Universal entropy bound and discrete space-time

Starting from the universal entropy bounds suggested by Bekenstein and Susskind and applying them to the black-body radiation situation, we get a cut-off of space $\mathrm{\Delta }x\ge \chi l_{\mathrm{P}}$ with $\chi \ge 0.1$. We go further to get a cut-off of time $\mathrm{\Delta }t\ge \chi l_{\mathrm{P}}\mathrm{/}c$, thus, the discrete space-time structure is obtained. With the discrete space-time, we can explain the uncertainty principle. Based on the hypothesis of information theory and the entropy of black holes, we get the precise value of the parameter $\chi$ and demonstrate the reason why the entropy bounds hold.