Exponentially slow thermalization in 1D fragmented dynamics

Understand

We investigate the thermalization dynamics of 1D systems with local constraints coupled to an infinite temperature bath at one boundary.

• The coupling to the bath eventually erases the effects of the constraints, causing the system to tend towards a maximally mixed state at long times.
• We show that for a large class of local constraints, the time at which thermalization occurs can be extremely long.
• In particular, we present evidence for the following conjecture: when the constrained dynamics displays strong Hilbert space fragmentation, the thermalization time diverges exponentially with system size.