Define radiometric dating method
Similarly, there is no way that it can be proved that these radioactive systems have been closed through all the supposed millions of years of decay of parent isotopes into daughter isotopes.Again, the main reason for this is because no scientist has been present to observe everywhere these radioactive systems and so report that they have been closed through all their history.The final assumption is, of course, that the radioactive decay rates have remained constant.However, once again, this assumption can in no way be proved, because there were no human observers present right throughout the earth’s history to be constantly measuring the radioactive decay rates and to have recorded them.Similarly, if the system has not remained closed (for example, if sand were somehow added or subtracted), then the calculation of the elapsed time, based on comparing the amounts of sand in the two glass bowls, will again lead to an incorrect conclusion.And finally, if the rate at which the sand grains fall from the top glass bowl to the bottom one varies (for example, moisture causes some clogging of the sand in the constriction between the two glass bowls), then again the hourglass ‘clock’ will be inaccurate.Now this ‘clock’ works because the initial conditions are known—that is, all the sand grains are in the top glass bowl and none are in the bottom one.If there is already some sand in the bottom glass bowl, then unless this amount is known the hourglass ‘clock’ cannot ‘tell’ the time.
Some types (technically known as ‘isotopes’) of ‘parent’ elements such as uranium, thorium, potassium and rubidium are said to be radioactive because the nuclei of the atoms are unstable, resulting in readjustments between the ‘particles’ (primarily neutrons and protons) in the nuclei with time.
Yet most people really don’t know much about these radioactive dating methods.
So slick and convincing are the presentations of results, particularly in glossy media and museum propaganda, that no one even bothers to question how these dating methods work, what assumptions are involved, and how reliable they are. The answers are not only instructive, but demolish the evolutionary geologist’s case for a 4.5-billion-year old earth.
At time t = 0, the hourglass is turned upside-down so that all the sand starts in the top bowl.
By time t = 1 hour, all the sand is supposed to have fallen into the bottom glass bowl.