2 problems

Consider an infinite solid phase, and let $\Gamma^{\mathrm{c.m.}}_{\infty}$ be the probability of infinite total momentum. For a crystal, let ${\mathbb L}^*$ be the reciprocal latt…

For a quantum crystal in any dimension, let $\gamma$ denote its mass gap, let $J$ be the coupling parameter, and let $q$ be the deformation parameter. Mass-gap conjecture. The mass…