Three-dimensional Ising correlation exponent bounds

Consider the critical three-dimensional Ising model, with spin variables $\mathit{\sigma_x}$ and critical Gibbs measure $\mathit{\mu_{\beta_c}}$. Three-dimensional Ising exponent conjecture. There exist $\mathit{\varepsilon}>0$ and $c_0,c_1\in(0,\infty)$ such that for all $x,y\in\mathbb{Z}^3$,

$$\frac{c_0}{\|x-y\|^{2-\varepsilon}}\le \mu_{\beta_c}[\sigma_x\sigma_y]\le \frac{c_1}{\|x-y\|^{1+\varepsilon}}.$$

The source describes this improvement over the best known three-dimensional bounds as an open problem of significant value.