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Older than the earth it self.
- Thread starter AlphaMale
- Start date
Okay. See, I don't know anything about this stuff. That's why I'm a music teacher.
Let me get this straight. Atomic fusion and fission hit the "reset" button so-to-speak?
Joe
This confuses me a little bit. How do we know for sure that the radio active element decays at a constant rate? It take so long for it to decay. Isn't it possible that the decay rate slows down over time?
This is something that has always been floating around in my mind, but it never really came up in day-to-day conversation.
Joe
hm... it's always been interesting to me just how flummoxed and excited people get when they discover really old stuff.
seriously, isn't this what grandparents are for?
seriously, isn't this what grandparents are for?
This is certainly a valid question.
A nucleus is a quantum mechanical system. It cannot "age" gradually like Dick Clark, but can only change from one state to another in an abrupt jump, a quantum leap if you will. Those jumps have to be associated with the capture or emission of a photon or some other particle. There are known cases of pure photon emission, but if it is anything but a photon, then it would simply be classified as a straightforward decay.
The "aging" of an isotope would be observable as a mixture of distinct states. If those states had different decay properties such as half life, other decay properties such as the energies of emitted gamma rays would also have to change. Since we have extensive catalogs of gamma spectra, an isotope with a sample-dependent spectrum would stick out like a sore thumb, as if the sample contained an undiscovered isotope.
Make sure you get your tuxedo dry-cleaned for your trip to Stockholm.
Naturally, there are some "exceptions to the rule" involving effects that are quite well understood. Part of the schtick of isotope dating is choosing an isotope that is trusted to have a constant half-life.
This is certainly a valid question.
A nucleus is a quantum mechanical system. It cannot "age" gradually like Dick Clark, but can only change from one state to another in an abrupt jump, a quantum leap if you will. Those jumps have to be associated with the capture or emission of a photon or some other particle. There are known cases of pure photon emission, but if it is anything but a photon, then it would simply be classified as a straightforward decay.
The "aging" of an isotope would be observable as a mixture of distinct states. If those states had different decay properties such as half life, other decay properties such as the energies of emitted gamma rays would also have to change. Since we have extensive catalogs of gamma spectra, an isotope with a sample-dependent spectrum would stick out like a sore thumb, as if the sample contained an undiscovered isotope.
Make sure you get your tuxedo dry-cleaned for your trip to Stockholm.
Naturally, there are some "exceptions to the rule" involving effects that are quite well understood. Part of the schtick of isotope dating is choosing an isotope that is trusted to have a constant half-life.
To wich ill add there are isotopes with very short Half-lives like radon-222 wich is 3.8 days.
Okay. See, I don't know anything about this stuff. That's why I'm a music teacher.
Let me get this straight. Atomic fusion and fission hit the "reset" button so-to-speak?
Joe
Not exactly, but so-to-speak a radio active element emissions can "activate" other elements wich have a possible radio active isotope form.
So how does an Atom get all it's particles back?
How can we tell if something is 65 million years old or just his atoms are.
How can we tell if something is 65 million years old or just his atoms are.
Well you actually cant tell that exactly, but there are 2 choices its either that old or even older.
Can I be made of 65 million year old atoms? And then when I die Carbon dating says I've been dead for 65 million years?
Erm no, carbon 14 half life is 5700 or 5800 years. But since were all from earth and the materia cant be created or destroyed i think it is safe to say that we all are made at least partially of atoms that are at least 4.45 billion years old (wich is the age earth is believe to be).
Better yet, Potassium-Argon dating (that has a really long half-life.)
Is it because things don't start to decay until you've died?
or what?
how does it work?
(I'm not a creationist by the way) I just don't understand how they know whether something is really old by Potassium-Argon dating? How can you tell if something is really old or just the atoms in it are?
The fact is that you cant "tell" yuo can aproximate it by logic. Half life is the time it takes (I.E.) half the amount atoms in nugget of uranium to become lead. If you know the rate at wich a half life single period happens and you can tell how many atoms are in the so called nugget of the original element and the amount of atoms of the byproduct of its decay you can tell how much time it has been emitting radiation. And those isotopes have been emitting since their creation as such kind of particle.
They emit as long as they remain as a radiactive isotope regardless of the biological interaction we call life.
Crazy, Haha sorry for asking all these questions I'll ask one of the biology teachers on Tuesday. But do they not start omitting radiation until we form or something? How do we know how long ago something was around and not how long ago the atoms have been around?
Thats something i wonder myself too. Guess it has to do something with the carbon cycle wich im not familiarized with.
