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All instances / Hubbard

Hubbard square 8x8, U = 8, n = 0.875

Best values (rules §6)

best variational -0.7532 VMC (transformer BF)
Gu et al. (2026) · the lowest unflagged variational energy, a strict variational bound
best projected -0.7616(1) CP-AFQMC
Levy et al. (2023) · the lowest unflagged projected energy, a projected estimate, which depends on its node or constraint

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 = 8, N↑ = N↓ = 28 on 64 sites.

lattice
square
sites
64
boundary
periodic
Nf
28
U
8
energies
11

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 (9)

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
-0.7532best variational 0 n/a n/a n/a VMC (transformer BF)
peer reviewed
Gu et al. (2026) bytedance/laqx 2026
-0.7469 6.3e-3 2.0e-4 3.50e+0 9.2e-3 VAFQMC
peer reviewed
Levy et al. (2023) 2023
-0.7458 7.4e-3 6.0e-4 3.36e+0 8.9e-3 VMC (JBf-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025
-0.7454 7.8e-3 9.0e-4 3.60e+0 9.5e-3 VMC (HFDS-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025
-0.74220 1.1e-2 3.1e-5 6.62e+0 1.8e-2 VMC (Jastrow + BF)
VarBench reference run
Wu et al. (2024) run script 2024
-0.7422 1.1e-2 3.0e-4 4.47e+0 1.2e-2 VMC (JBf-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025
-0.736 1.7e-2 1.0e-3 6.72e+0 1.8e-2 VMC (HFDS-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025
-0.729 2.4e-2 4.0e-3 8.90e+0 2.4e-2 VMC (HFDS-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025
-0.726 2.7e-2 9.0e-3 1.08e+1 2.9e-2 VMC (JBf-ViT)
peer reviewed
Sharma et al. (2025) uses NetKet 2025

Projected or fixed-node estimates (2)

Variational only within a constraint: fixed-node, constrained-path, GFMC on a trial state. Each depends on its node or constraint, so two of them are not cleanly comparable to each other or to strict bounds.

E/sitedistance to class bestσVar(E)V-score methodsourcecodeyearcomment
-0.7616best projected 0 1.0e-4 n/a n/a CP-AFQMC
peer reviewed
Levy et al. (2023) 2023
-0.74928 1.2e-2 1.6e-5 n/a n/a FN-GFMC (Jastrow + BF)
VarBench reference run
Wu et al. (2024) run script 2024

How these numbers were read

Where each number below was read, and how it was checked.

-0.7616(1), CP-AFQMC

Checked 2026-09-15 · source text of arXiv:2308.08594 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; single reading

Reported as. −0.7616(1)

Table I | 8x8=64 sites P; n=0.875 => Nf=28 per spin; U=8; catalogue best_per_site for this instance is -0.74928125, so this quoted value is notably lower (stronger) than the current catalogue best

-0.7532, VMC (transformer BF)

Checked 2026-10-22 · source text of arXiv:2507.02644 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; single reading

Reported as. −0.7532

Supplementary Table 5, row 8 × 8, t' = 0; dl/gu-si.txt line 187; no error bar | Energy per site in units of t. PBC per the Supplementary Table 5 caption ('Raw data for the energies of Hubbard model under PBC'); U = 8 and hole doping 1/8 per the main text (Fig. 4 caption: 'U = 8 and hole doping δ = 1/8 under PBC'; the t' = -0.2 study: 'Lx × 8 with Lx ranging from 8 to 32, with t' = -0.2 and δ = 1/8'). H has -t' sum_<<ij>>, so t2 = t'. The 16 x 4 and 16 x 16 values at t' = 0 equal the arXiv text's -0.76298 and -0.75630 to the printed digits. No error bar printed. Version read: journal Supplementary Information (41467_2026_74028_MOESM1_ESM.pdf); the arXiv text has no raw-data table.

-0.7469(2), VAFQMC

Checked 2026-09-15 · source text of arXiv:2308.08594 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; single reading

Reported as. −0.7469(2)

Table I | same instance as above | variance reported as 3.5, not stored: convention not verified

-0.7458(6), VMC (JBf-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.7458 (+/- 0.0006), sigma^2/M = 0.0525

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Row "JBf (8x8 Torus)".

-0.7454(9), VMC (HFDS-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.7454 (+/- 0.0009), sigma^2/M = 0.0563

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Row "HFDS (8x8 Torus)".

-0.7422(3), VMC (JBf-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.7422 (+/- 0.0003), sigma^2/M = 0.0698

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Right-hand table, row "JBf-ViT"; same lattice and parameters per the caption.

-0.736(1), VMC (HFDS-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.736 (+/- 0.001), sigma^2/M = 0.105

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Right-hand table, row "HFDS-ViT".

-0.729(4), VMC (HFDS-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.729 (+/- 0.004), sigma^2/M = 0.139

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Right-hand table, row "HFDS Symm-ViT-Ti".

-0.726(9), VMC (JBf-ViT)

Checked 2026-09-14 · arXiv HTML parsed locally, no LLM transcription

Reported as. E_0/M = -0.726 (+/- 0.009), sigma^2/M = 0.168

Read from Table 1 of arXiv:2510.11710 (U/t = 8, n_h = 1/8, energies per site, 131072 samples), parsed from the arXiv HTML. Right-hand table, row "JBf Symm-ViT-Ti".

Coverage

Newest published number here: 2026. Literature last checked 2026-09-15 (table harvest of cached arXiv sources (match_tables.mjs --all), every matched paper read for this instance): 8 papers read, 0 of them with an energy on this page.

This instance as data

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