Scientist refute carbon dating

Most of the thousands of carbon dates from archaeological sites from the Middle-to-Upper Palaeolithic era are wrong, say scientists, perhaps even as many as 90%.As a result, archaeologists can agree on the history of this era only in the broadest of brushstrokes.Tom found himself drawn to the quantitative side of archaeology to help fill in those details.

Scientist refute carbon dating Erotisch webcam schweiz

“We know that it is older than Christendom,” he wrote, “but whether by a couple of years or a couple of centuries or even by more than a millennium, we can do no more than guess.” The fog began to lift in the middle of the twentieth century, when US chemist Willard Libby and his colleagues showed that all formerly living things bear a clock powered by radioactive carbon-14.

Organisms incorporate tiny amounts of this isotope as they grow, and they maintain a constant ratio between it and other, non-radioactive, carbon isotopes throughout their lives.

After death, the carbon-14 decays with a half-life of about 5,730 years, and the dwindling ratio serves as a time stamp.

Libby's team proved the accuracy of this 'clock' on objects of known age, such as Egyptian mummy tombs, and bread from a house in Pompeii, Italy, that was burned during the eruption of Vesuvius.

He concluded that they belonged to a Roman-era witch or prostitute.

“He did a good job of excavating, but he interpreted it totally wrong,” says Tom Higham, a 46-year-old archaeological scientist at the University of Oxford's Radiocarbon Accelerator Unit.Within 30,000 years, 98% of the already vanishingly small quantities of carbon-14 in bone is gone.And carbon-14 molecules from surrounding soil start to seep into the fossils.At university, he planned to study geography and glaciology, but switched to archaeology after excelling in an introductory course taught by his father that he had signed up for on a whim. “I got less and less interested in archaeology because it was so subjective and woolly.” The reasons for that woolliness were partly technical and partly historical, dating back to before the Highams' time.Archaeology before carbon dating relied on two principles: older things are buried beneath younger things, and people with cultural ties make similar-looking objects, such as stone tools. In the early nineteenth century, the Danish historian Rasmus Nyerup wrote that most of early human history was “wrapped in a thick fog”.It might even explain why humans survived and Neanderthals did not.

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