I've pondered a hypothetical problem Take as time perspective "A" as being relative time dilation of Earth Time dilation "B" being half of "A" slower due to relativistic effects. assuming both "A" and "B" were both formed at the same time say 5 billion years ago. If you were to measure the age of the universe with "A" getting the result of 13.7 billion years. would "B" see the age as 11.2 billion years ? or would "B" still measure the age of the universe at 13.7 Billion years?