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Sub-atomic Particles Used To Map Pyramid
firegate writes "Yahoo News is reporting on a pyramid-mapping project focusing on an ancient Aztec site in Teotihuacan, Mexico. Scientists are attempting to map an ancient pyramid by detecting muons - sub-atomic particles which are left as remnants of ancient cosmic rays. A similar method was used to scan Egypt's Khephren Pyramid in the 1960's."
This can only mean that they broke the Stargate and are looking for a replacement.
<cantresist>In the meantime, I welcome our new Goa'uld overlords.</cantresist>
Anybody able to discern useful details? Does it work by detecting latent muons in the Pyramid, that spontaneously "activate" and get knocked out? Or does it measure the muons that make it THROUGH the pyramid at that moment (from space), and determine from that the density of the material (since solid rock will absorb more muons than alternating rock and air-filled chambers).
DiscDividers tabbed plastic CD dividers: divider cards f
Come to think of it, it might have been useful in my old house...
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity.
This was on my Physics undergraduate course; a rather nice technique. Releated resources from my lecture notes give:
An abstract, a presentation on applying similar techniques to volcanoes, a citation [L. Alvarez et al, Science 167, 832 (1970)] (accessible only to subscribers of Science, I'm afraid), a Physics Today article, a useful paper.
is the conference where the experiment was originally proposed.
"The method is more accurate, cheaper, and more versatile than X-rays but has only been developed in recent decades due to advances in sub-atomic physics."
So would using this method be safe for living things? Perhaps airports can use lifesize scanners like in the movie Total Recall.
Life is not for the lazy.
It's even mentioned in the article the editor cites. *sigh*
The culture of Teotihuacan predates the Aztecs by a few hundred years. It climaxed around 500, went under around 600 (my sources say 700). The so-called Aztecs arived around 1200 and gave the site its name, but that's the only Aztec connection to Teotihuacan.
The system works a lot like a CAT scanner, where the absorption of penetrating radiation is measured over a variety of different paths through the object to be scanned. The only real difference is that the radiation is muons rather than X-rays (less easily absorbed, thus able to provide detectable signals through a hundred meters of rock - you should see what Fermilab uses to absorb muons so they can do neutrino experiments) and the source is natural. If you had enough money you could make your own muon source and scan the thing yourself, but when nature has been so obliging there's really no great need.
Time is Nature's way of keeping everything from happening at once... the bitch.
Muons are created high above the earth when cosmic rays interact with matter up there. They shoot out from those reactions at velocities near light speed. Because they are traveling at such high velocities, their lifetimes are extended as predicted by special relativity. Instead of nearly all decaying within a tiny fraction of a second, many of the muons exist long enough to travel down and reach us. They are a few seconds old--I think it is a few seconds; it might be less--when they reach us. They pass through objects on the surface of the earth at about the rate 1 / second / cm^2.
Muons can react with matter, but such interaction is very unlikely. If the matter is denser, such as stone, they are more likely to interact. By placing detectors inside the pyramid and counting muons coming from overhead for a long time, the scientists can estimate how much matter. They have another estimate of the matter is there by comparing to the number they would expect if they had passed through air. If that experimental estimate of the matter present is somewhat less than the expected amount based on the thickness and density of the pyramid above the detector and the density of the stone, there much be less stone than expected, possibly due to a secret chamber.
I hate to be political, but I was disturbed by the mention in this article about the use of technology in archaeology of the "War on Terror." Does everything have to be justified by that now? What happened to scientific inquisitiveness? I know that there are practicalities to deal with, but that's ridiculous. Scientists don't need to spend time justifying their research as aid to the war on terror.
There's a similar project at the University of Texas at Austin. It aims to image Mayan pyramids in Belize.
They have a fairly sparse website, but there's a quite good PDF of a slides from a talk that Roy Schwitters (former director of the Superconducting Supercollider) gave.
The basic concept is similar, except our detectors use modern HEP technology. Our detector is smaller and more versatile than the one in the article. The smaller detector will permit us to use it in a harsh enviroment. We plan to use it in a unexplored pyramid (still buried) in La Milpa, Belize. Read: in the middle of the jungle, as opposed to a well studied pyramid. It is going to be exciting!
"There is no teacher but the enemy."-Mazer Rackham
Quite contrary, it did work, but the results weren't interesting. Nothing new was found in the pyramid. Go read the paper.
"There is no teacher but the enemy."-Mazer Rackham
"Teotihuacan is up there with Rome, one of the biggest pre-industrial cities in the world. Constantinople is also maybe there but no Chinese city was of this magnitude. Egypt didn't even have cities," Manzanilla said.
Rome had over a million inhabitants at its peak in antiquity, and Constantinople just about the same by the time of Justinian according to most sources, and even those who lowball the populations of both places put them no lower than 400,000. Even classical Athens had 300,000 residents, and second-century Xi'an in China had at least 400,000 during the time Teotihuacan was inhabited with 150,000 according to the article.
Yes, it's a very large city for antiquity, but it's far from the largest.
Incidentally, one might quibble with the definition of a "city", but Memphis in Old Kingdom Egypt had a population of 30,000, which was the largest settlement in the world at the time. I think we can safely call that an Egyptian city.
And the brethren went away edified.