Physical symmetry of quasicrystals
نویسنده
چکیده
The possibility of a physical rotational symmetry for a quasicrystal is discussed and the minimal tensorial rank which is necessary to detect such a symmetry is shown to be simply related to the order of a symmetry rotation. For icosahedral symmetry, in particular, the minimal rank is 5 which means that "ordinary" linear (i.e. first order) behaviour (in the termal, electromagnetic, déformation quantities) is expected to be isotropic as in a glass. Anisotropy, as in a crystal, is accordingly possible only in the nonlinear domain. Tome 48 N° 6 JUIN 1987 J. Physique 48 (1987) 893-895 J U I N 1987,
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