The Shroud of Turin and Technoscience

COMMENTARY: The more the cloth is investigated, the more the evidence accumulates for its authenticity.

Negative image of the Shroud of Turin
Negative image of the Shroud of Turin (photo: Register Files)

Our train was speeding up the Italian peninsula at 100-plus miles an hour.

Equipped with PowerPoints, flat screens and Wi-Fi, it was the epitome of everything techno-scientific about the modern age.

The clash, therefore, with our vacation destination pushed the irony as fast and as far as the train itself, for we were going to venerate the Shroud of Turin.

We found our hotel, and over dinner with a young fellow pilgrim, we discussed the mystery of the shroud. I had researched the purported burial cloth of Christ for many years and continue to be intrigued at how every new techno-scientific discovery adds a new dimension to its mystery.

The shroud lay virtually unknown for 1,900 years and would have been dismissed as a grubby medieval forgery if it hadn’t been for the advances of modern technoscience.

The shroud’s first encounter with the technology of the modern age was when it was first photographed by Secondo Pia in 1898. Pia was astounded, when he developed his plates, to discover that his photographic negative was actually a positive image of a man’s face. That meant the image on the shroud was, in effect, a photographic negative. 

However, it was not just a photographic negative. The unique qualities of the shroud image were confirmed in 1976, when a photograph of the image was put into a VP-8 Image Analyzer — a gadget that transforms the lights and darks in images to three-dimensional forms. An eerie 3-D image of a man’s face emerged — something that the gadget cannot produce from photographs or paintings.

“This spatial data encoded into the image actually eliminates photography and painting as the possible mechanism for its creation and allows us to conclude that the image was formed while the cloth was draped over an actual human body,” according to Barrie Schwortz, an internationally recognized authority on the shroud. “So the VP-8 Image Analyzer not only revealed a very important characteristic of the shroud image, but, historically, it also provided the actual motivation to form the team that would ultimately go and investigate it.”

The amazing discovery of the three-dimensional image prompted a team of scientists to conduct the most extensive research on the shroud in 1978: Sturp (the Shroud of Turin Research Project). The scientists spent two years preparing to conduct the tests and more than 120 hours rigorously examining the scientific qualities of the shroud.

Most of their work is published in specialist scientific journals, but an accessible summary concluded that no paint, oils or spices formed the image. The cloth was in contact with the body of a crucified man, but the scientists were unable to offer an explanation for the process of forming the image.

The Sturp investigators outlined various details that point to the shroud’s authenticity. Firstly, the crown of thorns is invariably portrayed in medieval art as a circlet of thorns. The shroud reveals it to be a cap of thorns covering the crucified man’s entire head. Secondly, the man on the shroud was nailed through the wrist, not the palm. Medieval portrayals of the wounds are almost always through the palm. Modern physiology reveals that the weight of the body would tear through the palms, whereas a nail between the wrist bones would support the body weight. Furthermore, modern physiology has shown that when the wrist is pierced, the punctured median nerve causes the thumb to move in reflex against the palm of the hand. This explains why the crucified man’s thumbs are invisible. Would a 14th-century forger have such detailed anatomical knowledge — and why would he have contradicted the traditional iconography?

From the Sturp investigation came other intriguing details that could only have been unlocked in the scientific age. Botanist Max Frei famously traced pollen common to the ancient Middle East through his investigation of the shroud, and his pioneering work has recently been augmented by Marzia Boi, who has identified the pollen as that present in the herbs and oils used for Jewish funeral rites in the time of Jesus.

Then, in 1988, a scrap of linen was clipped from the shroud and sent to laboratories in Arizona, Oxford, England, and Zurich to be dated using the carbon-14 technique. For the first time, the scientific tests invalidated claims of the shroud’s authenticity. The tests dated the shroud between 1260 and 1390. This fit perfectly with the first documented appearance of the shroud in Lirey, France, in 1353.

Despite the other encouraging evidence, the carbon-14 dating seemed to be conclusive proof that the ancient linen cloth was an ingenious medieval forgery.

However, the mystery of the shroud was not to be solved quite so easily. Further research uncovered a painting that portrayed the shroud, which predated both the documented exhibition in Lirey and the carbon-14 results. Shroud believers suggested that the fire that nearly destroyed the shroud in 1532 could have affected the carbon-14 dating, and closer examination revealed that the area from which the linen was taken for testing was not only the area handled by those displaying the shroud over the centuries, but it had been repaired by almost invisible interweaving in the 14th century.

Suddenly, the carbon-14 dating did not seem so watertight. Then, in 2012, an Italian academic who had been studying the mystery of the shroud for years released what seems to be the best theory to explain the shroud’s image. Giulio Fanti, an Italian professor of mechanical and thermal measurement at Padua University, reports that the only technique to come close to reproducing the image on the shroud is ultraviolet radiation. However, it required 500,000 volts to produce a replica only a few centimeters long. Fanti calculates that to produce an instant image the size of the shroud would require tens of millions of volts — something which is impossible to produce through natural methods.

The irony of the Shroud of Turin’s long history is that it was only in a skeptical, scientific age that the scientific technology has been available to test the shroud — and the more the shroud is investigated, the more the evidence accumulates for its authenticity.

Perhaps the techno-scientific whiz kids that created that high-speed train can turn their brilliance toward establishing how an artisan of the 14th century could have detailed knowledge of Roman torture techniques and tools, reproduce accurate physiological wounds of crucifixion, introduce pollen from the Middle East and singe a negative photographic image onto linen giving it three-dimensional imaging capabilities.

Then they must explain why an artist would trouble himself to produce such an image. If he was out to fool the faithful, wouldn’t a simple painting have sufficed?

Or they could accept that this ancient linen cloth provides what is virtually photographic proof of the resurrection of Jesus Christ.

Father Dwight Longenecker is a priest of the Diocese of Charleston, South Carolina.

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