A look back into history tells us that crystallography was developed without a definition of a crystal, or more precise: the definition has grown with the knowledge about an only vaguely described object. This is painful for mathematicians but not for physicists. Physicists can show the material they deal with, it exists as soon as they have shown, named and described it, mathematicians have to define it: it does not exist as long as it is not defined. ...
Print ISSN: 0044-2968
Volume: 222, 06/2007
Pages: 318 - 319