Mermin-Wagner
(1968)
* 2D
systems with a continuous symmetry cannot have a broken symmetry at
T>0
*No long range order
*No Wigner crystal in 2D !
Kosterlitz-Thouless
(1972)
* 2D
systems can have “quasi-long range order” for 0<T<TKT
* The
quasi-ordered state has SHEAR rigidity
* Power
law “Bragg peaks”
* Wigner
crystal?
*