God's Clocks in Nature
Rod Nave, Ph.D., Dept of Physics and Astronomy, Georgia State University
This session will be a brief overview of time - the way it is measured and the way it is affected by relativity. It will also deal with the kind of clocks we find in nature. What does it take to be considered one of God's clocks? The primary emphasis will be on methods for time measurement that appear to be tamperproof by man. On the large scale in the universe, there are light sources that appear to have a standard brightness, like Cepheid variable stars and Type-1A supernovas. Their measured brightness is then a measure of distance, and with the known speed of light they become a measure of time. On the earth the radioactive decay of a nucleus is quite impervious to anything man can throw at it outside a direct particle impact in an accelerator. The methods of time measurement will be discussed and an assessment of the reliability of these clocks will made.