Radioactive dating

[dad1]

The basis for dating using ratios of isotopes is faith based. One example is that if we see an existing amount of parent and daughter material together, it is assumed that the present processes at work today are wholly responsible for all the material.

[DrNoGods]

[Replying to Sherlock Holmes in post #8]

I must correct you Dr, It is based on an assumed constant rate of radioactive decay (aka half-life).

I'll repeat my earlier question to dad1:

"Do you have any examples of any legitimate studies that show that this is not correct, or that there are deviations of any consequence?"

Observations suggest the decay rates are constant over time ... and until someone torpedoes that it is a valid assumption. Radiometric dating in general has been very valuable for all kinds of reasons ... the biggest objections seem to always come from people (like AIG and other religious groups) who don't like it because it contradicts their young Earth ideas.

[Sherlock Holmes]

[Replying to Sherlock Holmes in post #8]

I must correct you Dr, It is based on an assumed constant rate of radioactive decay (aka half-life).

I'll repeat my earlier question to dad1:

"Do you have any examples of any legitimate studies that show that this is not correct, or that there are deviations of any consequence?"

Observations suggest the decay rates are constant over time ... and until someone torpedoes that it is a valid assumption. Radiometric dating in general has been very valuable for all kinds of reasons ... the biggest objections seem to always come from people (like AIG and other religious groups) who don't like it because it contradicts their young Earth ideas.

Nobody said the assumption was not "valid", nobody said the dating process had no value, nobody said the half-life did not appear constant, only that it was an assumption.

A valid assumption and an invalid assumption are both nevertheless assumptions.

[Jose Fly]

I must correct you Dr, It is based on an assumed constant rate of radioactive decay (aka half-life).

I'm sure the Dr. will point this out (and I apologize for stepping in), but there are two responses to this old creationist talking point.

First, it is not merely "assumed". Again I have to wonder how you think geochronologists go about their work. Do you think they initially made an empty assumption that decay rates are constant and did nothing else? Not one of them ever thought, "Gee, maybe we should test that assumption"? The fact is, scientists have subjected radioactive decay to all sorts of extreme conditions and forces, and decay rates haven't budged. Extreme heat, pressure, magnetism, electricity, etc.....none cause rates to change. Also, given the issues surrounding radioactive waste from nuclear power, if creationists actually knew of a way to speed up decay rates they would change the world and make a fortune!

Second, radioactive decay occurs in one of three ways: alpha decay, beta decay, and electron capture. All three are completely independent of each other, so when scientists utilize different isotopes that decay by different means and still get overlapping results, that's pretty powerful confirmation of accuracy. After all, what would cause different isotopes that decay by completely different means to give the same results?

Let's be honest here....the only reason this even comes up in places like this is because some creationists don't like the fact that the science has consistently given answers that conflict with their religious beliefs. So rather than accept reality and adjust their beliefs accordingly, they just go into reflexive denial mode and deny the results no matter what.

[DrNoGods]

[Replying to Sherlock Holmes in post #10]

The half-life is assumed to be constant, in physics the time at which any atom will decay seems to be completely unpredictable, random.

Right ... Shrodinger's Cat depends on it.

The statistically computed half-life might be constant but we do not know, nobody was around to measure the half-life tens of thousands of years ago, for all we know it changes slowly according to some as-yet undiscovered law, we don't know so we assume. It's reasonable to assume but whether it be reasonable or unreasonable isn't the question, in either case it is an assumption not an objective verifiable fact.

So why not continue with the assumption of constant decay rates until someone can show that this isn't valid? We have no reason to believe that the atoms that existed in the past are any different whatsoever from the atoms of today (same number of protons, neutrons and electronics for any given isotope). Radioactive decay is determined primarily by the atomic structure and if this has not changed over time why would you expect the radioactive decay rates to change over time to any significant extent?

Take the Hubble "constant" that too is now no longer regarded as constant, it was assumed (reasonably so too) for years but that assumption now looks wrong, in science we must always be aware of what we've assumed because we may have adjust such assumptions as we learn more.

Of course ... we'd still be trying to date certain mollusk shells with 14-C dating if we didn't learn about the reservoir effect. Any nontrivial measurement using instrumentation has to consider all of the relevant parameters that can produce bad results ... with the instrumentation, how it is used, and the sample or observation.

[DrNoGods]

[Replying to Jose Fly in post #13]

Let's be honest here....the only reason this even comes up in places like this is because some creationists don't like the fact that the science has consistently given answers that conflict with their religious beliefs. So rather than accept reality and adjust their beliefs accordingly, they just go into reflexive denial mode and deny the results no matter what.

Yes ... I've never heard a creationist complain about a science issue that did not contradict a religious belief, or challenge such beliefs. Their criticism is always directed at things like radiometric dating, the geologic column and the fossil record, etc. that show an old Earth and support evolution over creation. Never hear them complaining about the many science topics that do not tread on these subjects.

I suppose they have to operate this way to defend their beliefs, although I've never understand why they don't just say they adopt their beliefs based on faith and leave it at that instead of trying to make them compatible with modern science. Seems a pointless exercise in most cases.

[Sherlock Holmes]

[Replying to Sherlock Holmes in post #10]

The half-life is assumed to be constant, in physics the time at which any atom will decay seems to be completely unpredictable, random.

Right ... Shrodinger's Cat depends on it.

The statistically computed half-life might be constant but we do not know, nobody was around to measure the half-life tens of thousands of years ago, for all we know it changes slowly according to some as-yet undiscovered law, we don't know so we assume. It's reasonable to assume but whether it be reasonable or unreasonable isn't the question, in either case it is an assumption not an objective verifiable fact.

So why not continue with the assumption of constant decay rates until someone can show that this isn't valid?

You can continue, I never questioned the utility of the assumption.

We have no reason to believe that the atoms that existed in the past are any different whatsoever from the atoms of today (same number of protons, neutrons and electronics for any given isotope). Radioactive decay is determined primarily by the atomic structure and if this has not changed over time why would you expect the radioactive decay rates to change over time to any significant extent?

I have no idea if the rate has changed or does change, all I said is that it is an assumption to claim it doesn't.

Take the Hubble "constant" that too is now no longer regarded as constant, it was assumed (reasonably so too) for years but that assumption now looks wrong, in science we must always be aware of what we've assumed because we may have adjust such assumptions as we learn more.

Of course ... we'd still be trying to date certain mollusk shells with 14-C dating if we didn't learn about the reservoir effect. Any nontrivial measurement using instrumentation has to consider all of the relevant parameters that can produce bad results ... with the instrumentation, how it is used, and the sample or observation.

Hubble's constant was for years assumed (and justifiably so) to be a universal constant, a law. In this case though it now appears that the assumption was wrong, anything that's assumed can turn out to be wrong. A scientist should always be clear about what they're assuming.

[dad1]

This is strictly speaking - true, I agree, it is based on assumptions. Take carbon dating for example, this assumes that rate of C14 production in the atmosphere (as a result of cosmic ray activity) was the same in the past as it is today and also assumes that the half-life of C14 was the same in the past as it is today. But we have no data from thousands of years ago about either of these parameters - hence we assume.

In other words, from a standpoint of ignorance in the extreme, some assume God was wrong in Genesis. Then some turn around and say the bible is not authoritative!

But this basic calculation assumes that the amount of carbon-14 in the environment has been constant in time and space — which it hasn’t. In recent decades, the burning of fossil fuel and tests of nuclear bombs have radically altered the amount of carbon-14 in the air, and there are non-anthropogenic wobbles going much further back. During planetary magnetic-field reversals, for example, more solar radiation enters the atmosphere, producing more carbon-14. The oceans also suck up carbon — a little more so in the Southern Hemisphere, where there is more ocean — and circulate it for centuries, further complicating things.

There it is, "assumes" the OP is correct, it is based on assumptions, faith, trust etc.

It sure is. Basically another religion.

[Jose Fly]

Yes ... I've never heard a creationist complain about a science issue that did not contradict a religious belief, or challenge such beliefs. Their criticism is always directed at things like radiometric dating, the geologic column and the fossil record, etc. that show an old Earth and support evolution over creation. Never hear them complaining about the many science topics that do not tread on these subjects.

And what's really odd is how many of them absolutely refuse to acknowledge the role their religious beliefs play in how they view the conclusions of science. It's weird.

I suppose they have to operate this way to defend their beliefs, although I've never understand why they don't just say they adopt their beliefs based on faith and leave it at that instead of trying to make them compatible with modern science. Seems a pointless exercise in most cases.

I think it's because in today's society science has become our primary means of establishing reality, thus the creationists realize that if their beliefs are in conflict with science, a lot of people will just go with the science. So they do whatever they can to make it seem as if their beliefs really are supported by science, even to the point of outright lying (see: quote mining).

The good thing is, it isn't working.

[dad1]

[Replying to dad1 in post #1]

The basis for dating using ratios of isotopes is faith based.

No it isn't. It is based on a constant rate of radioactive decay which is what is observed.

I allow the dates are good FOR AS LONG AS IT HAS BEEN OBSERVED!! Beyond that time, YES, it certainly is.

Isochron dating helps to improve the results (eg. uranium 238 decays to lead 206, uranium 235 decays to lead 207, but lead 204 does not arise from the radioactive decay of uranium so can be used to confirm the parent levels of lead independent of the uranium products).

False.

How would we know that the source of the material had to be modern day processes and laws? Again you believe real hard, nothing more.

The "faith" you refer to I assume means the constant decay rate over time.

No! ANY decay over time! How do we know the present forces that cause decay existed as we know them? Maybe there was some different balance and even forces? Who knows? You just use the laws and physics today to explain all we see. That is belief. 100%

Do you have any examples of any legitimate studies that show that this is not correct, or that there are deviations of any consequence? This is an observation, not faith (belief without evidence).

No such thing as any legitimate study that deals with forces and laws in the far far past. That means ALL your studies are 100% belief and totally illegitimate!

[Jose Fly]

Told ya.