OpenFrontiers
← Back to the index

Many-body localization

For a specified ensemble of interacting disordered spin chains, establish or exclude thermodynamic many-body localization with a stated energy window, probability bound and quasilocal-integral-of-motion criterion. Determine stability under a bounded local pert

Source-reported statusAs of 2026-09-04Source & evidence ↓

Problem statement

For a specified ensemble of interacting disordered spin chains, establish or exclude thermodynamic many-body localization with a stated energy window, probability bound and quasilocal-integral-of-motion criterion. Determine stability under a bounded local perturbation class; treat higher-dimensional avalanche instability separately.

Lean 4

Not yet attached

No Lean statement or proof is attached yet. Have a formalization? Share its source to add it to this problem.

Background

Many-body localization (MBL) is the conjectured survival of Anderson localization once interactions are switched on: an isolated, strongly disordered interacting system fails to thermalize, retains memory of initial conditions, and exhibits an emergent set of quasilocal integrals of motion (l-bits) with only logarithmic entanglement growth.

What is known: The strongest rigorous result is Imbrie's proof of MBL for a specific disordered 1D quantum spin chain, conditional on a physically reasonable but unproven level-statistics (limited level attraction) assumption. Perturbative and numerical studies broadly support an MBL phase in strongly disordered 1D systems.

The status is genuinely contested. De Roeck and Huveneers develop an ETH-based avalanche theory: rare thermal regions may destabilize localization, with particularly severe higher-dimensional predictions. This is not an unconditional theorem excluding every d≥2d\ge2 MBL model. Finite-size drifts make numerical extrapolation difficult. A rigorous result must state its disorder law, interaction strengths, energy window, localization diagnostic and perturbation norm; absence of fast transport at accessible sizes does not itself prove a stable thermodynamic phase. Related: B4, B7, U3.

Progress & source assessment

Source catalogue review: 4 September 2026. Improved indicates partial progress, including qualified preprint claims.

References
  1. [1]Imbrie, 'On many-body localization for quantum spin chains', J. Stat. Phys. 163 (2016) link
  2. [2]De Roeck & Huveneers, 'Stability and instability towards delocalization in MBL systems', PRB 95, 155129 (2017) link
  3. [3]Abanin, Altman, Bloch, Serbyn, 'Many-body localization, thermalization, and entanglement', Rev. Mod. Phys. 91, 021001 (2019) link

Recorded progress

Add yours →

Nothing recorded yet. A pointer to a paper the entry is missing counts.

Machine attempts

0 recorded

Attempts run against the statement below and are recorded in full, including the failures. The point is to stop the next model — and the next person — from re-walking a road that is already known to end. Each attempt costs 25 credits.

No machine attempts recorded.

Sign in to run an attempt. New accounts start with enough credits for ten.

Discussion

0 notes

Notes are for clarifying the statement, flagging a missing reference, or recording why an approach fails. Claimed solutions belong in a submission, where they can be reviewed.

No notes yet.

Sign in to add a note.