>>But what if the assumptions are wrong? For example, what if radioactive material was added to the top bowl or if the decay rate has changed?
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>When discussing radiometrics they argue that decay rates cannot be assumed to be constant because no can verify that change has not happened.
Except that the second part is another valid way to change the results. Let’s say we have maggots and flies and they behave the same way as radioactive decay, that at every so often half of the maggots will change into flies. Now if we have a set number of maggots, say 1000 in some sealed environment and come back some time later we can estimate how much time has elapsed by measuring the number of flies/maggots there are and applying what we know about exponential growth/decay curves. (There is one exception: after a while there is NO reliability in determining a maximum age, but rather a minimum age emerges; in this case I think that happens around 10 or 11 halflives.)
Now, let’s say you have an environment that is still sealed but another scientist comes in and, not realizing you’re in the middle of something, adds or removes flies or maggots? Then, when you try to apply your knowledge about exponential growth/decay you will get erroneous conclusions.
And every time you repeat this experiment some other scientist comes in and does the same thing, so that you keep getting the same erroneous results over and over again?