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Science

Physics and Archaeology 191

Posted by michael from the captain-caveman dept.
Guinnessy writes: "In 1960 Willard Frank Libby won a Nobel Prize for his work on radiocarbon dating, a technique that truly revolutionize archaeology. Now Physics Today magazine has an article describing how new methods are yielding more accurate dates for our prehistoric ancestors, profoundly affecting our understanding of the past. Neat stuff."
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Physics and Archaeology More

Physics and Archaeology

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  • be useful in determining exactly when "Quirky Engeneers" went the way of the dinasour? ;)

  • more accurate... (Score:5, Funny)

    by M-G ( 44998 ) on Friday October 19, 2001 @11:46AM (#2451990)
    Boy, if we have more accurate techniques, the Scientific Creationism community is going to have to come up with new excuses to explain away why things test older than they claim the Earth to be...
    • You want to know why they test older? It is because the world was created mature. The trees already had fruit on them, the animals were full-grown, not babies. In the same manner, oil and coal were in the ground. Even dinosaur bones existed at the creation of the world. Since the world was already mature, the rocks and everything that exists already had a history. So while a skull tests as 25,000 years old, it had just been made. Try to wrap your mind around that concept. It amazes me how many people can't fathom this idea.

      This concept is an idea of my own concoction and doesn't represent anyone else.



      • You want to know why they test older? It is because the world was created mature. The trees already had fruit on them, the animals were full-grown, not babies. In the same manner, oil and coal were in the ground



        It would be just as valid to claim the "world was created mature" five minutes ago, with our past memories already in place.

      • Re:more accurate... (Score:5, Insightful)

        by Heph_Smith ( 513724 ) on Friday October 19, 2001 @12:28PM (#2452216)
        And I can say the world/universe was created the day I was conceived or born.

        More importantly, if you want to argue that the world was created with a perfect history, then it is exactly the same thing as if the world developed over time. If the point of what you said is to defend creationism, then don?t limit yourself to just thinking on such a limited scale of fruits and babies. Consider the fact that if you could know the state of every atom, with its rotation, and basically every piece of energy/non-energy then you can predict the future. Given that, if we assume our big bang theory is correct, if some omnipotent force was able create things as it wanted without limitations, then it could have set the ball in motion for the universe and ultimately us (that includes what we are thinking right now), to be exactly like it wanted from the point of initial expansion. In an isolated system, it would be impossible for the future to deviate, what so ever. This includes setting the constants of the universe so that it allows us the ability to investigate the world around us without limits. And since this omnipotent force was able to foresee the future from the point of initial expansion of the universe, then it falls in quite nicely with the thought that this force still interacts with us today, while it may be just an outcome of the initial conditions.

        IMHO, this is the best way for a religion to still claim that their god created the world and universe. While we may figure out that the earth is not the center of the universe like originally defended, I seriously doubt science will be able to disprove an event that occurred before the universe was created. But to explain the fact that our thoughts are just a product of the initial conditions of the universe, would annoy people to say the least, if they really understood it of course.

        You seem to hold the idea that something could create the earth (and I assume the universe) in detail, in an instant, yet has a linier existence. Why create something to look 25,000 years old when you can just let unfold in front of you exactly as you want it in the same instant.
      • "Even dinosaur bones existed at the creation of the world. "

        For a religion with salvation being based on faith in God, I'd be pissed off that God spends all this time and effort trying to fool us into thinking he doesn't exist by doing stuff like planting dinosaur bones in the ground to test our faith.

        I'm not too jazzed about burning in hell for all eternity because I was created with a predisposition for doubting what I dont have proof of to begin with, then this dinosaur bone stuff to confuse us even more.

        Maybe if God came down from heaven and said "Here I am, believe in Me now." and I *still* didnt believe, that I could understand He wouldnt be happy about. But all this crap about trying to make it look like he doesnt exist then we're punished for all eternity because we believe he doesnt, that's way out-of-line.

        -J5K

        p.s.- Here's a theological question that's been bothering me for a while, anyone with an answer feel free to chime in.

        If Jesus died for our sins and no one believed, would it have been in vain? Would no one be saved after that? Would everyone still be saved? Would it require a second blood-sacrifice, or a third, etc, until people believed?

        • It would have been in vain as far as the people that didn't believe - but when Jesus went to Hell to reclaim the keys to the grave, He told those in captivity there about His sacrifice (all those from before His time). Those people had the choice to believe or not, as well.
          His was the ultimate, perfect sacrifice - the last sacrifice. A guiltless man paid the price for guilty mankind (think division by zero :) ).
          No more blood sacrifice is ever required again, so no, a second or a third would not ever happen.
          Jesus' sacrifice was it. Finished.

    • Re:more accurate... (Score:4, Insightful)

      by Teancom ( 13486 ) <david@noSpAM.gnuconsulting.com> on Friday October 19, 2001 @12:11PM (#2452128) Homepage
      While another response to your post asks us to believe that God *wants* us to be confused, by "planting" bones in the earth, I think that is fairly, um, dumb :-) However, there are really two seperate issues.

      1) You have so-called "Creationists" who not only don't understand how the world was created, but don't *want* to understand. "That is one of God's Mysterys and not in the realm of man". BS. Pure and utter BS. As has been said before, if God gave us curiosity, then he meant for us to use it. These people won't be swayed by *any* proof you show them.

      2) Scientific Creationists, of which I am one, believe that God is bound be the same laws of physics that we are. However, his level of technology is much, much, much, greater than ours. That presents us with the same difficulty of your stereotypical caveman trying to understand how a microwave works. We can say "this happened, and we're trying really hard to understand how, but some of this is just going to be over our heads". That isn't willing ignorance, that's humility. In other words, just because scientists a 1000 years ago didn't understand basic principles of flight, doesn't mean birds were violating the Laws of Nature.

      Now, as to the subject at hand, accurate dating of rocks. Very few Scientific Creationists (intelligent ones, that is) claim that God waved his hand and the earth sprang in being. Matter (energy) can neither be created nor destroyed. So, when creating the Earth, God used existing materials. Whether they came from this solar system or outside of it, doesn't really matter. It does mean that the rocks can be older than the Earth is. The common example used is "if you use 100 year old bricks to make a new house, is the house new, or 100 years old?"

      Anyways, I gotta go to lunch, but I'll follow up later.

      • Re:more accurate... (Score:3, Interesting)

        by Sebastopol ( 189276 )
        destroyed. So, when creating the Earth, God used existing materials.

        So who made god?

        And if you can accept the fact that he/she always existed, why can't you accept the fact that the universe always existed without him/her?

        • A circular argument, how nice :-) If you can accept the fact that the universe always existed, does that somehow disprove that there was always a God as well? I could just as easily say that it *proves* the existence of God, as there would otherwise be no "regulating" force (see Chaos Theory). But until other proof is found, both statements are bunk :-)
          • A circular argument, how nice ... If you can accept the fact that the universe always existed

            ...you only read half of my statement: i said "[existed forever without god]". i didn't make the connection conditional. and i didn't mention proof, in fact i wasn't even discussing proof. i was focusing on capacity to imagine different scenarios. it's that final leap that always interests me: the godless universe versus the godded universe. i try to get people to explain what it is that makes them choose one over the other.

            But until other proof is found, both statements are bunk :-)

            i may have misunderstood your first post, are scientific creationists agnostic?

            a friend of mine believes that Ra might actually exist, pulling the sun across the sky, but our current scientific methods don't allow us to "prove" his presence.

            And what does Chaos Theory have to do with this? There are plenty of arguments that can be made without invoking pop-physics.

            • Sorry, that was a poor attempt to reply, I will try and do better this time (I got sufficently chewed out off-line by "Croft na" that you don't have to :-)

              I can imagine both scenarios. As an avid reader/watcher of sci-fi, I can imagine *many* different scenarios ;-) I *believe* the "godded" universe is true. This belief is based on a mixture of "blind" faith, personal experience, and various interpretations of science.

              Re: both statements are bunk. I meant that without further proof, neither statement can have any meaning beyond interesting conjecture. "bunk" was the wrong word. So no, I'm not agnostic, it just came out that way.

              And Chaos Theory has nothing to do with it. My statement was based on an erroneous interpetation of the second law of thermodynamics, which, based on a link from someone else that responded, has been cleared up. If you're interested, check out: http://www.talkorigins.org/faqs/thermo/probability .html.
              See, I have a very open mind about this, and am always willing to learn something new. And, as I'm only human, sometimes I say something wrong ;-) Feel free to correct me if it ever happens again.....

      • God is bound be the same laws of physics that we are.

        Shall I bother introducing you to the contradiction of an omnipotent God being bound by anything? "What does God need with a starship?"

        I think you're just an agnostic who's still in the closet.

        • No closet here :-) One *glaring* inconsistency in "traditional" Christian belief is that Christ died for our sins, fulfilling the law of Justice (there must be reward for every action, whether good or bad (see: action/reaction on a spiritual level)). If God is omnipotent such that He can disregard all Laws, spiritual or physical, then why have His only begotten Son die? Why couldn't he wave his hand and make Justice disappear?

          One of the *major* problems with discussing religion and science with anybody, is that just saying "I'm a Christian" doesn't come nearly close to defining what I believe. Hence, quite a few responses to my post (including yours) are based on presumptions of beliefs that I don't hold. Unfortunetly, I don't have anyway of dumping my brain into yours so that you know where I'm coming from :-(

          Maybe we should both but our hands in a box of crytals and think really hard *grin*.
          • God is just. God cannot be un-just, just like me, being white, cannot be un-white (unless I go play in the mud, but that's not the same, is it). God created mankind with a freewill, because he wants us to choose him, not to simply be hardwired so. Freewill gives the possibility that we will choose to not do the right thing, thus evil is a possibility. The penalty of breaking any law of God is death. Nothing quite so nice a black-and-white choices, is there? However, there can be a substitution for your death. Beginning in the garden of Eden, God killed a animal and brought the skin to Adam and Eve to cover their nakedness. The sacrificial system of ancient Israel was set up to cover the people's sins. The Judaic laws were to show that people could not on their own be "good enough", thus needing a sacrifice in place of their own death. This, of course, was all done to show that mankind needed something more. God came to earth in physical form, and offered himself as the very sacrifice required. Remember, this sacrifice isn't required just because God made some rule that says so. The sacrifice is required because God is who he is. In fact, that is the very first way that God describes himself to Moses when asking Moses to go talk to the Pharoh of Egypt. God says to tell the Israelites, "I am who I am". God is just, so justice is required. Christ dying for our sins isn't a glaring inconsistency, it is the ultimate of consistency. God can't just wave his hand and make justice disappear. Justice is part-and-parcel of who God is.
            • Thank you for making my point :-) That's *exactly* what I was trying to say, but I think it got lost in the translation. I was attacking those that say "God is omnipotent and thus *nothing* is beyond Him, and Jesus died for our sins because the Law of Justice needs fulfillment". It's one or the other :-) Omnipotent is YAWTNC (Yet Another Word That Needs Clarification) before being used in conversation...
              • Jesus didn't have to die for our sins. It was an example for us - God was showing that even though he could wave his hand (a very supernatural concept), he decided to communicate with us on a human level - with the greatest value in humanity being life.
          • If God is omnipotent such that He can disregard all Laws, spiritual or physical, then why have His only begotten Son die? Why couldn't he wave his hand and make Justice disappear?

            If you're wondering why he did it, I'd encourage you to reread Job, or to vastly summarize: Who the fuck are you to question why god does anything. He's god.

            If you're saying why did he have to, then you're stuck in a contradiction. If he _HAD_ to do anything, he is no longer omnipotent, and thus you have to rethink your definition of god being omnipotent.

            One of the *major* problems with discussing religion and science with anybody, is that just saying "I'm a Christian" doesn't come nearly close to defining what I believe.

            Agreed. Just because you're catholic don't mean you think just like the pope, or just cause you're an asshole doesn't mean you think like Jerry Falwell. I'm not trying to attack what you believe. If it makes you happy, knock yourself out. I just found some interesting contradictions in your post and I thought I'd bring them to your attention. One of the interesting ones is the idea of a "Scientific Creationist." You may or may not be one, but the idea by itself is a contradiction. There is no science behind creationism. You could say that S.C.ism is an attempt to describe creationism scientifically, but if you've reached a conclusion (Creationism), then try to work backward with evidence supporting it, you're not working with the scientific method, and any "evidence" you may have is skewed by your bias.

            You are granted a _hypothesis_ to work from, but only open mindedly that your evidence may prove or disprove your hypothesis. But if you've concluded that you believe the Creation myth by faith, you've checked your intellectual honesty at the door of these creation related scientific discussions.

            • The Creation theory (which you call myth) requires faith, because it has not been proven.
              The Evolution theory (which I call myth) requires faith, because it has not been proven.
              I have no problems with calling either a theory, since neither has been proven. If all scientists were to use the Scientific method (hypothesis, testing of hypothesis, document conclusion) we would actually be able to make progress toward proving/disproving the two conflicting hypothesis. The problem arrises when "Scientists" go about the "Evolution of the Scientific Method"
              1) There is no God
              2) Begin using original Scientific Method

              How odd that using this method, they have not been able to form any real conclusions.

              • Re:Scientific method (Score:1, Insightful)

                by Anonymous Coward
                I'm both a scientist and a practicing catholic. My philosophy is that the existence or non-existence of God is outside the realm of science. It is simply not a question that the scientific method can answer. It is a matter of faith. Theories such as evolution and the big bang are theories, in the scientist's sense. That's different than the common usage of the word that implies some sort of great uncertainty and speculatation. To scientists, theories are the next best thing to acts - they are ideas/models/intellectual constructs that have stood the test of time and explain all the available data (no faith here, just cold, hard data). Granted, theories probably aren't the be-all-end-all truth; no one says they are. But they are sciences best explanation for phenonmena and processes. I can't put forward a testable hypothesis about God or heaven or hell or anything in the realm of faith and hope to apply the scientific method to it. What independent data would be applicable, reproducible, and unambiguous?
                As for the "theory of creationism"... My personal view of the Bible's creation story (and I think the view of the modern church) is that it is allegorical. Moreover, I don't think the point of Genesis is to instruct man in the blueprints of the creation of the Universe. To what end? I think the point is to (a) inform us that behind all the phenomena around us (no matter how we envdevour to explain them) lies God's work and (b) that because of that, all his creations (all of the universe, and us in particular as the Bible is addressed to humans) are special.
            • Dolly, what I was trying to tip-toe around saying for fear of offending the fundies, is that God isn't omnipotent in the traditional sense of the word. He *can't* just wave His hand and make justice disappear. He *can't* just say "Okay, I think I want a planet here, *poof*". See, this is what I was talking about wrt assuming what someone else believe :-)

              As for the "Scientific Creationist" part of your post, might I point something out? You are assuming there is no science behind creationism (in fact, you said so). What I believe, and what I really, truly *wish* the other "scientific creationists" believed, is that if we knew for a fact *how* the earth was created, it would not be a case of "God did it", but would instead be "He took material from here, shaped it using these techniques, placed it in orbit around Sol, then used this and...." Do you see what I mean? It's incredibly tough to get across to some people, but not everybody who believes in God believes the same way *grin* Now *that's* a shock.....
          • One *glaring* inconsistency in "traditional" Christian belief is that Christ died for our sins, fulfilling the law of Justice (there must be reward for every action, whether good or bad (see: action/reaction on a spiritual level)). If God is omnipotent such that He can disregard all Laws, spiritual or physical, then why have His only begotten Son die? Why couldn't he wave his hand and make Justice disappear?

            God requires a blood sacrifice for our iniquities. He sent Jesus to pay that price for his chosen people. Since that price is paid, he can no longer extract it from us. This is the glory of Jesus.

            God is bound by no law, but he is faithful to his promises. This is often a confusion of people.
            • Just for fun, replace the word "God" in the above post with "Odin", and "Jesus" with "Thor".

              Or perhaps a more apt substitution would be "Ra" and "Osiris"?

              Or maybe "Frank Sinatra" and "Elvis" - you make the call...

            • god is a three letter word that represents a fantasy created by an advanced hominid culture that arose about 5 billion years after the 3rd planet from the sun coalesced from matter in this star's planetary disk.

              this is often a confusion of people, too.

      • Re:more accurate... (Score:3, Insightful)

        by oddjob ( 58114 )
        I sure hope you're a troll, but in case you're not, I feel compelled to point out that your arguments are absurd from a scientific and relegious standpoint.

        First the scientific...
        You suggest that the earth may be younger than the rocks that it is made of. Plate techtonics implies quite the opposite. Any rocks you find on the surface were probably part of the molten mess under the earth's crust at one point. It is possible, I suppose, that some of the earliest pieces of the earths crust may still be around. There could even be a few pieces of material from space that are older than the earth lying around, but most of the material in question has been melted in the earth's furnace before. So you're argument for a younger earth isn't very convincing.

        Now for the religious absurdity...
        You say you believe that God is bound by the same laws of physics that we are. I don't know of any religion that would agree. If God is bound by the laws of physics, there go all your miracles. Also, when religions claim that God created the universe, they usually claim that the laws of physics are part of that creation, not a set of rules that God had to follow.
        • >You say you believe that God is bound by the same laws of physics that we are. I don't know of any religion that would agree.

          OK. Here's one: Mormonism. While many mormons may not agree, there are many that would. As for the official doctrines of the church they do not say one way or another, but do invite the possiblity in various ways.
          • If I understand Mormonism correctly, you are right. I think that they believe that they will each go on to become "gods" of their own worlds (universes?) some day.
            • That's correct. More correctly should we say: "They believe that they will go on to become *like* god one day," being that his purpose for mankind is for them to become like him one day. It sounds very blasphemous from a modern western christian point of view. However, it makes perfect sense if you understand the mormon mindset and cosmology.
              • *ding ding ding* You caught me, I'm mormon :-) I really, really, should have prefaced my previous post with "This is *not* doctrine as canonified by the LDS Church", but I didn't think enough people would know about us to make a difference. Obviously I'm wrong ;-)

                To expand a little bit on what GeekBoy said, yes, we believe the ultimate purpose of existence is to create (hence the large families ;-). And, as God is our Father in Heaven, just like fathers here on earth, He wants us to someday be *like* Him. Don't you want *your* kids to progress, grow up, and lead productive lives? That doesn't mean that your kids *replace* you. You'll always be their father. In a similar manner, He wants us to grow up.

                Btw, what I just said *is*, afaik, official LDS doctrine, however, if it isn't, then it's *my* fault, and not the church's.

                This is drifting off topic, oh well......
        • So you're argument for a younger earth isn't very convincing.

          Although I think the original poster was a little off... the fact is, earth IS made up of material that is a lot older than earth it self. Matter does not just create it self... it comes from somewhere. Of course, I do not think there would be any way of actually dating say.. magma. (What a hot date that would be... hehehehehe)


          If God is bound by the laws of physics, there go all your miracles.

          Bzzzzt! Wrong. You must consider the fact that technology beond your time is indistinguishable from magic or in this case, miracles. Show a caveman a lighter, and you will be treated as god.
        • Just because something was a "miracle" doesn't mean it was completely impossible. The archaeological and scientific community has made the false assumption for years that if an event can be proven in the context that it can possibly happen then it wasn't of God. This assumes somehow that an omnipotent God is limited by not being able to use physical means to accomplish his will, which therefore, renders him as not being omnipotent. This is the tenet upon which evolution is built. We know that the chances of life springing forth from nothing are, more or less, 0.

          However, we say that if there are billions and billions of stars and even more planets and an infinite number of universes, it becomes increasingly likely that somewhere the environment would be correct for life to exist, and, we must be that somewhere since life exists here on Earth.

          As a Christian and someone who is interested in science, I believe that God normally does use the physical laws (which are of his creation) to bring about many of the miracles that are documented in the Bible. For example, why couldn't God have used wind to part the waters, or why couldn't God have used a meteorite to destroy Sodom and Gamorrah? Those events occurring are highly unlikely but not completely unlikely. Does that mean God wasn't the utilizing nature as his instrument? Not at all. God does transcend physical law and can do whatever he pleases but that doesn't mean that he doesn't choose to abide by them.

      • Well, you're using a slightly different definition of Scientific Creationism. I'm speaking of those who come up with "scientific" evidence to "prove" that the literal creation stories are true. They sound convincing, but don't hold any water when held to the light of science.

        See the Talk Origins [talkorigins.org] web site....
        • One of the beliefs that I hold is that All Truths are Consistent. In other words, I will not, nor have I ever, used the scriptures in an attempt to "disprove" evolution. It presupposes that the Bible, in the thousands of years it has been around, has never been mis-transcribed or mis-translated, whether on purpose or accident. Now *that* would be a miracle :-) No, evolution has enough holes on it's own, according to it's own science, that I can use *that* to discount evolution as a plausible model for creation. However, this is one point where honest people on both sides can disagree, so I don't see the point in rehashing old arguments :-)
      • "Insightful"??? Mod this DOWN!

        >Anyways, I gotta go to lunch, but I'll follow up later.

        I have discovered a truly remarkable proof of Creationism, which this margin is too small to contain.
        • I have discovered a truly remarkable proof of Creationism, which this margin is too small to contain.

          Does this mean that in several hundred years, a descendenat of Andrew Wiles will prove Creationism true?

      • Re:more accurate... (Score:3, Insightful)

        by dR.fuZZo ( 187666 )
        We can say "this happened, and we're trying really hard to understand how, but some of this is just going to be over our heads". That isn't willing ignorance, that's humility.

        Well, if you're honestly trying to understand evidence (scientific evidence, that is) that's being presented to you, that's one thing, but I know a lot of people that are willingly ignorant.

        Anyway, it's well and good to say at times "I don't understand this." It's quite another to start bringing "God" into the debate because "there's no other possible explanation."

        What I really don't get is why so many religious folks can't see that their "holy scripture" has no more solid evidence for it being The Truth than the tales of Zeus and Thor that they just naturally assume are just silly old stories. If it's so easy to pass off Zeus turning into a bull as just a story, why is it so hard to accept Jesus walking on water as just a story? Could it be the social context of the believer....? Hmmmm?
        • "but I know a lot of people that are willingly ignorant".

          Man, you have no idea how much that pisses me off. God gave you a brain, use it!! Don't tiptoe around ideas, just because they challenge your faith. Either it's true, or it's not. If it is true, then someone coming up with a different theory isn't going to somehow reverse it. People who refuse to learn or read strike me as being fundamentally unfaithful. I.e., their faith is so small, they cannot stand to have it challenged. Deliberate ignorance is maddening.

          Oh, look, that's a soapbox I'm standing on :-) I better get down before someone gets hurt....

          Please note this rant isn't aimed at you (dR.fuZZo), but at those supposedly "religous" fundies that... Ahh, I was just going to go off on another rant. I better end this post here :-)

      • Re:more accurate... (Score:3, Insightful)

        by efuseekay ( 138418 )

        You sound like somebody who really wants rigority and logic in formulating your worldview, but would not take the final step of embracing the scientific method.

        Because, according to the scientific method, the jury is still out about the existence of a creator/first cause.

        I just learned recently that this form of philosophy makes you a "gnostic theist". Nothing wrong with that, of course.

      • You left out us theistic evolutionists. The basic premise being that the chance of this universe springing into existence via some random quantum fluctuations is infinitesimally small, and 99.9999% of mutations are fatal or disadvantageus to the organism. For this level of evolution to have happened in the given (scientific) age of the Earth, it must have had help.

        The real bottom line is, the theory of evolution is sound, but unprovable. The theory of creation is also unprovable. Theistic evolution is also unprovable.

        Some things will always remain theories.

        • a decent if unsatisfying answer to that is the anthropic principle (weak/strong varieties) which is that, yes, the universe could have evolved in many ways, but it evolved in the one we see today, and our existence is proof of that.
        • Sorry, I wasn't trying to list all of the possible variations on the "how did we get here" theme :-) I actually *was* a theistic evolutionist up until a fairly short time ago, and as such know exactly where you're coming from. One great thing about the Bible, is that it is almost infinetly malleable. If I am proven wrong, (and I very well might be) and someone has indisputable *proof* of evolution, then I will quite happily go back to being a theistic evolutionist. While trying to explain to some people why my faith is unshakeable, even though it is scientifically unprovable (which, btw, isn't strictly true), I generally bring up the following example. They have a theory of an all-powerful force that affects the universe, that you can't see/smell/touch. Scientists can't prove by direct observation that they exist. They call this force a "blackhole". :-) (And yes, I know it's not a direct correlation. that's why it's called an analogy, stupid!).

      • Re:more accurate... (Score:2, Insightful)

        by ek_adam ( 442283 )
        I like the sentiments expressed in The Word of God [echoschildren.org] by Cat Faber. Here's the first verse.

        Lyrics and melody © 1994 by Catherine Faber
        From desert cliff and mountaintop we trace the wide design,
        Strike-slip fault and overthrust and syn and anticline. . .
        We gaze upon creation where erosion makes it known,
        And count the countless aeons in the banding of the stone.
        Odd, long-vanished creatures and their tracks & shells are found;
        Where truth has left its sketches on the slate below the ground.
        The patient stone can speak, if we but listen when it talks.
        Humans wrote the Bible; God wrote the rocks.
      • Aren't there a few more classes of beliefs?

        3) Agnostics that find the debate amusing and feed the trolls on both sides, happy to spout off whatever keeps the thread growing.

        4) Proponents of the 'Intelligent Design' theory, who roughly propose that God (or someone) was the initial force or energy behind the 'Big-Bang' some 15 or so billion years ago and guided the outcome including the details of life on this planet.

      • Teancom, you are an interesting creature. I've known some Mormons (good people, nice food), but perhaps I've never known them closely enough to encounter this belief scheme before. For my part, I am theist, non-Christian, for what it's worth.

        There are still large numbers of people that believe in an out of nothing creation. Likewise there are significant numbers that believe that God established the universe and physical laws so it would all evolve just how He wanted from the big bang forward. This is however the first time I've heard a westerner profess that there are physical things and physical laws outside of God that God is not responsible for and can not change. (For the record this belief has been a part of some Hindu philosophies for millenia. No, I'm not Hindu.)

        The real question then is what is God's place in the universe? If He is entirely bound by the known physical laws then you run into the problem of how does God interact with universe? If God has no physical presence, then he can not interact with physical objects while obeying physical laws. This is a form of the no causal break argument, if all events in the universe can be explained entirely on the basis of physical laws then there is no evidence for supposing the existence of a God existing outside the bounds of the universe. Of course, most people say God makes miracles by shoving physical laws aside and accomplishing what He wishes, but that would invalidate your position it would seem.

        On the other hand you might argue that God interacts with the physical world solely by possessing physical form. Perhaps by being born into a mortal body or some other means, and then using that physical form to accomplish his will in a way that strictly adheres to physical law. Of course, I think most people (though perhaps not Mormons) would be very uncomfortable with the idea that every act of God could be replicated by man possessing the right knowledge and technology. Besides this just transfers the no causal break problem unto the issue of establishing the nature and existence of God's or any other soul. If God does exist in physical form then I would challenge you to point Him out, unless of course you believe He is no longer active in this world.

        For my part I am much more comfortable acting on faith that God created physical laws for the benefit of the universe, but that He can push them asunder if need be. If I have misinterpreted your position, I apologize.
  • From the article:

    At 4.1 billion years, the halflife of 40Ar is ideal for dating ancient humans.

    OK...if you're into that sort of thing.

    I prefer 'em a little younger, though.
    • well, if halflife is good for dating, what about quake and unreal?

    • <40Ar test>
      Question 1:
      How old ARe you? 40? _______
      </40Ar test>

      I swear your honor, she said she was 18...
    • "Unfrozen caveman lawyer not used to this thing called 'playing hard to get'. Me used club on potential mate, but your strange laws of today don't allow that. Me tried it once and took me 2 years to clear name."
      </joke>

  • Sometimes the oldest methods.... (Score:4, Interesting)

    by Rackemup ( 160230 ) on Friday October 19, 2001 @11:54AM (#2452034) Homepage
    .... still have modern uses.

    Before the radio-carbon dating and the physics of glow curves and AMS testing and all the other modern techniques were available, archaeologists were digging in the dirt looking for "old-stuff" to examine. It's a natural human behaviour, a curiousity to know where we came from.

    So what did people use in the old days? Their eyes and their brains. Observations and an understanding of basic anatomy, history and geology are tools that you can take anywhere, don't require an expensive lab, and never need new batteries.

    Today's technology may be nailing down more accurate dating, but human experience out in the field is still you're best place to start in an archaeological dig. While the two should compliment each other, the people who rely on machines to do all the work for them don't really understand what it means to be an archaeologist.

    • yeah, everything we ever needed to know about archaeology we learned from watching Indiana Jones :).
    • Today's technology may be nailing down more accurate dating, but human experience out in the field is still you're best place to start in an archaeological dig. While the two should compliment each other, the people who rely on machines to do all the work for them don't really understand what it means to be an archaeologist.

      My field work has suggested to me that "what it means to be an archaeologist" is basically sitting around and spouting lots of complex scenerios from rather trivial amounts of data. Whoever pushes the grandest vision gets the biggest funding and that's what determines our view of reality. I thought about going into the field at one time but was quickly discouraged. While it's an interesting (and useful) mental exercise to sit around and think up these scenerios, I think the amount of real hard knowledge that we derive from them is essentially meaningless. Fact is, pretty much all of what we know comes from written records. The rest, we owe mostly to the harder sciences (carbon dating, genetic analysis, etc). And the speculation, well, that's not so easy to test...

      Devon

    • What the "eyes and brains" can sometimes show is how the age of one site compares to another one. E.g., on one site you find iron tools in the upper layers, bronze lower down, and stone tools in the lowest level, the sequence is pretty clear. The actual ages aren't, but the order is, and depth of the layers can give some hints as to the length of each era. They when you find the same style of bronze tools somewhere else with just a few iron tools you know they were the same people, and that it was contemporary with a particular era on your main site.

      But this does not give you real dates, so you cannot compare the ages of sites left by different, non-interacting cultures. The technological level alone does not limit the possibilities much -- stone axes are probably still in use today in New Guinea.

      The only way you get real dates is when they start leaving written records. E.g., Egyptian civilizations are datable because they etched-in-stone a nearly continuous record of the years from their first cities up through Roman times, and the Roman Catholic church has kept a reasonably accurate tally of the years since. Mesopotamian civilizations would keep records for a while, but then collapse leaving gaps of unknown length, but because they interacted with Egypt you can often associate the date. But if you want to figure out when some European hunter lived, without radio-dating your only chance is to find some definite link (same kind of clothes, pottery, or equipment) as was used by people that interacted with one of the record-keeping civilizations. (The illiterate barbarian tribes really are important to history even though they don't write any -- they keep overruning civilizations grown too soft or too complacent.)
  • Indiana Jones and the Lost Particle

  • Why this is important. (Score:4, Informative)

    by Bonker ( 243350 ) on Friday October 19, 2001 @12:00PM (#2452063)
    I didn't really see a lot of new information in the article, but it did mention some radio-dating techniques I had heard of.

    What's left to consider are the reprocussions from this kind of discovery. It's important to remember that all of human social sciences... language, philosiphy, psychology... all of them will benifit dramatically from knowing not only the exact time of origin of the human species, but early human's movement patterns.

    One of the problems about human history that this kind of dating will help solve is the origin of human language. When did humans learn to speak? What languages descended from which? Why do many 'fairy tales' appear in more than one culture? Was there a single human 'parent' language that was responsible for this?

    This kind of 'early' human history dating will help us probe out these kind of conundrums.
    • The date of the origin of modern humans (aka humans with language) also has implications for academic linguistics. The current dominant school, Chomskyan, depends upon a long history. Even the 92 Ka mentioned in the article being on the short side for the innateness hypothesis.

  • anthropology (Score:4, Interesting)

    by perdida ( 251676 ) <{thethreatproject} {at} {yahoo.com}> on Friday October 19, 2001 @12:01PM (#2452074) Homepage Journal
    We developed archaeology without any carbon dating. We had to use anthropological methods tofigure out what the meaning of a bunch of stuff in a dig was, and where it came from.

    Carbon dating is a wonderful technology - it dates stuff within a range of a century or so. It enables us to confirm hypothesis made by other methods.

    A more rigid and absolute dating technology would probably enable archaeologists to fill in many of the gaps in current knowledge.

    I worry about too much reliance on an absolute technology, though. Even if you take a bore of soil and can tell the exact day when each item fell into it, you still learn nothing about trade routes, cultures, mythologies, ancient lifestyles, etc.

    This is where anthropology, an inexact science, must take the lead.
    • any good archaeological group consists of various people, of which a physical anthropologist is a required post. The science is only part of the puzzle to back-dating and understanding lost civilizations.

      Before I went into pharma, I seriously thought about going into archaeology, and taking some anthropology classes to boost my skills. (instead, I took geochemistry, and went into drugs... go figure).

    • Still, radiocarbon dating put the field on a much more rigorous footing, which anthropology seriously needed. And accurate readings can tell us about things such as trade routes; for example, lead isotope analysis can reveal where the copper in a copper tool came from, something which has revealed a startlingly complex trading system in ancient societies of both the old world and new. Stable isotope analysis of skeletal remains can tell us about diet and lifestyle.
    • Plus, the carbon-14 ratio is pretty much shot these days, thanks to decades of nuclear testing.

      You might be surprised, as well, by how exact a science anthropology can be. In many cases, written works up to 1500 years old have been more accurately dated, and with a smaller range of uncertainty, through handwriting analysis.
    • What you're saying here is that historically, we have used a deductive approach, generating theories and the confirming them with our technology.

      I worry about too much reliance on an absolute technology, though. Even if you take a bore of soil and can tell the exact day when each item fell into it, you still learn nothing about trade routes, cultures, mythologies, ancient lifestyles, etc.

      This only becomes a worry if you are still working on the inductive approach. When you have accurate enough data in large enough quantities, you can use a deductive approach to generate your theories from the data itself. In the presences of such data, this can be very effective. You can take that soil, find when every item fell into it, and use that to guess at trade routes, rather than guessing at trade routes and then using the bore to see if you were right.

      Just because we developed archaeology without carbon dating and then used carbon dating to verify the theories of previous archaeological work doesn't mean that's the best way to do it. Just because it's a different approach doesn't mean it's any worse then then "anthropological" approach. The best results will surely come of combining anthropology and technology (and, more than likely, deduction and induction), but the order in which they are applied may shift. Times change, technologies change, and sometimes we have to change our ways of thinking in order to keep on doing better.

      Just a thought.

      -Puk

  • Dating Accuracy (Score:3, Interesting)

    by under_score ( 65824 ) <mishkin@berteig. c o m> on Friday October 19, 2001 @12:02PM (#2452080) Homepage
    One thing this article fails to mention is that when these dating techniques are used, they often give wildly varying results for a single sample often with a spread of 2 orders of magnitude!!! Another interesting point is that all the radioactive dating methods are based on critical assumptions about our earth which in some cases (Carbon-14 in the atmosphere) have been proven wrong. I'm _not_ a creationist - I believe that if anything the creation story is meant to be an allegory of some sort. So I don't pay much attention to creationist rants. I have read several good books which address these issues, particularly as the related to evolution and archaeology. On is: Shattering the Myths of Darwinism [oomind.com] (thats a review of it). It discusses in scientific detail what is wrong with the radioactive dating methods both theoretically and in their application. I highly recommend the book even though I am not truly qualified to assess its arguments (IANAS(cientist)).

    • Re:Dating Accuracy (Score:5, Insightful)

      by Copid ( 137416 ) on Friday October 19, 2001 @12:34PM (#2452237)
      You know, I hear vague references to the "critical assumptions that have been proven wrong" over and over again, and I've never heard them adequately explained. Most of the "critical assumptions" the young earthers point to are things like "the speed of light is a constant from any frame of reference". I followed your link to the review of that book and read this quote out of it:

      No one has ever bred a new species artificially--and both plant and animal breeders have been trying for hundreds of years, as have scientists.

      I've heard this one before too. And it's wrong. Way wrong. There are several observed instances of speciation (especially in the world of botany). A good easy read to start with can be found at the Talk.origins Speciation Faq [talkorigins.org] if you're interested in the background and some references to real papers on the issue. I'm sorry, but any book published after 1915 or so that claims that scientists and plant breeders have never been able to come up with new species is blatantly ignoring established facts and probably not worth your time.

      • Wow! Great reference - thanks. As for the assumptions part, they are described in detail in the book, but the one I glancingly mention is basically that C14 dating is based on the assumption that the amount of C14 in the atmosphere is in a steady state (consumed by living organisms at the same rate that it is being created in the upper atmosphere). This assumption is wrong. Here is a reference to a more complete description of this problem and others: The Pitfalls of Radiocarbon Dating [varchive.org]. I don't have convenient references for the other radioactive dating methods (Potassium-Argon, Uranium-Lead, etc.), but the book I mentioned in my other post does have complete references. I don't have the book with me so unfortunately I can't provide those references here.
      • There are still critical assumptions that have yet to be proven right. For example: do we have a scientist from 15,000 years ago confirm that the rock is in fact 15,000 and that our measurement is working? We are assuming that how a rock ages over the past ~200years will age the same way for the next million years.

        • There are still critical assumptions that have yet to be proven right.

          Actually, these aren't assumptions, they're theories. Inevitably, all our knowledge of the distant past is going to depend on theories and conjectures. The radioisotope method of dating has been endorsed by a Nobel Prize, which certainly does not prove it but lends assurance to laymen that it has some plausibility.

          Until someone comes up with evidence from some more reliable technique that contradicts radioisotope dating, it makes sense to use it to enhance our picture of the past.

          Certainty is not one of the things that theories can guarantee. Ultimately, all you can say is that radioisotope dating is consistent with other things we know about the past. In the absence of direct observation, consistency may be as close as we can come to the truth.

    • It discusses in scientific detail what is wrong with the radioactive dating methods both theoretically and in their application.

      There are ways [talkorigins.org] to get better answers.

    • Re:Dating Accuracy (Score:5, Informative)

      by Anonymous Coward on Friday October 19, 2001 @12:52PM (#2452315)
      I'm a geologist and I use some of these techniques fairly regularly (40Ar/39Ar, U-Pb, 14C, ams cosmogenic dating). Most often, anomalies in the ages you get are most readily explained by geologic uncertainty rather than gross flaws in the techniques themselves. Sloppy field work and sample collection/documentation can get you in trouble when you try and interpret the geochronology. Also, non-idealities of the materials we use to date and other factors come into play. The dating techniques are sound, the "critical assumptions" you seem to question regarding the mechanics of calculating a radiometric age and the theory behind it really come down to radioactive decay and our technical ability to measure isotopic ratios very precisely, both of which are far from dispute. The diffuculty is in interpeting the resulting ages in a meaningful way. For instance, fluid infiltration and other processes often impart "extraneous argon" to a sample that results in an anomalously old 40Ar/39Ar age. We can analyze the
      isotopic data to see if the extraneous Ar is there and we can look at the minerals and the geologic context of the sample and assess the likelihood of it. But unless we do those things throughly, we can misinterpret the isotopic data and thus the age of the sample. The isotopes don't lie, but we can be fooled.

    • Re:Dating Accuracy (Score:3, Insightful)

      by kisak ( 524062 )

      The problem with books like "Shattering the Myths of Darwinism", is that there exists no "Darwinism" as these books wants you to believe. There do exist a very valuable work by Darwin, and there exist many scientists who believe Darwin was mostly right. These scientist engaged and are still engaged in discussions with scientists who do not agree with their view -- both on details and on the more fundamental views (but no real scientist is going to tell you they can prove God's existence or other metaphysical /religious matters). This is what science is all about.

      But books like these want you to think there is some sort of conspiracy, or that science have been high-jacked by the (evil) "Darwinist". Creationists attack each evidence for Darwin's theories and end up by saying, "see, again there is reason for doubt -- the Darwinists views are built on an illusion." The problem is, all these methods were not developed to prove Darwin is right. The physics behind carbon dating was not developed with Darwin in mind, but then some smart guy finds out, "these methods can give us answers also in archeology!". Any new method will be compared with estimate from previous methods, and any new method (new radioactive isotopes for instant) will have the potential to invalid older methods (and conclusions built upon them) and make scientist re-evaluate what is the most thrust wordy theory.

      When two methods estimates don't compare -- one or both is wrong (or interpreted wrong) -- and scientist in the field will be all fired up to unravel the mystery and to win that Nobel prize. The greatest mistake is to believe scientist in general are disappointed to find out the accept theories are no good -- this only gives them the opportunity for making a new theory that will make them famous (yeah!) and also extend human knowledge (you are a researcher, and this is your goal). A "scientific theory" that God created the Universe in 7 days, is hard to "prove" but more importantly, not very interesting. (An all mighty God could have created the Universe one second ago with me and all my memories with it, but so what?) Metaphysics is best left to the philosophers.

      To discuss more details; yes, physicist and geologist do know about experimental errors or experimental limitations. Two orders of magnitude is large, but is sometimes acceptable, but only as long as one are aware of the accuracy of a measurement/method. One can not invalid the usefulness of radioactive dating in a field just because the method is uncertain. The interpretation of the result is also depended on other theories like the Carbon-14 in the atmosphere ages ago. But then, some smart guy drills a hole in the ice of Greenland, and one has a new method to test these theories. And when this method fits with older theories, we believe more in them. But who knows, maybe we will get another way to find out the C14 in the atmosphere millions of year ago, that will show the theories of today are wrong. But it will be a very strange scientist who thinks this is a bad thing.

      I do not mind books attacking leading scientific ideas; many of those books are science books. But be aware of books/authors that want to convince you of something, but do not want to tell the whole story. I have not read this book, but any book that builds on the myth of "Darwinism", should be approached at least as critical as those theories we at the moment accept as the most scientific reasonble....

    • Re:Dating Accuracy (Score:3, Insightful)

      by blamanj ( 253811 )

      It discusses in scientific detail what is wrong with the radioactive dating methods

      The Creationists like to point out so-called "flaws" in dating techniques that are based on "assumptions." While they can sometimes confuse the scientifically illiterate with this terminology, there is now a dating technique that doesn't rely on knowledge of radioisotopes that is very effective in showing the foolishness of their arguments.

      Dendrochronology [shef.ac.uk] is the science of dating by the use of annular tree rings. Nothing too confusing here, it's school kid stuff. However, by piecing together the "fingerprint" of a sequence of years, we can put overlapping material from live trees and trees used in construction or preserved in peat bogs, etc. to create a calendar of the past 9000 years [sonic.net], well beyond the Creationist "age of the earth."

  • AMS facilities (Score:3, Interesting)

    by psmith ( 11508 ) on Friday October 19, 2001 @12:16PM (#2452152)
    AMS is nifty not only because of the physics involved, but as a great way to make use of accelerator labs that might otherwise be closed..

    Our lab here at Purdue, PRIME Lab [purdue.edu], is a great example of this, retooling an older tandem accelerator lab for a new use as funding for nuclear physics began to dry up, and other similar facilities around the country closed. We've even got one of the accelerators with the highest energies of any AMS facility in the US by reusing the facility in this way.

  • Perhaps (Score:1, Funny)

    by SLot ( 82781 )
    they can explain why Quirky Engineers have gone the way of the dinosaur...

  • Um.... (Score:5, Interesting)

    by KillerBob ( 217953 ) on Friday October 19, 2001 @12:25PM (#2452200)
    First paragraph in the article... and already they've lost my (suspension of dis)belief....

    ==> Traditional archaeology has not been a field that suffers science easily. Only gradually have archaeologists accepted physics as a tool for archaeological research. Perhaps as a result, the physicists who work in archaeology, their methods, and their theories, are neither well known nor numerous. Archaeometry, as the wider field of scientific archaeology is known, has no Heisenbergs or Einsteins, uncertainty principles or relativity theories. The only physical discovery to truly revolutionize archaeology has been radiocarbon dating.

    Physicists have developped ground-based RADAR technology and Echo-location technologies which are having a profound impact on the archaeological world.

    Take a look at: http://www.exn.ca/inc/demo.asp?Video=exn20011009-a cadia.asx
    (Windows media player format, sorry.)

    These RADAR/SONAR devices have drastically reduced the time it takes to locate archaeological sites, and yet they don't even mention it until the end of the article. After having clearly stated that "The only physical discovery to truly revolutionize archaeology has been radiocarbon dating."


    • These RADAR/SONAR devices have drastically reduced the time it takes to locate archaeological sites, and yet they don't even mention it until the end of the article. After having clearly stated that "The only physical discovery to truly revolutionize archaeology has been radiocarbon dating."

      They also leave out potassium-argon dating, fluorine dating, electron spin resonance dating, uranium-thorium dating, fission track dating and several more.
      • Skimmed the article a little too fast, apparently they did mention some of these. Not sure why this is all presented as new, some of these dating methods have been around for a while.
    • and that the author could have been more clear. Radio-carbon dating was a watershed change in the nature of the science. Stratigraphic relative dating has been around for a couple hundred years, but radio-carbon allowed the stratigraphic relative dates and non-stratified artifacts to be anchored by absolute dates. This caused a fundamental change in both the ability of the science to explain the past and the accuracy with which it does so. Ground penetrating radar and other remote sensing techniques streamline site-surveying, save time and labor, and vastly improve the technique of the science, but they have less impact on the scope by far than radio-carbon. Remote sensing has been around a long time in many forms, such as climbing a hill to observe vegetation patterns as indicators of subsurface artifact and feature ditribution.

  • One thing about carbon dating and other systems like it make on BIG assumption: the rate of decay has stayed constant through eons of time and massive climate changes.

    What if it hasn't stayed constant? What if it's on an exponential rate itself? What if it decayed at a slower/faster rate 1 million years ago? What if an asteroid collision (or some other massive geological event) caused a limited duration decay acceleration?

    The list can go on and on.

    • Re:Assumptions (Score:1, Informative)

      by Anonymous Coward
      > What if it's on an exponential rate itself?
      > What if it decayed at a slower/faster rate
      > 1 million years ago?

      I suspect that couldn't happen unless the balance between the strong and weak forces changed. And if that balance did change, the results would be far more catastrophic than a mere asteroid collision.

      Imagine entire galaxies unravelling into bundles of plasma - or switching off like a light switch.

      No, I don't see that assumption as a major problem.

    • The "BIG assumption" that the rate of decay is constant is based on some pretty fundemental physics.

      If you're going to say that decay rates may have been different in the past, it is up to you to at least come up with data to show why anyone should accept this, and you need to devise a theory to explain why decay rates have change (and hence show where current theories are wrong).

  • Archaeology and Modern Technology (Score:3, Funny)

    by GogglesPisano ( 199483 ) on Friday October 19, 2001 @01:44PM (#2452508)
    I heard someone say that the biggest technological contribution to archaeology in the last 50 years was the zip-lok bag.

  • carbon 14 dating and tree rings (Score:3, Interesting)

    by NaturePhotog ( 317732 ) on Friday October 19, 2001 @01:57PM (#2452567) Homepage
    One thing the article didn't really go into that I found interesting is how carbon 14 dating was found to be inaccurate. It had been assumed that C-14 decayed at a constant rate. However, a guy named Schulman studying the Bristlecone Pine trees in the White Mountains of California discovered that C-14 dates didn't match the tree ring dates. Subsequently, tree rings between living and dead bristlecones have been used to construct accurate dating back 9000 years, and it has been determined that C-14 rates do change. Read more about it on the Inyo National Forest [fs.fed.us] page.

    • Re:carbon 14 dating and tree rings (Score:1, Informative)

      by Anonymous Coward
      Actually, it isn't the decay rate that is changing over time. It's the exact opposite. The production rate of 14C in our atmosphere (due to interactions between N and cosmic rays) is changing over time. As with all cosmogenic nuclide techniques (e.g. 26Al, 10Be, 36Cl), our constraints on the production rate of the nuclide of interest is key. Dendrochronology (tree ring dating) has helped to put firm constraints on the 14C production rate going bakc 9kyr or so.
    • C-14 dating only has "reasonable" error ranges for items dated at 5000 years or less (around 1 century). If you use C-14 to date something older, say, 10000 years (or 10,000,000 years), the percentage of error margin gets significantly larger. The man who designed carbon dating (his name escapes me) explained this in his thesis which won him the Nobel Prize.

      -Ted

      PS: What cites? You know where to find them [google.com]
  • the bible tells me that there is just no way that stuff could be that old.
    hee hee.

    silly bible.
  • is that you can tell easily item one is just a s old as item two. But unless you have a way to date one of the items some other way, all you can tell is that the items are the same age, but not how old they are.

    When you are talking about artifacts millions of years old, there is no "proof" of the age of any item.

    Some scientists put together a theory of how carbon acts over millions of years (and obviously because of the timeframe involved have no empiracle evidence about the behavior of carbon over millions of years) Then they date things relative to the theory.

    Note I am not saying carbon dating is wrong, but it certainly hasn't been proven.

    • Re:The problem with carbon dating... (Score:1, Informative)

      by Anonymous Coward
      Although you do bring up a good point, you are otherwise incorrect on several levels. The good point you bring up is the need to corroborate geochronologic data with a variety of techniques. Fortunately, 14C is not the only geochronometer available and additional age constraints can be obtained using cosmogenic nuclides, electron spin resonance, themoluminescne, etc. However, to say that there is "no proof" of the age of a sample even from one geochronometer is disingenous at best. There is nothing magical about geochronology. Our theoretical knowledge of radioactive decay and our techniques for measuring isotopes are sound and robust. The trick, as you in a way imply, is our understanding of external processes that affect the systematics of the samples we seek to date and I will add our interpretation of the geologic context of what we date. As far as our understanding of those external factors as they relate to 14C, I'd say we have it nailed pretty well. First off, 14C is not used for dating
      anything over ca. 60kyr to 100kyr old. No million year stuff. You use 40Ar/39Ar and other techniques for that. As for the systematics of C over time, the things we need to know and assume are: a) production rates of 14C over time which we get a very detailed record from tree rings, etc. (b) we assume that living organisms are in radiometic equilibrium with the atmospheric reverviour of 14C, which is reasonable, and (c) we assume that after death the organismn no is no longer in equilibruim (i.e. uptake rate does not equal decay rate). After that, we just need to rely on decay and our abiltiy to measure small numbers of atoms precisely (hence ams techniques). But I must reiterate taht without good field work the best numbers you can get are pretty meaningless.
  • In 1960 Willard Frank Libby won a Nobel Prize for his work on radiocarbon dating, a technique that truly revolutionize archaeology

    doing nothing for the english language, which is still in caveman speak...

  • Pyramids (Score:3, Interesting)

    by Kraft ( 253059 ) on Friday October 19, 2001 @02:29PM (#2452709) Homepage
    Yes, this is kinda silly and kinda offtopic, but I can't be bothered to do some proper searching on the subject.

    When were the oldest pyramids in Egypt built - really?

    I saw a special on Discovery a year ago, and they said that carbon dating was estimating the pyramids to be (IIRC) between 4 and 11 thousand years old. Not too accurate, is it? Can someone explain, why there is so much doubt when estimating the age of pyramids, when they could set the age of the Egyptian pharaoh's tomb to 5730 years? And have any of these new techniques set some more accurate dates?
    • This link [hunkler.com] should give you information on the pyramids. I believe they dated the pyramids because of how they were aligned to the night sky when they were created (since the sky slowly shifts over time).

      -Ted
  • One such fossil is the Homo erectus known as "Java Man." The famous relic was found in 1891 by the Dutch paleontologist Eugène Dubois on the Trinil terraces of the Solo River in Java.
    Another is the RMS sapiens known as "Lisp Gnu". The famous relic was extracted in 1991 by Finnish programmer Linus Torvalds from a sleazy office along the Charles River in Cambridge.
    From its discovery onward, Java Man has been controversial. Even up into the late 20th century, its precise placement in the human evolutionary tree was debated, largely because of the inability to obtain completely reliable dates for the archaeological and geological context of the Java fossils.
    From its discovery onward, Lisp Gnu has been controversial. Even up into the late 20th century, its precise placement in the COBOL evolutionary tree was debated, largely because of his inability to cool his temper in the academic context of the Cambridge fossils.
    In the case of TL and ESR, the clock resets to zero when the sample is heated and starts ticking once the sample cools.
    Thus, the ESR clock resets to zero when the cathedral is heated, and starts ticking again once the bazaar cools. No more temper problems!
  • I don't have time to read the article, but wow, this is a story I've been waiting for. So many times I see other /.'ers talking about how they were individually involved with some type of research, and now it's my turn:

    One up and coming way of dating fossils uses a technique called Nuclear Reaction Analysis (NRA). You bombard a substance (in this case flint) with ions, which penetrate the sample and react with fluoride when they're at a certain depth/energy. The theory is, fluoride has only been in water since a certain time in our past, so based on how deep the fluorine is inside the sample, you know how old it is.

    Check out here [unt.edu]

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