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Reverted edits by BobtheBuilder2 (talk) to last revision by Valuables
Another assumption is that the rate of decay is constant.
Another assumption is that the rate of decay is constant.
There is no reason to expect that the rate of decay of a radioactive material is largely constant,<ref>At least one example of a change in the rate has been observed in laboratory experiments. See Walker, 2000.</ref> and it was almost certainly not constant near the creation or beginning of the universe.
There is no reason to expect that the rate of decay of a radioactive material is largely constant,<ref>At least one example of a change in the rate has been observed in laboratory experiments. See Walker, 2000.</ref> and it was almost certainly not constant near the creation or beginning of the universe.
The process of decay is as follows. Atoms consist of a heavy central core called the [[nucleus]] surrounded by clouds of lightweight particles (electrons), found in [[electron shell]]s. The energy locked in the nucleus is enormous, but cannot be released easily. The phenomenon we know as heat is simply the vibration of atoms, so in principle a high enough temperature could cause the components of the core to break out. However, the temperature required to do this is in in the millions of degrees, so this cannot be achieved by any natural process that we know about.
The process of decay is as follows. Atoms consist of a heavy central core called the [[nucleus]] surrounded by clouds of lightweight particles (electrons), called [[electron shell]]s. The energy locked in the nucleus is enormous, but cannot be released easily. The phenomenon we know as heat is simply the jiggling around of atoms and their components, so in principle a high enough temperature could cause the components of the core to break out. However, the temperature required to do this is in in the millions of degrees, so this cannot be achieved by any natural process that we know about. The second way that a nucleus could be disrupted is by particles striking it. However, the nucleus has a strong positive charge and the electron shells have a strong negative charge. Any incoming negative charge would be deflected by the electron shell and any positive charge that penetrated the electron shells would be deflected by the positive charge of the nucleus itself.
=== Outside influences ===
=== Outside influences ===
Otherwise, calibration consists of comparing results with ages determined by other radiometric dating methods.
Otherwise, calibration consists of comparing results with ages determined by other radiometric dating methods.
However, tests of radiometric dating methods have often shown that they do ''not'' agree with known ages of rocks that have been seen to form from volcanic eruptions in recent and historic times, and there are also examples of radiometric dating methods not agreeing with each other.
[[Young earth creationists]] therefore claim that radiometric dating methods are not reliable and can therefore not be used to disprove Biblical chronology.
== Acceptance and reliability ==
== Acceptance and reliability ==
Another scientist later used other methods to derive a date of 62,000 years.
Another scientist later used other methods to derive a date of 62,000 years.
The original discoverer, unconvinced by this result, used a different method again, and again came up with a date of 40,000 years.
The original discoverer, unconvinced by this result, used a different method again, and again came up with a date of 40,000 years.
The fallibility of dating methods is also illustrated by the fact that dating laboratories are known to improve the likelihood of getting a "correct" date by asking for the expected date of the item. For example, the Sample Record Sheet for the University of Waikato Radiocarbon Dating Laboratory asks for the estimated age, the basis for the estimate, and the maximum and minimum acceptable ages.<ref>[http://www.radiocarbondating.com/submission%20form%202003.pdf University of Waikato Radiocarbon Dating Laboratory Sample Record Sheet]</ref>
==Some major methods of radiometric dating==
==Some major methods of radiometric dating==