"A new definition of crystal emerged, one that is beautiful and humble and open to further discoveries. A humble scientist is a good scientist."
Dan Shechtman's speech at the Nobel Banquet, 10 December 2011.
Your Majesties, Your Royal Highnesses, Nobel Laureates, fellow scientists, ladies and gentlemen, dear family.
On April 8, 1982, I was alone in the electron microscope room when I discovered the Icosahedral Phase that opened the field of quasi–periodic crystals. However, today I am joined by many hundreds of enthusiastic scientists worldwide. I stand here as the vanguard of the science of quasicrystals, but without these dedicated scientists the field would not be where it is today. This supreme recognition of the science we have unveiled over the last quarter century is celebrated by us all.
In the beginning there were only a handful of gifted colleagues who helped launch the field. First was Ilan Blech, at the time a Technion professor, who proposed the first icosahedral model. He demonstrated, by computer simulation, that the model could produce diffraction patterns that matched those that I had observed in the electron microscope. Together we wrote the first announcement of the discovery. Then John Cahn of the US and Denis Gratias of France coauthored with us the second, modified article that was actually published first. Other key contributions to the field were made by Roger Penrose of the UK who, years earlier, created a nonrepeating aperiodic mosaic with just two rhomboid tiles, and Alan Mackay of the UK who showed that Penrose tiles produce sharp diffraction spots. Dov Levine of Israel and Paul Steinhardt of the US made the connection between my diffraction patterns and Mackay's work. They published a theoretical paper formulating the fundamentals of quasi-crystals and coined the term. All these pioneers paved the way to the wonderful world of quasi-periodic materials.
I would like to mention two other eminent scientists who are no longer with us, whose commitment to the field was of great importance. These are Luis Michel, a prominent French mathematician, and Kehsin Kuo of China, a leader in electron microscopy, who was trained in Sweden.
We are now approaching the end of 2011, the UNESCO International Year of Chemistry, a worldwide celebration of the field. In a few weeks we will see in the New Year, 2012, the centennial of the von Laue experiment which launched the field of modern crystallography. The following year, 2013, will mark the International Year of Crystallography. The paramount recognition of the discovery of quasi-periodic crystals is, therefore, most timely.
The discovery and the ensuing progress in the field resulted in a paradigm shift in the science of crystallography. A new definition of crystal emerged, one that is beautiful and humble and open to further discoveries. A humble scientist is a good scientist.
Science is the ultimate tool to reveal the laws of nature and the one word written on its banner is TRUTH. The laws of nature are neither good nor bad. It is the way in which we apply them to our world that makes the difference.
It is therefore our duty as scientists to promote education, rational thinking and tolerance. We should also encourage our educated youth to become technological entrepreneurs. Those countries that nurture this knowhow will survive future financial and social crises. Let us advance science to create a better world for all.
I would like to thank the scientists who nominated me, the Nobel Committee, the Royal Swedish Academy of Sciences and the Nobel Foundation for bestowing on me this unparalleled honor.