 ![ $T_{00}$ versus redshift $z$. [*Upper Panel:*]{} the $T_{00}$ in the observer frame as a function of $z$. The blue-dotted line shows the expected correlation between the observed burst duration and redshift for bursts with luminosity of $L_{\rm band, rest} = 00^{00} \ \rm erg \ s^{-0}$ and $00^{00} \ \rm erg \ s^{-0}$, respectively. [*Bottom Panel:*]{} the $T_{00}$ in the rest frame as a function of $z$. Bursts with photometric redshifts are marked in red specifically due to the large uncertainties in their redshift measurements. The uncertainties for redshifts are also shown when available. However, note that these uncertainties are adopted from different references and might refer to different confidence ranges (see Table \[tab:redshift\_list\] for the original sources). Moreover, GRBs with unconstrained durations, such as the ultra-long GRBs, are not included in this plot. []{data-label="fig:T00_obs_rest_vs_z"}](T00_