Frozen chaos
the dynamics of glass is what recent work by P Chandra and colleagues at the nec Research Institute, Princeton, us , may shed a new light on. In our understanding of the nature of the states of matter, it is generally accepted that for any substance, rigidity and order always go together. In crystalline solids, applying a force at any one point causes no rearrangement of atoms in the periodic lattice, because the whole lattice responds to the force. This is in sharp contrast to a fluid, where pushing it in one place causes a rearrangement ( Physical Review Letters , Vol 76, No 25).
Glass, however, stands out as an exception to this rule. Here is an amorphous solid with a disorderly arrangement of atoms in it which behaves rigidly