Stars cannot run forever, they explode eventually, and other stars can form from the debris: https://www.quora.com/What-is-a-third-generation-star?utm_medium=or

Stars cannot run forever, they explode eventually, and other stars can form from the debris: https://www.quora.com/What-is-a-third-generation-star?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa https://www.quora.com/What-is-a-third-generation-star?utm_me... For the Universe having certain age - I don't understand it, b/c whatever is 13 billion years for one, might be 1 sec for another, due to relativistic time dilation. I think of this number as a kind of metaphor :)