Crosses of light under scientific scrutiny
Physics students at the Dutch Technical University of Delft spent last year finding the physical properties of these miraculous phenomena, but can they determine their cause?
Delft, The Netherlands
Since their first appearance in Los Angeles in May 1988, several hundred more crosses of light have miraculously appeared in people’s homes all over the world. From America to New Zealand, from the Philippines to Slovenia, brilliant crosses of light have sometimes appeared in the frosted glass windows of houses, hospitals and churches, when a one-pointed light source shines through the glass from the other side. Witnesses call them miracles and report healings, others travel hundreds of miles just to enjoy their beauty.
In the extensive media coverage about the mysterious crosses over the past 10 years, scientists have been asked their opinion about the ‘inexplicable phenomenon’. Occasionally, this resulted in a brief examination of a window and even briefer comments (which usually refer to ‘the special structure of the glass’, ‘dirt accumulation’ or ‘atmospheric influences’). Other than that, the crosses of light have never been thoroughly investigated by the scientific community.
In the last year, however, a more elaborate study has been carried out. At the Dutch Technical University of Delft, two third-year students, Carolynne Montijn and Hedwig Rotteveel, from the faculty of Technical Physics, have spent over 10 months on their ‘cross of light research project’. The subject was presented to them by their physics teacher. He had been interviewed for a science magazine in connection with ‘modern-day miracles’ and had become intrigued by the crosses of light, for which he had no immediate explanation.
"Secondly, we searched the internet, typed in ‘cross of light’ and discovered websites from Share International and media reports on the subject. Also, we found a videotape about the crosses made by American film editor Frances Robinson. Last, and most important, we had the opportunity to borrow a small piece of frosted glass that was cut from a window in Canada some years back which clearly shows a red cross of light. It was all we had to go on, but it turned out to be just enough for our purposes.
"We read about the theories that the crosses must be signs of some great spiritual happening in the world, but even if that were so, we thought the form of the crosses in the glass should still be scientifically explainable. So we set out to try and prove that."
"Our goal," Carolynne continues, "was not to establish the cause of the overnight change in the windows, but to find out exactly how glass can show such particular patterns at all.
"The results were quite amazing," says Hedwig. In their 110-page report, presented at Delft University in 1998, they conclude that their computer programme indeed provides a good replica of crosses of light. "Our simulation so much resembles reality that both form and size of the refractive pattern look identical to the actual cross. In other words: we have been able to simulate the cross in the smallest detail. Our conclusion is that the change from the normal form into the figure of a cross can be attributed to a change in the refractive index of the surface of frosted glass to exactly 1.561. So, as soon as light bends through glass with a refractive index of this exact number, it displays the form of a cross."
"Of course," says Carolynne, "for the sudden alteration of the shape in a window to occur, the surface of the glass somehow must have changed. As the crosses appear all around the world, it is highly unlikely that the abrupt transformation of the pattern has to do with the kind of glass used or the manufacturing process. We had this confirmed by a local glass company.
Therefore, although from the point of view of physics we have successfully demonstrated that when the light bends through frosted glass under a specific index of refraction, this particular form of a cross is seen, further research would be necessary into the actual cause of this strange phenomenon. Perhaps it would have to do with minute changes in the surface of the glass, caused, for example, by rigorous cleaning; or, theoretically, the molecular structure of the cross-windows somehow having been altered. To our minds, for this part of the puzzle there must be an equally viable scientific explanation."
From the January/February1999 issue of Share International