The discovery adds new complexity to one of the most controversial relics in Christendom, venerated by many Catholics as the proof that Christ was resurrected from the grave and dismissed by some scientists as a brilliant medieval fake.
The study, which will be published on Tuesday by one of the journals of the Institute of Physics , the Journal of Optics A: Pure and Applied Optics, examined the back surface of the famous handwoven linen.
The front side of the shroud, on which the smudged outline of the body of a man is indelibly impressed, has been investigated by a multitude of scientists. But the reverse side has remained hidden for centuries beneath a piece of Holland cloth that was sewn by nuns in 1534, after a fire had blackened parts of it.
The cloth's back surface was fully scrutinized only in 2002, when the 14-foot-long linen was completely unstitched from the Holland cloth during a restoration project.
To the naked eye, the back surface of the shroud showed almost nothing, apart from a peculiar stitching which Mechtild Flury-Lemberg, the Swiss textile expert who performed the restoration work, identified as a style seen in the first century A.D. or before.
The back surface, however, was photographed in detail and the pictures published in a book by Mons . Giuseppe Ghiberti, one of the church's top Shroud officials. At the end of the restoration, a new reinforcing cloth was sewn back in place, hiding again the shroud's reverse side.
"As I saw the pictures in the book, I was caught by the perception of a faint image on the back surface of the shroud. I thought that perhaps there was much more that wasn't visible to the naked eye," Giulio Fanti, professor of Mechanical and Thermic Measurements at Padua University and main author of the study, told Discovery News.
Using sophisticated image processing based on direct and inverse Fourier transform, enhancement and template-matching techniques on Ghiberti's pictures, Fanti uncovered the image of a man's face.
Lying behind the known image of the bearded man bearing the marks of crucifixion, the new image has striking three-dimensional quality and matches in form, size and position the known face.
"Though the image is very faint, features such as nose, eyes, hair, beard and moustache are clearly visible. There are some slight differences with the known face. For example, the nose on the reverse side shows the same extension of both nostrils, unlike the front side, in which the right nostril is less evident," Fanti said.
However, the enhancing procedure did not uncover the full body image as it appears on the front side.
"If it does exist, it is masked by the noise of the digital image itself. But we found what it is probably the image of the hands," Fanti said.
The presence of a face on both sides of the shroud would seem an obvious feature in case of a fake: when making a print onto a cloth, paint soaks the cloth's fibers reaching also the back side.
"This is not the case of the Shroud. On both sides, the face image is superficial, involving only the outermost linen fibers. When a cross-section of the fabric is made, one extremely superficial image appears above and one below, but there is nothing in the middle. It is extremely difficult to make a fake with these features," Fanti said.
According to the scientist, this double superficiality could be crucial to answer the central, unanswered question of how the image of that man got onto the cloth.
Shroud History
Scientific interest in linen cloth began in 1898, when it was photographed by lawyer Secondo Pia. The negatives revealed the image of a bearded man with pierced wrists and feet and a bloodstained head.
Scientific interest in linen cloth began in 1898, when it was photographed by lawyer Secondo Pia. The negatives revealed the image of a bearded man with pierced wrists and feet and a bloodstained head.
In 1988, the Vatican approved carbon-dating tests. Three reputable laboratories in Oxford , Zurich and Tucson , Ariz. , concluded that the Shroud was medieval, dating from 1260 to 1390, and not a burial cloth wrapped around the body of Christ.
But since then a growing sense that the radiocarbon dating might have had substantial flaws has emerged among shroud scholars.
Fanti's finding matches a hypothesis postulated in 1990 by John Jackson, an American physicist who conducted the first major investigation into the shroud in 1978. Jackson speculated the presence of a faint image on the back surface of the shroud, only in correspondence to the frontal image.
The history of the cloth has been steeped in mystery. It has survived several blazes since its existence was first recorded in France in 1357, including a mysterious fire at Turin Cathedral in 1997.
Kept rolled up in a silver casket, it has been on display only five times in the past century. When it last went on display in 2000, more than three million people saw it. The next display will be in 2025.
By Rossella Lorenzi, Discovery News
Taken from:
http://catholicintl.com/scienceissues/shroud.htm