How do you prove the earth is old in the easiest way possible? If you decide to go with atom decomposition, you have to also be able to show the decomposition rate and the exponential law which describes it. I don't want to calculate its exact age, but prove it is at least as old as 10000 years. A few million years would be nice.
I don't want the historical way of proving it, I want the easiest, just as the Foucault pendulum is the easiest way to prove the earth rotates on itself, even though it was shown centuries earlier by heliocentricism, which was derived from planet trajectories. I don't think the various atom dating techniques are the best way to do it.
I don't mind people editing my question but please keep its original meaning.