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All instances / t-J

t-J square 8x8, open, J = 0.333333, 1 hole

Best values (rules §6)

best variational -0.380099 DMRG
10.1103/c75n-7j8f, · 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 P(c†iσcjσ + h.c.)P + J ∑⟨ij⟩ (Si·Sj − ninj/4)

t-J model: P projects out doubly occupied sites, S = σ/2. t = 1, J = 0.333333; the exchange term includes −ninj/4. N↑ = 32, N↓ = 31 on 64 sites (1 hole). Cluster: 8 x 8 square lattice, open boundaries (arXiv:2602.21206: 'N_x x N_y under the OBC').

lattice
square
sites
64
boundary
open
t
1
J
0.3333333333333333
N_up
32
N_dn
31
nn_term
true
energies
4

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 (4)

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
-0.380099best variational 0 n/a n/a n/a DMRG
peer reviewed
10.1103/c75n-7j8f, 2026
-0.372224 7.9e-3 n/a n/a n/a VMC (phase string)
peer reviewed
10.1103/c75n-7j8f, 2026
-0.3719792 8.1e-3 n/a n/a n/a VMC (Bloch wave)
peer reviewed
10.1103/c75n-7j8f, 2026
-0.3540625 2.6e-2 n/a n/a n/a VMC (Bloch wave)
peer reviewed
10.1103/c75n-7j8f, 2026

How these numbers were read

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

-0.380099, DMRG

Checked 2026-10-22 · source text of arXiv:2602.21206 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; first reading and an adversarial second reading (2026-10-22)

Reported as. −72.979

text: E_tot(DMRG) of the 8 x 8 lattice, OBC, one hole, t = 3, J = 1 (line 201); version read: arXiv text (sources/2602.21206.txt); the journal version was not reached from this session (the publisher returned 403), to be read on the verification pass (RULES.md 8) | Eqs. (4)-(5): H = P(H_t + H_J)P, H_t = -t sum (c+c + H.c.), H_J = J sum (S_i.S_j - n_i n_j / 4), J = 1 the energy unit and t = 3 (lines 185-186): the instance's J/t = 1/3 and a factor 3 (scale). Total energies E_tot of the 8 x 8 OBC lattice with one hole.

-0.372224, VMC (phase string)

Checked 2026-10-22 · source text of arXiv:2602.21206 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; first reading and an adversarial second reading (2026-10-22)

Reported as. −71.467

text: E_tot(VMC) of the 8 x 8 lattice, OBC, one hole, t = 3, J = 1 (line 200); version read: arXiv text (sources/2602.21206.txt); the journal version was not reached from this session (the publisher returned 403), to be read on the verification pass (RULES.md 8) | Eqs. (4)-(5): H = P(H_t + H_J)P, H_t = -t sum (c+c + H.c.), H_J = J sum (S_i.S_j - n_i n_j / 4), J = 1 the energy unit and t = 3 (lines 185-186): the instance's J/t = 1/3 and a factor 3 (scale). Total energies E_tot of the 8 x 8 OBC lattice with one hole.

-0.3719792, VMC (Bloch wave)

Checked 2026-10-22 · source text of arXiv:2602.21206 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; first reading and an adversarial second reading (2026-10-22)

Reported as. -71.42

Table III, E_tot, row |Ψ_Lanczos⟩_1h (line 1149); version read: arXiv text (sources/2602.21206.txt); the journal version was not reached from this session (the publisher returned 403), to be read on the verification pass (RULES.md 8) | Eqs. (4)-(5): H = P(H_t + H_J)P, H_t = -t sum (c+c + H.c.), H_J = J sum (S_i.S_j - n_i n_j / 4), J = 1 the energy unit and t = 3 (lines 185-186): the instance's J/t = 1/3 and a factor 3 (scale). Total energies E_tot of the 8 x 8 OBC lattice with one hole.

-0.3540625, VMC (Bloch wave)

Checked 2026-10-22 · source text of arXiv:2602.21206 read locally (arXiv HTML or pypdf layout text); value copied from the harvested cell and the text, no LLM transcription of numbers; first reading and an adversarial second reading (2026-10-22)

Reported as. -67.98

Table III, E_tot, row |Ψ_Bloch⟩_1h (line 1148); version read: arXiv text (sources/2602.21206.txt); the journal version was not reached from this session (the publisher returned 403), to be read on the verification pass (RULES.md 8) | Eqs. (4)-(5): H = P(H_t + H_J)P, H_t = -t sum (c+c + H.c.), H_J = J sum (S_i.S_j - n_i n_j / 4), J = 1 the energy unit and t = 3 (lines 185-186): the instance's J/t = 1/3 and a factor 3 (scale). Total energies E_tot of the 8 x 8 OBC lattice with one hole.

Coverage

Newest published number here: 2026.

This instance as data

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