How do we know the half life of C14 and how accurate is this answer?

Question

I know no one 5730 years ago decided to conduct this experiment so how is a half life determined. I'd love a confidence interval.

Shouldn't the very fact that I am questioning what I was told be enough to inform some people that I am not a die hard creationist?

Answer 1

Willard Libby estimated that about 14 disintegrations occured per minute per gram of C14 in the 50s. From this, extrapolations give an estimate of 5730 +/- 40 years.

There's more info on the wikipedia page

http://en.wikipedia.org/wiki/Radiocarbon_dating

http://en.wikipedia.org/wiki/Carbon-14

Answer 2

A study was done on dating a 4600 year old Bristlecone Pine by coring it to count tree rings and to carbon date its center (where no new growth has occurred and the C-14 clock was active). The results showed that C-14 dating tends to show slightly younger ages than found from counting tree rings. The error was on the order of 5%. This means that if the tree rings showed 4600 years the C-14 date showed 4550 years. In Science, an error of 5% is a good result.

Answer 3

2-sigma confidence interval is pretty standard on C-14 dating. That's about 95%.

As for your doubts about the abilities of nuclear physicists as compared to religious leaders when it comes to determining the properties of atoms, I suggest you read http://en.wikipedia.org/wiki/Half-life and then challenge the folks at Science & Mathematics > Physics with your discoveries of their flawed thinking. Afterwards, you might go on and challenge the Science & Mathematics > Astronomy & Space gurus with that whole speed of light fallacy they've been perpetuating.

One tends to wonder why you removed the question in which you linked to http://www.christiananswers.net/q-eden/edn-radioactive.html and I pointed out the references from the scientific journals they used were 40 years old and comperable to citing publications about computers from the 60's and 70's to show that they are of no practical use in every day life, and that at the very least it should make you more sure of the validity of radiometric dating since they were able to find so few examples of questionable work produced by anyone who didn't retire well before this century started. Surely you aren't protecting them, so maybe there is some hope if it's the fear of looking like a fool by association (with christiananswers.net) that made you remove the question.

Answer 4

C14 half life is 5,730 years with an error of 30 years.

Answer 5

The real problem (which no one mentioned in your previous post) is that the amounts of parent and daughter elements cannot be determined with a any degree of certainty...ESPECIALLY if one goes beyond the limited (few thousand) years of c-14 method.....

There is an assumption that the decay takes place in a 'sterile' (self -contained) environment....which is completely unreasonable.

All the physics of 'constancy' of decay rate is useless in such a case....since the correct original AMOUNT of parent element is indeterminable.

Here's a good quote from:
http://www.parentcompany.com/handy_dandy/hder12.htm:

“All of the parent and daughter atoms can move through the rocks. Heating and deformation of rocks can cause these atoms to migrate, and water percolating through the rocks can transport these substances and redeposit them. These processes correspond to changing the setting of the clock hands. Not infrequently such resetting of the radiometric clocks is assumed in order to explain disagreements between different measurements of rock ages. The assumed resettings are referred to as `metamorphic events’ or `second’ or `third events.’ ”

Answer 6

now and then is right....CI is 2 sigma....and chck this out for further info........http://en.wikipedia.org/wiki/Half-life