/sci/ - Science & Math

>>14561858
Basically Carbon 14 is an instable isotope of Carbon. An isotope is an atom that has the same number of charged nucleus particule, aka protons, but a different number of neutron, which are neutral. Since it has the same valence and the same charge, it behave pretty much exactly the same on a biological level. Radioactive atoms are by design unstable, and they decay randomly into stable, less or non radioactive atoms.
Radioactive decay happens randomly on an individual atom scale, but all atoms will eventually decay. All radioactive matter isn't equally instable, so if you take a time frame long enough, you can determine how long it will take for half of the isotope to transition to a more stable state.You can't predict when it will, but you can predict how many in how long.

We take advantage of that to create a unit called half life. Its the time it takes for half of a given quantity of specific isotope to degrade into a more stable form.

Some have half lives of a few hours, others take millenia. C-14 decays into N-14 and makes up about 1 in 10^12 of all carbon on earth. Its half life is about 5,730 years, and decays at 14 disintegration per minute per gram of pure Carbon.

Radio isotopes are freely available in the atmosphere and they end up being ingested by plants and then by other living beings.
When a life form dies it stops functionning and replacing the atoms that are composing it. So all of its C-14 is "locked" in place. As time passes, the ammount of C-14 is gradually going down to 0. Using this we can deduce the age of a life form by mesuring the ammount of C-14 in it.
Its approximative but it is more precise than a guess.

Because of atmospheric nuclear test this is fucked for 1945 and onward, because those tests made a non neglectible ammount of C-14 but for dating things prior to that is kino.

Pic rel is a simulation of half life, with higher number, the mean remaining atom in sufficiently large group remain the same

>>1472899
Simulation of many identical atoms undergoing radioactive decay,

This is essentially the closest you're getting to random.