Questions about the radiocarbon dating of the Shroud of Turin Paolo Di Lazzaro ENEA, Chief of Research Vice director of the International Centre of Sindonology General Meeting of the International Centre of Sindonology Chambéry, 5 May 2018

Carbon dating the Shroud of Turin, a troubled decision In 1984 STuRP finished a follow-on test protocol, and gave Turin a list of 26 tests. #6 Carbon Dating. In 1986 after 2 years of political maneuvering, a meeting was held to plan radiocarbon dating, the only test accepted. The plan specified seven labs but only a single sample to be divided. In 1988 the long sought Carbon dating was accomplished. The single sample was taken adjacent to the Raes sample of 1973, arguably one of the most contaminated places on the Shroud. This sample was divided among the three AMS labs (Oxford, Zurich and Tucson in Arizona) under the supervision of the British Museum.

Shroud sampling, 21 April, 1988

Shroud sampling, 21 April, 1988

13 October, 1988. Press conference Prof. Edward Hall Dr. Michael Tite Dr. Robert Hedges Scientists marked their finding with an exclamation point as if this was to be the last word. A certain degree of hubris?

Immediate, worldwide echo Most scientists just shrugged and accepted the date. Support and interest in Shroud research declined.

Results are published in Nature, on Feb. 1989 Conclusive? Science is a relay race…

It is difficult dating textiles even by today’s technology

All stays quiet for 22 years, until 6th May 2010 in Frascati… Prof. Riani talking at the workshop IWSAI, Frascati, 2010

Robust statistical analysis Results: 1) statistical evidence that Arizona only analysed A1. 2) there is a significant trend of the age along the longitudinal coordinates.

December 2010, seven months after the Riani’s talk at Frascati

December 2010, seven months after the Riani’s talk at Frascati

Ut breviter dicam The age of the linen of the Shroud of Turin is uncertain, because the 1988 radiodatation provides heterogeneous results, probably due to a contaminant that was not removed during the cleaning procedures prior to the AMS measurements. The robust methods of statistical analysis by Riani et al., made possible by the today’s CPU computing power, allowed to discover that one of the 4 pieces given to the Laboratories (namely, one of the two pieces given to the Lab of Tucson, Arizona) was never dated, contrary to what stated in the Nature paper: this fact was kept secret for 22 years and casts a shadow on the good faith of the laboratories involved.