TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.18.3.107
TI  - Nonlocality of deep thermalization
PY  - 2025/03/21
UR  - https://scipost.org/SciPostPhys.18.3.107
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 18
IS  - 3
SP  - 107
A1  - Shrotriya, Harshank
AU  - Ho, Wen Wei
AB  - We study the role of global system topology in governing deep thermalization, the relaxation of a local subsystem towards a maximally-entropic, uniform distribution of post-measurement states, upon observing the complementary subsystem in a local basis. Concretely, we focus on a class of (1+1)d systems exhibiting 'maximally-chaotic' dynamics, and consider how the rate of the formation of such a universal wavefunction distribution depends on boundary conditions of the system. We find that deep thermalization is achieved exponentially quickly in the presence of either periodic or open boundary conditions; however, the rate at which this occurs is twice as fast for the former than for the latter. These results are attained analytically using the calculus of integration over unitary groups, and supported by extensive numerical simulations. Our findings highlight the nonlocal nature of deep thermalization, and clearly illustrates that the physics underlying this phenomenon goes beyond that of standard quantum thermalization, which only depends on the net build-up of entanglement between a subsystem and its complement.
ER  -

@Article{10.21468/SciPostPhys.18.3.107,
	title={{Nonlocality of deep thermalization}},
	author={Harshank Shrotriya and Wen Wei Ho},
	journal={SciPost Phys.},
	volume={18},
	pages={107},
	year={2025},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.18.3.107},
	url={https://scipost.org/10.21468/SciPostPhys.18.3.107},
}