A materials scientist argues: "Quartz must be ferroelectric
PHYSICS · Subjective · Fermi University Physics · Mathematical Methods for Physics · Condensed Matter, Materials & Soft Matter · Dielectric and optical properties of solids
Solid State Physics, Ch Dielectric response, local fields and ferroelectricity
Problem
A materials scientist argues: "Quartz must be ferroelectric, since it is well known to be piezoelectric, and any piezoelectric crystal is ferroelectric by definition. Also, the Kramers-Kronig relations are a purely mathematical identity between the real and imaginary parts of any complex function of frequency, so they hold for any ε(ω) without needing any physical input." Quartz belongs to point group 32 (D3 in Schoenflies notation). Evaluate both parts of the claim.