5 problems

Consider the mirrors model on the lattice $\mathbb{Z}^d$, with a mirror placed independently at each site with probability $p$, and let a particle move along lattice edges, choosin…

Haldane's conjecture. These two relations should hold for a large universality class, including the solvable XXZ quantum spin chain and its non-integrable perturbations. The relati…

At positive temperature, the Drude weight is the transport coefficient associated with the ballistic component of conductivity. A quantum spin chain is integrable when it possesses…

Consider the spin-$\frac{1}{2}$ XXZ chain with anisotropy parameter $\Delta$, and let $L$ denote the Onsager coefficient governing the diffusive contribution to transport. The isot…

Let $\eta$ be the shear viscosity, $s$ the entropy density, $\hbar$ the reduced Planck constant, and $k_B$ Boltzmann's constant. Kovtun–Son–Starinets conjecture. The ratio of the s…