A team of scientists, which includes Lumiere Technology co-founder Pascal Cotte, has found a bigger mystery than Mona Lisa's smile. Through the use of the latest light technology, which is purported to have the ability to penetrate into the painting more than any other previous technology, the team discovered that the painting hides a far bigger secret.
Mr. Cotte describes the Layer Amplification Method (LAM) technology: "We can now analyse exactly what is happening inside the layers of the paint and we can peel like an onion all the layers of the painting. We can reconstruct all the chronology of the creation of the painting."
After "projecting a series of intense lights", a camera measures light reflections on the painting. The team uses these measurements to determine the reconstructions.
The team's findings however may dispel many of the widely accepted theories about the painting. The 'Mona Lisa' is believed to have been painted by Leonardo Da Vinci between 1503 and 1517, between Italy and France. The woman on the painting is said to be the wife of a silk merchant from Florence, whose name is Lisa Gherardini.
According to Mr. Cotte: "The results shatter many myths and alter our vision of Leonardo's masterpiece forever.
"When I finished the reconstruction of Lisa Gherardini, I was in front of the portrait and she is totally different to Mona Lisa today. This is not the same woman."
So who is this mysterious woman who may have been the original Mona Lisa? Or even women?
Mr. Cotte spoke of finding a couple of other images, one of which is an image that is larger in size around the nose and head but with smaller lips. The other image calls the Madonna to mind and has what looks like a headdress of pearls.
Other experts, however, believe that the Mona Lisa is still the same woman coming through the evolution of an artist's creative stages.
Emeritus professor of the History of Art, Martin Kemp, from Oxford University says:"They [Cotte's images] are ingenious in showing what Leonardo may have been thinking about. But the idea that there is that picture as it were hiding underneath the surface is untenable.
"I do not think there are these discrete stages which represent different portraits. I see it as more or less a continuous process of evolution. I am absolutely convinced that the Mona Lisa is Lisa. "
Andrew Graham-Dixon, an art historian who made the BBC documentary 'The Secrets of the Mona Lisa', studied historical documents on the painting and says of Mr. Cotte's theory: "I have no doubt that this is definitely one of the stories of the century.
"There will probably be some reluctance on the part of the authorities at the Louvre in changing the title of the painting because that's what we're talking about - it's goodbye Mona Lisa, she is somebody else."