Physics and Archaeology

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."

Comments

more accurate...

[M-G]

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...

Re:more accurate...

[Teancom]

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...

[Heph_Smith]

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.

Sometimes the oldest methods....

[Rackemup]

.... 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.

Why this is important.

[Bonker]

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.

anthropology

[perdida]

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.

Um....

[KillerBob]

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."

Re:Dating Accuracy

[Copid]

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 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.

Re:Dating Accuracy

[Anonymous Coward]

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.