Sobering thought on “young Earth” theory: 4000 years (or 6000, or 10,000 how you squint at it) is 40 one-hundred year lifespans (or 60, or 100). That’s not long, especially when you’re pushing a half century yourself.
And yet all the physical evidence shows no evidence of mankind living for anything beyond 10k years [and even that is being generous] which is in complete agreement with the biblical account.
The link below shows just how much factual evidence evolutionary science is willfully ignoring [as they do with anything they can not explain].
101 Evidences for a Young Age of the Earth...And the Universe
http://creation.com/age-of-the-earth