Atheist:If radioactive materiel has a half life, that allows you to date its age does this imply?

Question

If radioactive materiel has a half life, that allows you to date its age does this imply?
Its Decay started at a specific moment in time?
So I was wondering how did things start being radioactive?
Is there a moment or process identifiable with the start of this decay?

Or are radioactive substances in a state of decay from the moment they come into existence?

Conan, I am addressing this to the Atheist that didn't answer when I asked in Physics 3 days ago.

Answer 1

Radioactive materials start decaying from the instance they were formed. What you talk about is carbon dating.
Radioactive carbon 14 is constantly formed in the athmosphere. Plants and through feeding on plants everything organic constantly takes up some amount of carbon-14. They don't after they are dead. As they don't take up any new carbon (neither radioactive nor non-radioactive isomers) and the existing radioactive isomers decay with a known rate, the amount of radioactive carbon in the organism will decrease over time. This can be used to approximate how much time has passed since that organism died.
Look up for more detail on the wikipedia website.

Could you please explain why you address this question to atheists? It really belongs into the science section. Do you think if anybody knows anything about science they automatically turn into an atheist? Or what is the logic here?

Answer 2

Radioactive substances decay from the moment they come into existence.
If the question is suggesting that by extrapolating backwards, there will be a doubling for every half life, then asking how much should have been the quantity of radio active material at the birth of this earth, I do not know.
It should be easily calculable.
It is very likely that in the beginning the earth was a lot more radio active than it is to day.

Answer 3

The thing about a "half life" is that it describes the statistics of a population where "death" (in this case, radioactive decay to a different atom) has an equal chance of occurring at any instant. The smaller the chance of a decay per second, the longer the halflife.

Elements that undergo radioactive decay are made in stars, generally in supernovae. From that instant, each of the radioactive nuclei has an equal chance of decaying in each second. Yes, they have a chance to decay from the moment they come into existence. But if they haven't decayed yet, they are "as good as new". There is no clock in each individual nucleus that "knows" how long it has been since it was formed, it's just that there's an equal chance of decay in each second.

Roughly speaking, the way radioactive dating works is this:
1) some process like photosynthesis or formation of minerals, causes a bunch of radioactive atoms to accumulate in one place.
2) as time goes on, some of those nuclei decay into other nuclei.
3) at some later time, a scientist measures the amount of the remaining, non-decayed nuclei, and also the amount of the surrounding decay products. A correction may need to be made for decay product nuclei that also accumulate in step 1.

This ratio of non-decayed nuclei to decay products allows the time since step (1) to be estimated.

Answer 4

Radioactive elements are unstable by definition. The half life is defined as the amount of time that half of the substance will have ceased being radioactive - normally by emitting alpha particles (helium nuclei).

They start to decay as soon as they come in to existence. Some have a half life of a trillionth of a second.

Radiological dating can be very accurate. Creationists often say its inaccurate before 12,000 years but that's only with Carbon-14 (the number indicates this is an unstable isotope) but there are lots of other isotopes which decay more slowly and can thus be used to indicate longer timescales.

Answer 5

the radioactive process shown by some special elements only, a non radioactive substance does not became radioactivity only by keeping a radioactive substance near to it,bcoz the main hero of radioactivity is neutron,which is not emmitted during the decay process but some radiations are emitted which cannot make any substance radioactive hence that banana remains unchanged, There is no special time when this process starts,but this process begin to start from the formation of the substance, this decay cannot be identifiable at the start while some timie ago it can be noticiable ,for that only we have some terms like halflife, averagelife , rate of of disinterigation etc.

Answer 6

Decay starts as soon as the molecule is formed.

You need to make the assumption that the rate of decay has always been at the same rate. No-one around 6,000 or 6,000,000 years ago with a Geiger counter. Also measuring ½ lives can be quite tricky , I know of a mammoth whos leg was dated 10,000s of years older than his stomach .

Polonium Halos can be best described as a mystery that seems to contradict 99.9% of all other evidence. The idea that we should allow the 0.01% to overrule the 99.9% is absurd.

Answer 7

Radioisotopes are formed by a variety of means: stellar fusion, cosmic ray bombardment, and decay of other radioisotopes being the most common. The decay is an intrinsic property after formation.

For radiodating, it it not from the formation of the isotope, but incorporation.

Carbon-14 is created in the atmosphere by cosmic ray bombardment of nitrogen-14. As trees grow, the incorporate the carbon into the outer living rings, then it starts decaying. The ratio of C-14 to C-12 informs you how much decay has occurred.

When rocks are formed from volcanoes, crystal form as they cool. Until they are cool, any gases inside them escape, so they are poor in argon. Potassium-40 decays to to argon-40. Argon is a gas. If you heat a crystal, it will release argon gas. This gas formed after the crystal cooled. You determine how much potassium-40 remains compared to the gas liberated to get the date the crystal formed.

These are simple versions of the techniques. There are more refined versions, and many other isotope comparisons that are used for dating.

Answer 8

All radioactive materials have a start date.


For example carbon-14 is created in the upper atmosphere by the conversion of nitrogen by cosmic rays.

http://www.nec-pj.com/products/dlpcinema/2500/index.html

And more recently by radiation from nuclear explosions and power plants.

So any living thing is constantly exchanging the carbon in it's body that has a pretty static (until the next nuclear text explosion) percentage of C14. When it dies it stops taking in new carbon, so the C14 does not get renewed and it just decays, allowing for the organism (or byproduct) to be dated pretty accurately, within certain limitations.

http://en.wikipedia.org/wiki/Carbon_14

Answer 9

The instant they are created (don't twist that :P ), if they are radioactive they will continue to be radioactive until they become stable.

The age of the element in whole is only determined by the ratio of radioactive element and the daughter material - the stable material produced during the process of shedding alpha/beta particles.

Hope this helps.

Answer 10

Why are you asking a physics question in R&S? Atheists don't know everything, we never said we do; theists are the one who can attribute everything to a higher power and claim to know all. Just because we're not professors in all aspects of science doesn't mean atheistic beliefs are wrong; are you a Dr of divinity by any chance?

I'm a biologist. It's out of my scope but from what I remember, they have radioactive properties once they come into existence. It's the ratio of expected radioactive:normal atoms where we can estimate the age of something.