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Hubbard square 16x16, U = 6, n ≈ 0.8906

Best values (rules §6)

best variational -0.84058(2) VAFQMC
Wu et al. (2024) · the lowest unflagged variational energy, a strict variational bound

Energies as E/site. Classes are different claims and are not ranked against each other.

The Hamiltonian

H = −t ∑⟨ij⟩,σ (c†iσcjσ + h.c.) + U ∑i ni↑ni↓

t = 1, U = 6, N↑ = N↓ = 114 on 256 sites.

lattice
square
sites
256
boundary
periodic
Nf
114
U
6
energies
2

Stored as a total energy; quoted here as E/site, which is what the papers report (how the conversion works).

Every published energy

Grouped by what the number is. The exact energy comes first where there is one; in every other group the lowest unflagged energy is its best value, and each row's distance is to that best (rules §6).

Strict variational upper bounds (2)

Energies that a variational state reached (VMC, DMRG and MPS at finite bond dimension, PEPS, NQS, VQE). Each is an upper bound on the ground-state energy.

E/sitedistance to class bestσVar(E)V-score methodsourcecodeyearcomment
-0.84058best variational 0 2.2e-5 8.40e-1 7.1e-4 VAFQMC Wu et al. (2024) 2024
-0.83072 9.9e-3 1.6e-5 1.18e+1 1.0e-2 VMC (Jastrow + BF)
VarBench reference run
Wu et al. (2024) run script 2024

Coverage

Newest published number here: 2024. Literature last checked 2026-09-15 (citation screen of Sorella 2023 (PRB 107, 115133), VAFQMC doping scan: citing works from OpenAlex and Semantic Scholar (scripts/cited_by.mjs)): 8 papers read, 0 of them with an energy on this page.

This instance as data

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