  • $\begingroup$ any proof from physics point of view? $\endgroup$ Sep 28, 2018 at 16:40
  • $\begingroup$ Related: physics.stackexchange.com/q/11136/2451 and links therein. $\endgroup$
    – Qmechanic
    Sep 28, 2018 at 17:42

1 Answer 1


It's impossible to mathematically "prove" those things in the way that mathematicians prove axioms. Instead, physicists compare the predictions of a model of the universe with experimental observations made on it in order to verify the correctness of that model; those observations having certain statistical limits on their stated accuracy. They also use that data to refine their models so as to include more physics in them and thereby increase their predictive power and accuracy.

Finally, physicists make comparisons between different models to determine whether or not their own model is consistent with those others, within the accuracy limits mentioned above. This process is used to rule in or rule out the validity of the model in question.

None of these processes rely on mathematical proof as such.

  • $\begingroup$ thank you sir for answering but I need to know how they reached to that number (13.8 billion year). $\endgroup$ Sep 28, 2018 at 17:08
  • $\begingroup$ Hello Ardash, sorry I misinterpreted your question- the number for the age of the universe was "back-calculated" from data collected by the COBE microwave survey satellite a few years ago, suggest you googlesearch on COBE & AGE OF UNIVERSE to find out the algorithm they used. $\endgroup$ Sep 28, 2018 at 20:46

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