Hugh,
- I haven't really stepped back. I'm just slow. My buddies here can vouch for me on that.
- I am surprised that you give the carbon dating so much credibility. I'm currently reviewing the relevant articles on shroud.com, and am still impressed with the apparent room for error...
- I'll eventually get back with what I can dig up.
I've more or less quit the site, but broke my rule for this post.
Radiocarbon dating isn't perfect. No dating method is. However, the thing Jabba is trying to get the peanut gallery to not notice is that scientists
know what can affect the measurements. We know that marine organisms show a clear bias, and even have a name for it. We know that various processes can introduce dead carbon into the system, and have a name for that, too. We know that more C14 can be made, via radiation interacting with N14, and we have all KINDS of ways to detect that (seeing as how it's foundational to the whole concept).
There are two posibilities for a mistake with C14 dating of the shroud. The nearly infinitely more likely source is dead carbon from the burning of fossil fuels--meaning that carbon from coal fires or oil lamps burning petroleum products could become integrated in the cloth. This is a widely known issue and there are specific protocols for addressing it. Second--and the ONLY way that C14 dating can be biased in such a way as to support Jabba's conclusions--is if the shroud were irradiated with exactly the right amount of exactly the right type of radiation, converting the N14 into C14 and artificially lowering the age. I suppose the shroud may have reached its closing temperature for C14, but without offgassing there's really nowhere for the C14 to go, and even if it did the offgassing would alter the ratio of C14 to C12/C13, which means we could back-calculate it. (That's something Jabba will never tell folks: we don't just use one dating method, even for the same sample--we use a number of them combined, such as lookign at parent/daugher ratios AND ratios of parent isotopes to stable ones. Look at U/U dating and concordance for more information.)
We know that neither was a singificant factor, because we have at this point firmly established the provenance of the shroud. It did not exist before the Middle Ages. This is the second thing Jabba wants to hide from the peanut gallery: the C14 dating has been confirmed by other dating methods. There is NO way that the same process can bias both of these methods, so they act as an independent test of one another.
Finally, the sheer hypocracy of accepting a test of dubious value conducted under uncontrolled conditions, while demanding rigorous yet routine tests to be held to unobtainable standards in order to accept their results, clearly shows that Jabba is basing his acceptance of tests on whether they agree with his a priori conclusion or not. The issue was never whether the C14 tests were valid or not--they got an answer that Jabba disagrees with, so he is hunting for an excuse to dismiss them. He is looking for a "Gotcha!" situation, where he can formulate an excuse to dismiss the evidence while pretending to be operating within the accepted manner of science.
hugh farey said:
In science, it is simply not enough to explain why you are right, you must also explain why those who disagree with you are wrong.
You left out quite a bit here. For example, if the reason you're wrong is general knowledge (remember that general knowledge in a group of experts is different from general knowledge of the population as a whole), there is no need to discuss your claim. And if your claim has already been refuted, referencing the refutation is an acceptable method for "explain[ing] why those who disagree with you are wrong".