Proponents of an Old Earth rely on the assumption that the [[Radiometric dating|rate of radioactive decay]] remains constant over thousands of years. In fact, a large number of physical processes, such as neutron capture and fluctuations in solar radiation, can affect the rate of radioactive decay of elements in the Earth's crust and render radioactive dating measurements unreliable with errors up to 5%, depending upon the specific methods used.<ref>http://www.sciencedirect.com/science/article/pii/S0899536205000138#bib6</ref> Even so, such an error will not cause a calculation of the age of the Earth based on radiometric dating to be off by up to five [[order of magnitude|orders of magnitude]]. | Proponents of an Old Earth rely on the assumption that the [[Radiometric dating|rate of radioactive decay]] remains constant over thousands of years. In fact, a large number of physical processes, such as neutron capture and fluctuations in solar radiation, can affect the rate of radioactive decay of elements in the Earth's crust and render radioactive dating measurements unreliable with errors up to 5%, depending upon the specific methods used.<ref>http://www.sciencedirect.com/science/article/pii/S0899536205000138#bib6</ref> Even so, such an error will not cause a calculation of the age of the Earth based on radiometric dating to be off by up to five [[order of magnitude|orders of magnitude]]. |