Of course, there are many problems with such dating methods, such as parent or daughter substances entering or leaving the rock, as well as daughter product being present at the beginning.
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I didn't downvote, but I'm guessing whoever did has a couple of reasons in mind: (1) within the scope of physics, radiometric dating is perfectly valid, so it's kind of silly to ask whether it is - in other words, we don't care what the young-earth creationists think, and (2) your question doesn't really invite any exposition of the physical principles underlying radiometry.
Familiar to us as the black substance in charred wood, as diamonds, and the graphite in “lead” pencils, carbon comes in several forms, or isotopes.
One rare form has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or C ratio gets smaller.
Symbolically, the process of radioactive decay can be expressed by the following differential equation, where N is the quantity of decaying nuclei and k is a positive number called the exponential decay constant.
The meaning of this equation is that the rate of change of the number of nuclei over time is proportional only to the number of nuclei.
OK, well I meant it can be answered with "it's reliable." And your question definitely suggests that you are asking about the validity (a.k.a.
reliability) of the method, mostly because you start by saying "Young earth creationists dismiss radiometric dating as unreliable." If you take that out, you would be on your way to making a better question.
To me it has been a real eye opener to see all the processes that are taking place and their potential influence on radiometric dating.
Radiometric dating is largely done on rock that has formed from solidified lava.
Most scientists today believe that life has existed on the earth for billions of years.