reply to post by poet1b
You are saying that the net change means that this doesn't make the whole dating process questionable, when the Standford article clearly
states that it does, because the overall variability is to large to not question whether or not this can be considered a constant.
If you review the peer-reviewed paper that the Stanford article is based on, the change in counting rate for Ra226 is 0.003. This translates to a
fluctuation of +/- 0.308 years over a half-life of 1601 years, or a maximum fluctuation of 0.02%. Is a maximum fluctuation of three months over a
period of over a millennium and a half large enough of a deviation to overturn all of the radioisotope dating we’ve done to date? In my opinion, no.
Especially since, as shows in the paper, the variations are cyclic.
The articles you cited about supernova radioisotope decay are about identifying different species of radioactive materials in deep space.
Radioisotope decay of carbon 14 for dating is a different process. This requires looking at specific materials, and measuring the decay. This is not
what they are doing when looking at species of radioactive materials in deep space. They have to have the samples of known carbon 14 to establish the
decay rates, they don't have those samples from deep space. They can only measure the combination of frequencies of gamma rays to identify categories
of these emissions.
I’m sorry, I don’t think I expressed my point clearly enough. Yes, C14 is mentioned early on in the Stanford article. However, none of the
research performed by Jenkins et al was in regards to C14 - they were working with Si32 and Ra226. They do suggest that the same phenomenon should
have an effect on all radioisotopes, but that it will take more research to verify. My specific point is that if decay rates were “drifting” here
on Earth, as you suggest, we’d see variation between the decay rate of a radioisotope here on Earth and the same radioisotope under different
conditions i.e. in space. We don’t.
Calculations are based on previously measured values.
No, calculations made from first principles are done independently of empirical measurements. That’s why they’re called calculations from first
Acceleration is the speed of the rate of change, not the total change. If you are in a car 60 mph, and accelerate at 5 mph per minute for five
minutes, and then drop to 0 mph per minute acceleration, you will then be moving at 85 mph, having change the rate of travel from 60 to 85, or 25 mph.
It is the change in rate, not the speed of the change of rate that is important here. Maybe I am being nitpicky.
Yes, and in order to exhibit a net change in a rate, there must be a net acceleration or deceleration of that rate. Or, in other words, in order for
you to get from 60 to 85 mph, you still had to have accelerated more than you decelerated. In the case of decay rates, you have a population of
particles (N) that is changing over a period of time (t). This changes is referred to as the activity (A) and is defined as –[dN/dt], or as a
reduction in the species over time in the case of decay. What we’re talking about here is a change in A with time, or dA/dt. If you look at the
original peer-reviewed paper that the Stanford article is based on, it shows that the variations as measured by the research teams are cyclic and that
the averages are still constant when taken over a sufficiently long period of time i.e. no drift.
I hope I'm not giving the impression that I think they're not seeing what they're claiming or that it's not an important finding. It absolutely is and
I can't wait to see the results of the experiments that will be conducted in order to test the various hypotheses for why this is occurring. I just
don't think it's going to have any effect on radiometric dating methods. If anything, I think this will ultimately provide for more accurate
measurement of half-lives and help resolve the discrepancies previously found in half-life measurements that had no explanation other than
edit on 25/4/2011 by iterationzero because: fixed italics tag
edit on 25/4/2011 by iterationzero because:
apparently i'm really bad at tags
edit on 25/4/2011 by iterationzero because: ...really really bad at tags.