Radiometric dating is possible if
The Christian Creationists have criticised it on the grounds that it is innacurate.
But these innacuracies are the result of variation in the level of Carbon 14 in the atmosphere, and when this is worked out (through calibration with tree rings of the bristlecone pine, the oldest living organism) precise dates can be had.
With the discovery of radiometric dating, it became possible for the first time to attempt precise figures.
Radiometric dating works on the principle that certain atoms and isotopes are unstable.
By matching the proportion of original unstable isotope to stable decay product, and knowing the half-life of that element, one can thus deduce the age of the rock , as shown in the follwoing diagram.
The radioactive isotope Carbon 14 has a half-life of 5,730 years.
Ihis has made it useful for measuring prehistory and events occurrring within the past 35 to 50 thousand years.
Different world-views have different time-scales as regards the history of the Earth and the universe.
Buddhist, Jain and Hindu cosmologies describe the universe as a never-ending series of cycles each lasting millions or billions of years.