|MadSci Network: Physics|
I see a couple other people have asked this, but I am still wondering about elements with very large half lives (e.g. U238 - 4 Billion years, I think?) I understand that a large sample will have enough atoms decaying that they can be measured. Also we can determine the amount of the element present in a sample. But if decay is a completely random process (and random is the key to my problem), and the half life so long, how can we be sure of the results? Are uranium samples monitored for years? Even that wouldn't seem to yield a significant sample size, statistically speaking. What kind of confidence interval can be attained with such a small sample? Maybe I'm missing some fundamental understanding of the process. I just can't wrap my mind around determining a number so large (!) from a process of random decay measured over a "short" period of time. Any clarification you can offer is greatly appreciated!
Re: How is the half life of radioactive elements measured if it's very large?
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