[split] Radiometric Dating

[Surgenator]

By my name you probably know my position, but I have a little bit of a beef with radio metric dating because of its presuppositions. Basically there are three:
1) you have to assume the absence of the daughter isotope at the start of process.

Nope. We've seen these decays in the lab. So seeing the decay products as well the reactants is not an assumption but deduction.

2) you have to assume constant decay rates. We have only been able to observe their rates for the past 100-150 years. Before that we can reasonably guess the affects of the earth's magnetic field and other factors would have on decay, but that is all they will ever be: an educated guess.

Nucleur reactors depend on these decay rates to be constant. You need to know the state of your reactor if you want to run it.

The earth's magnetic field have no effect on decay rates. CERN has a magnetic field of 4 Tesla (8000 greater than the earth's) and sees the same decays.

You should show evidence of decay rates changing, because all the evidence is saying it doesn't.

3) no parent or daughter isotopes were lost or added during the process.
I'm going to leave it at that and see where the replies take it. Hope to here from you guys soon.

Again, we have seen these decays in the lab. We know the products and the likelihood the products would escape. A good example of this is the uranium-238 decay chain. Along the chain, Radon is produced and can escape from Rock through osmosis. If you only find rocks that have the latter half (post Radon) products, you have to compare products ratios instead of totals. But if you look at the early chain half (before Radon), your can go back to totals.