Recent content by fyw

Dear all, In Marder's Condensed matter physics, it uses matrix operations to explain how to justify two different lattice systems as listed in attachment. However, I cannot understand why the two groups are equivalent if there exists a single matrix S satisfying S-1RS-1+S-1a=R'+a'...

Dear Quack, Thank you for your answer. I've got it. Additionally, can you explain the time symmetry broken induced magnetism and gauge symmetry broken induced superconductor or superliquid?

1. P. Marder ever said that there is no special symmetry results in two dimensional oblique lattice. But it still possesses inversion symmetry. r → -r How to understand r → -r? 2. Many book ever states that space symmetry broken by atomic displacement can bring ferroelectricity. But why...