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Speaker 1: Get in Touch with Technology? What textfrom hofks dot com.

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Speaker 1: Hey there, and welcome to text UFF. I'm Jonathan Strickland,

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Speaker 1: your beloved host, and I'm on my own today. So uh,

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Speaker 1: I will not be throwing it over to anybody because

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Speaker 1: they won't be able to talk because they won't be here,

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Speaker 1: as opposed to the normal reason where I just talk

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Speaker 1: over them. So today I wanted to talk about something

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Speaker 1: that was sent in as a listener request. In fact,

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Speaker 1: this was sent in over Twitter, and uh, this comes

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Speaker 1: from nikkil Cardale, and I do apologize that I'm sure

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Speaker 1: I mispronounced your name, but uh, the request was could

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Speaker 1: you do an episode explaining this carbon dating is pretty useful?

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Speaker 1: So this effect seems relevant and uh Cardale actually uh

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Speaker 1: commented on and and included another tweet from real scientists

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Speaker 1: that included an article titled will our fossil use ruin

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Speaker 1: our ability to use carbon dating as a scientific tool?

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Speaker 1: This is really fascinating the idea of using carbon dating, uh,

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Speaker 1: and how that that method might be in jeopardy because

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Speaker 1: of the use of fossil fuels. So I thought I

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Speaker 1: would go into that explain what carbon dating is and

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Speaker 1: why it might not be an accurate means of telling

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Speaker 1: how old something is after too long. So going into

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Speaker 1: the article, it's about how the enormous amount of carbon

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Speaker 1: emissions we generate could make carbon dating and unreliable means

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Speaker 1: to determine the age of certain types of materials. But

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Speaker 1: to understand how that's possible, we need to know how

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Speaker 1: carbon dating works first, So we're gonna do a carbon

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Speaker 1: dating one oh one. Now, the first thing that we

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Speaker 1: have to talk about is carbon fourteen. So the fourteen

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Speaker 1: in carbon fourteen tells us it's an isotope of carbon.

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Speaker 1: This particular isotope must have eight neutrons because carbon has

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Speaker 1: six protons. You can change the number of neutrons in

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Speaker 1: an atom. That's the different types of isotopes atoms may have,

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Speaker 1: But you can't change the number of protons and atom

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Speaker 1: has without changing that element. So carbon has six protons,

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Speaker 1: and if you change that number of protons, you change

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Speaker 1: the element itself. It acts reacts differently in chemical operations,

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Speaker 1: and uh is no longer carbon. So carbon twelve is

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Speaker 1: the most common form of carbon that we find. It

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Speaker 1: has six protons and six neutrons. Then you have carbon thirteen,

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Speaker 1: which is six protons and seven neutrons, and both of

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Speaker 1: those are stable forms of carbon. That means they don't decay.

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Speaker 1: So if you have carbon twelve or carbon thirteen, you

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Speaker 1: put it in a box and you leave for I

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Speaker 1: don't know, two billion years, and you come back, you're

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Speaker 1: still gonna have carbon twelve or carbon thirteen because they

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Speaker 1: remain stable they do not decay. But carbon fourteen is different.

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Speaker 1: It is a radio isotope. Radioisotopes are also known as

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Speaker 1: radio nucleides, and these are isotopes of a particular atom

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Speaker 1: that have an unstable nucleus. These isotopes undergo what we

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Speaker 1: call nuclear decay, and in that process they release some

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Speaker 1: excess energy in the form of stuff like gamma rays

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Speaker 1: and or subatomic particles. Carbon fourteen undergoes what is called

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Speaker 1: beta decay. So when it decays, one of the neutrons

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Speaker 1: in the nucleus spontaneously changes into a proton, an electron,

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Speaker 1: and an anti neutrino. The nucleus gives the boot to

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Speaker 1: the electron and the anti neutrino, but the proton stays behind,

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Speaker 1: which means the atom no longer is a carbon atom.

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Speaker 1: Since again we mentioned that atoms depend upon the number

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Speaker 1: of protons, and the nucleus. So the carbon fourteen decays

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Speaker 1: into nitrogen fourteen, and nitrogen fourteen has seven protons and

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Speaker 1: seven neutrons. Also, by the way, one of the few

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Speaker 1: stable elements that has both an odd number of protons

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Speaker 1: and an odd number of neutrons uh, and nitrogen fourteen

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Speaker 1: is stable. It makes up the vast majority of the

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Speaker 1: nitrogen found naturally unearthed, More than of the nitrogen found

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Speaker 1: on Earth is nitrogen fourteen. So radioactive decay occurs naturally

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Speaker 1: within these isotopes, and it's a spontaneous occurrence. That's really

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Speaker 1: important to remember. Carbon fourteen has a radioactive half life

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Speaker 1: of about five thousand, seven hundred years. There's some confusion

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Speaker 1: about what that means. I find in day to day

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Speaker 1: conversations with people who haven't had science in a while.

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Speaker 1: You guys who have recently had this in science class,

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Speaker 1: you're rolling your eyes right now. But for adults who

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Speaker 1: have not taken a science class in a long time,

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Speaker 1: this might require some some refreshing. So half life of

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Speaker 1: five thousand, seven hundred years, what does that mean? It

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Speaker 1: means if you have a given amount of carbon fourteen

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Speaker 1: after five thousand, seven hundred years or so, you'll have

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Speaker 1: only half of that carbon fourteen remaining, the other half

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Speaker 1: having undergone decay radioactive decay and turning into nitrogen. Now,

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Speaker 1: this doesn't mean that all the carbon fourteen will be

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Speaker 1: gone after another five thousand, seven hundred years, nor does

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Speaker 1: it mean that carbon fourteen has a full life of

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Speaker 1: eleven thousand, four hundred years or anything like that. In fact,

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Speaker 1: what it really means is that after another five thousand,

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Speaker 1: seven hundred years, half of the remaining sample will have decayed,

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Speaker 1: leaving you with about a quarter of what you started with.

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Speaker 1: And another five thousand, seven hundred years if that means

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Speaker 1: you be left with about an eighth of that sample,

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Speaker 1: and so on. Carbon fourteen exists naturally on Earth in

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Speaker 1: trace amounts. Before the nineteen forties, the carbon fourteen on

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Speaker 1: Earth was created through a natural process. Once in a while,

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Speaker 1: cosmic rays, these very high energy particles in outer space,

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Speaker 1: would collie with an atom in our atmosphere or upper atmosphere,

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Speaker 1: and this collision would end up emitting a high energy

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Speaker 1: neutron that then could collide with nitrogen atoms that are

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Speaker 1: also way up there in our atmosphere. Now, cosmic rays

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Speaker 1: are high energy sub atomic particles. They originate outside of

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Speaker 1: our solar system. Usually they're emitted by supernova of massive stars,

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Speaker 1: and these sub atomic particles are primarily atomic nuclei and

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Speaker 1: high energy protons. So this collision of the high energy

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Speaker 1: neutron with the nitrogen forces a proton to leave the

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Speaker 1: nucleus and the in fourteen changes to C fourteen. So,

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Speaker 1: in other words, nitrogen fourteen turns to carbon fourteen. So

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Speaker 1: instead of having seven protons and seven neutrons, the new

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Speaker 1: atom has six protons and eight neutrons. The proton that

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Speaker 1: was broken off from the nucleus zooms off with an electron,

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Speaker 1: so you get one proton and one electron. That means

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Speaker 1: you have an atom of hydrogen. So again what's happening

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Speaker 1: is a high energy neutron allignes with nitrogen fourteen, forces

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Speaker 1: out a proton. The proton and an electron high tail

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Speaker 1: it and honeymoon off as hydrogen, and the incoming neutron

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Speaker 1: joins the party, and now you've got carbon fourteen. So

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Speaker 1: pre nineteen forties, carbon fourteen is rare because of two reasons.

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Speaker 1: It undergoes radioactive decay, so over time it disappears and

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Speaker 1: it's produced by an event that's not super frequent, though

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Speaker 1: it's also not uncommon, so it does happen regularly enough

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Speaker 1: that carbon fourteen is replenished, but it's a very small

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Speaker 1: overall percentage of the carbon here on Earth. Now, living

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Speaker 1: things here on Earth absorb carbon through various means, and

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Speaker 1: some of that carbon is carbon fourteen. So it may

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Speaker 1: be that you know, you eat a plant and that

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Speaker 1: plant has some of the carbon fourteen in it. Now

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Speaker 1: you have some of the carbon fourteen and you And

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Speaker 1: if we know the ratio of carbon fourteen to the

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Speaker 1: stable form of carbon twelve, we can look at materials

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Speaker 1: and analyze them to see how the ratio of carbon

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Speaker 1: fourteen to carbon twelve in the material stacks up to

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Speaker 1: the standard ratio With living things, this becomes a matter

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Speaker 1: of looking at how much carbon fourteen is not there?

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Speaker 1: All right, That's it's a little confusing. Let me explain. So,

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Speaker 1: when a living thing is still alive, it accumulates carbon

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Speaker 1: at about the same rate it loses carbon. So carbon

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Speaker 1: cosmic rays produced this carbon fourteen frequently enough that the

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Speaker 1: ratio between carbon fourteen and carbon twelve remains steady. So

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Speaker 1: the percentage of carbon fourteen to carbon twelve is fairly standardized.

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Speaker 1: But when a living thing stops being alive and turns

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Speaker 1: into a not living anymore thing, it stops accumulating carbon,

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Speaker 1: so it has the carbon that it has inside of

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Speaker 1: it stays. That's it. You're not losing anymore. You're not

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Speaker 1: gaining any more except for carbon fourteen because carbon fourteen

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Speaker 1: undergoes radioactive decay, so over time, some of that carbon

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Speaker 1: fourteen starts to convert to nitrogen. So that means if

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Speaker 1: you can look at the remains of a living thing

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Speaker 1: and detect the ratio of carbon fourteen to carbon twelve,

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Speaker 1: you can get an idea of how long ago it

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Speaker 1: was that it stopped taking in carbon, as in, how

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Speaker 1: long ago was it that this lip once living thing died.

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Speaker 1: It gets a little more complicated than all that, but

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Speaker 1: here's the basic rule. If we want to be really precise,

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Speaker 1: here's the equation we use to determine the age of

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Speaker 1: a sample of material. You have an equation where you

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Speaker 1: take the natural logarithm of n F divided by n

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Speaker 1: o uh that in turn is divided by negative point

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Speaker 1: six nine three, and then you multiply it by t

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Speaker 1: uh one half, so one half t The natural logarithm

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Speaker 1: is a specific logarithm applied to this equation and other

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Speaker 1: things as well. N F divided way n O actually

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Speaker 1: refers to the percentage of carbon fourteen and the sample

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Speaker 1: compared to the amount found in living stuff today at

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Speaker 1: times one half is the half life of carbon, so

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Speaker 1: that's five thousand, seven hundred years. So it's a lot

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Speaker 1: easier to understand this if we take a specific example.

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Speaker 1: So let's say you've got a sample of some sort

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Speaker 1: of material and you have determined that there is five

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Speaker 1: percent of the amount of carbon fourteen in that material

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Speaker 1: compared to what you would find in something that is

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Speaker 1: alive right now, So you take a sample of a

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Speaker 1: living thing, and then you take the sample of the

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Speaker 1: thing you're testing. You see that the thing you're testing

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Speaker 1: only has five percent of the carbon fourteen you would

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Speaker 1: find in living things. That means you would fill out

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Speaker 1: the equation with the natural logarithm of point zero five

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Speaker 1: divided by negative point six nine three, and you multiply

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Speaker 1: that that result to with five thousand, seven hundred years

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Speaker 1: the natural logorithm at point zero five. By the way,

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Speaker 1: in case you don't want to whip out your calculator

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Speaker 1: is negative two point nine nine five seven three to

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Speaker 1: two seven three five five. If you divide that by

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Speaker 1: negative point six nine three, you get four point three

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Speaker 1: to two eight four five night. Don't dial that number.

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Speaker 1: If you take that number, the four point three, etcetera,

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Speaker 1: and you multiply that by five thousand, seven hundred years,

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Speaker 1: you end up with twenty four thousand, six hundred forty

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Speaker 1: point two years, meaning the stuff you're looking at died

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Speaker 1: somewhere around that time frame, give or take thirty two

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Speaker 1: hundred years. So somewhere on twenty four thousand, six hundred

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Speaker 1: forty years ago is when that thing no longer breathed

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Speaker 1: or lived, or however you wanted to find it. By

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Speaker 1: the way, this approach does have a limitation. Anything older

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Speaker 1: than sixty thousand years is pretty much out of bounds.

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Speaker 1: Carbon fourteen just isn't a reliable means of dating that

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Speaker 1: sort of material, and we have to rely on other methods.

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Speaker 1: So carbon fourteen, because of the decay once against two

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Speaker 1: very small amounts, it's very difficult to narrow it down

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Speaker 1: to a specific time, and if it's long enough, there

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Speaker 1: won't be any carbon fourteen in at all. All the

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Speaker 1: carbon fourteen will have decayed by then you can't use

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Speaker 1: carbon dating if there's no carbon fourteen left. So to

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Speaker 1: actually test the carbon fourteen concentration, you first have to

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Speaker 1: take the sample, uh whatever object it might be. You

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Speaker 1: have to remove part of it, and typically you would

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Speaker 1: apply some chemicals to the material, usually a very strong

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Speaker 1: acid wash and a strong base wash. That's to remove

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Speaker 1: all the contaminating materials that could end up giving you

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Speaker 1: false readings on carbon fourteen. Then you would burn the

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Speaker 1: sample within a glass container to capture the carbon dioxide

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Speaker 1: that is emitted when you burn the material, and then

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Speaker 1: you would end allize the carbon dioxide to find out

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Speaker 1: the concentration of carbon fourteen. So you can see that

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Speaker 1: this approach has a big drawback. It ends up damaging

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Speaker 1: whatever it is you are attempting to date in the

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Speaker 1: first place. And that's why some particularly high valued items

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Speaker 1: go without being tested, because the perception is that even

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Speaker 1: a small sample of that original piece would be too

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Speaker 1: much damage to to uh make on this item. So

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Speaker 1: certain items are considered very precious and there's a big

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Speaker 1: resistance to using carbon dating because by the definition, you're

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Speaker 1: going to be damaging the material. Now there's several lines

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Speaker 1: of research they are exploring possible non destructive means of

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Speaker 1: using radiocarbon dating. There's one that uses plasma oxidation and

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Speaker 1: the use of non destructive washes to clean samples of

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Speaker 1: those contaminating humic acids, which would lead to errors if

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Speaker 1: they remain behind, but those are still largely in the

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Speaker 1: testing phase and aren't the common means of using carbon dating. Also,

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Speaker 1: keep in mind that we use this method to estimate

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Speaker 1: the date of things made from organic materials, like the

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Speaker 1: Dead Sea scrolls, but this estimation is based upon when

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Speaker 1: the materials were harvested, so, in other words, whenever the

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Speaker 1: living thing that the materials came from stopped being alive,

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Speaker 1: it doesn't tell us the date of when the artifact

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Speaker 1: was actually produced. So it's possible that you could come

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Speaker 1: across an artifact like a scroll and you use carbon

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Speaker 1: dating on it and find out that the scroll material

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Speaker 1: is two thousand years old, meaning two thousand years ago

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Speaker 1: whatever the scroll was made out of stopped living, but

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Speaker 1: it doesn't tell you about the contents written in the scroll.

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Speaker 1: It's possible that the contents were added to the scroll

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Speaker 1: much after the living thing stopped being alive. Still, it's

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Speaker 1: a pretty good bet that the two are within the

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Speaker 1: same neighborhood of time, rather than someone held onto blank

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Speaker 1: scrolls for a few centuries before or finally jotting something down.

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Speaker 1: All right, it's all this is cool, But how did

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Speaker 1: we even figure out? Radio carbon dating would be a

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Speaker 1: possible way of figuring out how old something is. Well.

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Speaker 1: Some early discoveries were made in the nineteen thirties at

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Speaker 1: the Lawrence Radiation Laboratory in Berkeley, and you probably remember

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Speaker 1: that if you've been listening to tech stuff. It factored

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Speaker 1: heavily into the discussion I had with Ben Bolan about

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Speaker 1: the Manhattan Project. So Franz Curry, an American physicist, observed

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Speaker 1: something really interesting when he irradiated a cloud of air

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Speaker 1: in a cloud chamber. He used neutrons to uh to

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Speaker 1: irradiate that cloud, and he saw proton recoil tracks that

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Speaker 1: indicated something was losing protons. So he concluded that the

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Speaker 1: neutrons that he was using were colliding with nitrogen fourteen

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Speaker 1: and producing what was believed to be a form of

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Speaker 1: carbon as a result. With hydrogen being the other product

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Speaker 1: of this collision, his work was further expo or by

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Speaker 1: physicists like Tom W. Bonner, W. M. Brubaker, W. J. Burcham,

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Speaker 1: and Maurice gold Hauber. Now collectively, this laid the foundation

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Speaker 1: for the simple equation of a high energy neutron plus

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Speaker 1: nitrogen fourteen produces one hydrogen atom and one carbon fourteen atom.

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Speaker 1: Then you had Enrico Fermi. We talked about him in

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Speaker 1: the Manhattan Project, and his work showed that the cross

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Speaker 1: section of a nitrogen fourteen atom was much larger than

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Speaker 1: other materials, and that suggested that neutron and nitrogen collisions

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Speaker 1: might happen fairly regularly in nature as long as there

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Speaker 1: were a supply of high energy neutrons. Then you have

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Speaker 1: a Serge Korf, who was a physicist who was born

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Speaker 1: in Finland and whose family immigrated to the United States

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Speaker 1: in the early twentieth century. He discovered the phenomenon that

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Speaker 1: cosmic rays interact with atoms and produce high energy neutrons

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Speaker 1: in the upper atmosphere. So Faremi's prediction and corpse observation

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Speaker 1: we're starting to kind of coalesce here. The observations convinced

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Speaker 1: scientists that the neutrons themselves were not cosmic rays, because

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Speaker 1: the neutrons had a lifespan of just eighteen minutes, and

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Speaker 1: therefore a neutron wouldn't be able to survive the long

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Speaker 1: trip through space. They must have been something else first,

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Speaker 1: So they said the neutrons had to be a byproduct

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Speaker 1: of another interaction. A cosmic ray must be interacting with

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Speaker 1: something in the atmosphere. That interaction caused this high energy

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Speaker 1: neutron to be omitted, and Core hypothesized that these neutrons

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Speaker 1: could then interact with nitrogen fourteen to produce carbon fourteen

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Speaker 1: in the upper atmosphere. Now, it was Willard F. Libby

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Speaker 1: who came up with the idea that since carbon fourteen

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Speaker 1: is generated at a steady rate due to cosmic ray

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Speaker 1: interactions in our atmosphere, you should be able to use

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Speaker 1: it to measure how long something has been dead. Libby

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Speaker 1: would measure the value of carbon fourteen's half life at

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Speaker 1: five thousand, five hundred sixty eight years, give or take

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Speaker 1: thirty years, which became known as the Libby half life,

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Speaker 1: and Libby, him off, would be awarded the Nobel Prize

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Speaker 1: in nineteen sixty for his work in radiocarbon dating. All right,

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Speaker 1: so that's the history of radiocarbon dating and generally how

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Speaker 1: radiocarbon dating works. So why is it in trouble or

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Speaker 1: what could possibly be causing confusion with radiocarbon dating. Well,

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Speaker 1: there are two big things we need to talk about,

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Speaker 1: and one was one that I've alluded to a couple

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Speaker 1: of times. I mentioned that, you know, pre nineteen forties

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Speaker 1: you had a certain level of carbon fourteen that was

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Speaker 1: pretty standard. But the nuclear age really messed things up

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Speaker 1: for us. They made carbon fourteen dating a bit tricky.

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Speaker 1: Starting in the nineteen forties, we began testing nuclear bombs. Now,

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Speaker 1: these bombs released a lot of energy upon exploding, partly

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Speaker 1: in the form of high energy neutrons. You can probably

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Speaker 1: see where this is going. Some of those high energy

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Speaker 1: neutrons ended up interacting with nitrogen fourteen atoms, which meant

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Speaker 1: that it produced carbon fourteen atoms as a result. So

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Speaker 1: the concentration of carbon fourteen in priest in the wake

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Speaker 1: of nuclear bomb testing. So anything that died after the

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Speaker 1: nineteen forties actually has a higher concentration of carbon fourteen

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Speaker 1: than the stuff that died before the nineteen forties did

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Speaker 1: even know at the time of death. According to Professor Nalini,

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Speaker 1: not Khannie of the Evergreen State College. The nineteen fifties

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Speaker 1: saw a one hundred percent spike in carbon fourteen coming

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Speaker 1: into the atmosphere. In nineteen sixty three, the United States

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Speaker 1: and Russia agreed to stop above ground nuclear testing, and

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Speaker 1: the levels of carbon fourteen in the atmosphere gradually dropped

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Speaker 1: down to their normal levels. But that means there's a

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Speaker 1: blip in the carbon fourteen radar between the nineteen forties

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Speaker 1: and nineteen sixty three. So if you put yourself in

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Speaker 1: the shoes of a future archaeologist, radio carbon dating becomes

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Speaker 1: unreliable because the levels of carbon fourteen could be deceptive.

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Speaker 1: If the thing you're measuring died during the era of

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Speaker 1: nuclear testing, it might appear to be younger than you

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Speaker 1: thought because there's a higher concentration of carbon fourteen in

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Speaker 1: its sample then you otherwise would have expected. So it

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Speaker 1: may seem that something died in twenty fifteen as opposed

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Speaker 1: to nineteen sixty three. That's just an example. Now to

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Speaker 1: the article that prompted this episode in the first place,

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Speaker 1: that's a different case. Researchers published a study in the

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Speaker 1: Proceedings of the National Academy of Sciences about how the

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Speaker 1: use of fossil fuels is further making radiocarbon dating less reliable.

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Speaker 1: And this time it's not an excess of carbon fourteen.

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Speaker 1: It's actually the opposite problem. Fossil fuels have no carbon

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Speaker 1: fourteen in them because they are fossil fuels. This is

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Speaker 1: billions of years old, so they're far too old for

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Speaker 1: any carbon fourteen to remain. Remember that carbon fourteen is

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Speaker 1: decaying over time and turning into nitrogen, so eventually all

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Speaker 1: of those carbon fourteen atoms decay. So burning a fossil

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Speaker 1: fuel create releases carbon dioxide, and the carbon in that

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Speaker 1: CEO two has no carbon fourteen and it's all carbon

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Speaker 1: twolve carbon thirteen. So the more fossil fuels we burn,

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Speaker 1: the more we dilute the concentration of carbon fourteen that's

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Speaker 1: in the atmosphere. So stuff from the nuclear age tends

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Speaker 1: to look younger than it really is because of the

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Speaker 1: higher concentration of carbon fourteen. Stuff from the later ages

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Speaker 1: of fossil fuel use will look older than they really

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Speaker 1: are because carbon fourteen has been deluded. So, according to

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Speaker 1: the study, fresh organic material in twenty fifty would contain

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Speaker 1: the same amount of carbon fourteen relative to carbon twelve

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Speaker 1: as something dating from ten fifty, So you have a

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Speaker 1: thousand years of doubt in any radio carbon dated samples.

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Speaker 1: You would look at the two samples if you if

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Speaker 1: all you had were miniscule samples of two things and

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Speaker 1: one of them was a T shirt that was made

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Speaker 1: in twenty fifty, and another was a piece of cloth

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Speaker 1: that dated from ten fifty, and you did do you

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Speaker 1: carbon dating, you'd get the same result. This is not

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Speaker 1: good if you are trying to figure out how old

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Speaker 1: something is. Heather Graven, who authored the study on fossil

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Speaker 1: fuel emissions and the effect on radiocarbon dating, says that

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Speaker 1: if we were to reduce carbon dioxide emissions drastically in

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Speaker 1: the very near future, the effect on future radiocarbon dating

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Speaker 1: would be equivalent to inserting a one year error on

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Speaker 1: top of any estimation. If we don't drastically reduce emissions,

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Speaker 1: that error range will continue to grow over time. One

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Speaker 1: thing that the concentration of carbon fourteen tells us is

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Speaker 1: how much carbon dioxide in the atmosphere comes from the

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Speaker 1: burning of fossil fuels. So as we see the concentration decrease,

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Speaker 1: we know that's because proportionally more carbon twelve is being

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Speaker 1: released into the atmosphere, diluting the already tiny concentration of

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Speaker 1: carbon fourteen. So that's useful for scientists who are studying

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Speaker 1: climate change and pollution. But that's not exactly a happy story,

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Speaker 1: is it. So what are our options if carbon dating

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Speaker 1: becomes unreliable. Well, that depends on what you're trying to analyze.

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Speaker 1: If you're looking at inorganic stuff like rocks, you don't

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Speaker 1: need to use carbon fourteen in the first place. That

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Speaker 1: would be pretty much useless. You would use something else

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Speaker 1: like potassium argon dating, which is useful to estimate the

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Speaker 1: age of rocks that are a hundred thousand years old

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Speaker 1: or younger. And if that's not a big enough range,

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Speaker 1: you can actually use uranium lead dating and that will

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Speaker 1: let you estimate rocks between one point four and five

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Speaker 1: million years old. There's a lot of different options if

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Speaker 1: you're trying to date stuff. When it comes to organic materials, however,

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Speaker 1: it's a lot more tricky. Radio carbon was a great tool,

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Speaker 1: but if it becomes unreliable, we're gonna have to use

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Speaker 1: other methods like contextual clues and other items that are

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Speaker 1: helping us connect things to dates. So this is a

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Speaker 1: big problem. I guess you could argue that's a big

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Speaker 1: problem for future generations. And perhaps the records we leave

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Speaker 1: behind now are so uh so complete, they're so voluminous,

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Speaker 1: I guess is the best word, that future generations will

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Speaker 1: likely have more than enough material to determine when something

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Speaker 1: originated from our time versus earlier times. But the point

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Speaker 1: being that the way we're interacting with our world is

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Speaker 1: changing this fundamental ratio of carbon fourteen to carbon twelve,

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Speaker 1: and that means that a really brilliant means of determining

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Speaker 1: how old something is is not really going to be

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Speaker 1: an accurate measure for very much longer. So it's kind

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Speaker 1: of a bummer obviously for things that are much much

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Speaker 1: much older. Uh, it'll at least in the short term,

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Speaker 1: not be that big of a deal, especially if we

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Speaker 1: can relate it to other items that we we already

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Speaker 1: know the age of those items. It won't be as

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Speaker 1: destructive as saying we can never use radio carbon dating again.

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Speaker 1: We just have to keep that changing uh ratio of

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Speaker 1: carbon protein to carbon twelve in mind so that we

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Speaker 1: make sure we're making accurate measurements. So thank you so

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Speaker 1: much for the request. It was fun to go into that,

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Speaker 1: and obviously there's a lot more we could talk about

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Speaker 1: with various means of dating materials. So if you want

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Speaker 1: to hear more about that, I could probably get one

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Speaker 1: of the stuff you missed in history class hosts to

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Speaker 1: join me for an episode about how people determine the

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Speaker 1: age of things, especially organic materials, and we can maybe

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Speaker 1: do a full episode if that would be of interest

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Speaker 1: to you. I could probably also grab some of the

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Speaker 1: stuff to blow your mind folks to talk about this

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Speaker 1: as well. Let me know if you have any other suggestions.

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Speaker 1: You can of course write me. The email address to

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Speaker 1: contact me is tech stuff at how stuff works dot com,

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Speaker 1: or you can write me on Twitter or Facebook or tumbler,

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00:26:03,600 --> 00:26:05,879
Speaker 1: and I used the handle tech stuff hs W at

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Speaker 1: all three. I look forward to hearing from you, and

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Speaker 1: you'll hear from me again really soon for more on

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Speaker 1: this and bousands of other topics, because it has to

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Speaker 1: have work dot Com