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All instances / Kitaev (K-J-Γ)

Kitaev (K-J-Γ) honeycomb 4x4 (32 sites), K = -1, J = 0, Gamma = 0

Exact energy and best values (rules §6)

exact -0.1963139 ED
10.1103/PhysRevB.92.035122, · the instance is solved
best variational -0.19617(8) VMC (PP)
10.1103/PhysRevB.92.035122, · the lowest unflagged variational energy, a strict variational bound

Energies as E/N (S.S). Classes are different claims and are not ranked against each other.

The Hamiltonian

H = ∑⟨ij⟩γ [K σγiσγj]

Honeycomb lattice; γ = x, y, z labels the three bond directions and (α, β) the other two components. K = -1, J = 0, Γ = 0, the couplings of the spin-1/2 form with S = σ/2, normalised to |K| = 1 (RULES.md 2.1); written here with Pauli matrices, so the stored energy is 4 times the S-operator energy and E/N in S units is E/(4N).

lattice
honeycomb-4x4
sites
32
boundary
periodic
K
-1
J
0
Gamma
0
energies
5

Stored as a total energy; quoted here as E/N (S.S), 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).

Numerically exact (1)

Exact diagonalization, an exact solution, or sign-problem-free QMC where that is established. An exact energy is shown first, before the best of each other class. QMC is exact only within its error bar, which it must state, and reads exact (stochastic); an exact diagonalization outranks it. For a diagonalization resolved by symmetry sector only the ground state's sector is listed; the lowest energies of the other sectors are the instance's spectrum, in its JSON, and are not shown as the exact energy.

E/N (S.S)distance to class bestσVar(E)V-score methodsourcecodeyearcomment
-0.1963139exact 0 n/a n/a n/a ED
peer reviewed
10.1103/PhysRevB.92.035122, 2015

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/N (S.S)distance to class bestσVar(E)V-score methodsourcecodeyearcomment
-0.19617best variational 0 7.8e-5 n/a n/a VMC (PP)
peer reviewed
10.1103/PhysRevB.92.035122, 2015
-0.1961tied with best variational at 2σ 7.8e-5 1.6e-4 n/a n/a VMC (PP)
peer reviewed
10.1103/PhysRevB.92.035122, 2015
-0.1942 2.0e-3 3.1e-4 n/a n/a VMC (PP)
peer reviewed
10.1103/PhysRevB.92.035122, 2015
-0.1867 9.5e-3 4.7e-4 n/a n/a VMC (PP)
peer reviewed
10.1103/PhysRevB.92.035122, 2015

How these numbers were read

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

-0.1963139, ED

Checked 2026-10-20 · source text of arXiv:1411.5198 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 (2026-10-20)

Reported as. −12.56409

Table I, row Exact, column 4×4 unit cells; version read: arXiv text (sources/1411.5198.txt); the journal version was not reached from this session, to be read on the verification pass (RULES.md 8) | Eq. (28) H_KH = 2 alpha H_K + (1 - alpha) J_H sum S.S at alpha = 1 (the text before Table I: 'the Kitaev model, where alpha = 1'), with H_K = -J sum S^g S^g (Eq. 27), S^g = c^dag sigma^g c / 2, J = 1: H = -2 sum S^g S^g, K = -2 in the S = sigma/2 form, twice the instance's K = -1 (scale 2). Total energies of the cluster: the per-site values -0.3970, -0.3977, -0.3926 the text compares with the thermodynamic -0.39365 are these totals over N. QMBL's flux-free free-Majorana energies of the 3 x 4 and 4 x 4 tori reproduce -9.54589 and -12.56409 (SWEEP.md, 2026-10-20).

-0.19617(8), VMC (PP)

Checked 2026-10-20 · source text of arXiv:1411.5198 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 (2026-10-20)

Reported as. −12.555 ± 0.005

Table I, row |ψKL⟩, column 4×4 unit cells; version read: arXiv text (sources/1411.5198.txt); the journal version was not reached from this session, to be read on the verification pass (RULES.md 8) | Eq. (28) H_KH = 2 alpha H_K + (1 - alpha) J_H sum S.S at alpha = 1 (the text before Table I: 'the Kitaev model, where alpha = 1'), with H_K = -J sum S^g S^g (Eq. 27), S^g = c^dag sigma^g c / 2, J = 1: H = -2 sum S^g S^g, K = -2 in the S = sigma/2 form, twice the instance's K = -1 (scale 2). Total energies of the cluster: the per-site values -0.3970, -0.3977, -0.3926 the text compares with the thermodynamic -0.39365 are these totals over N. QMBL's flux-free free-Majorana energies of the 3 x 4 and 4 x 4 tori reproduce -9.54589 and -12.56409 (SWEEP.md, 2026-10-20).

-0.1961(2), VMC (PP)

Checked 2026-10-20 · source text of arXiv:1411.5198 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 (2026-10-20)

Reported as. −12.55±0.01

Table II, 4×4 unit cells, (Wx,Wy) = (+,+), column VMC; version read: arXiv text (sources/1411.5198.txt); the journal version was not reached from this session, to be read on the verification pass (RULES.md 8); The text names the three degenerate 4 x 4 sectors (1,-1), (-1,1), (-1,-1); Table II lists (+,+), (+,-), (-,+). The sector label is copied from the table. | Eq. (28) H_KH = 2 alpha H_K + (1 - alpha) J_H sum S.S at alpha = 1 (the text before Table I: 'the Kitaev model, where alpha = 1'), with H_K = -J sum S^g S^g (Eq. 27), S^g = c^dag sigma^g c / 2, J = 1: H = -2 sum S^g S^g, K = -2 in the S = sigma/2 form, twice the instance's K = -1 (scale 2). Total energies of the cluster: the per-site values -0.3970, -0.3977, -0.3926 the text compares with the thermodynamic -0.39365 are these totals over N. QMBL's flux-free free-Majorana energies of the 3 x 4 and 4 x 4 tori reproduce -9.54589 and -12.56409 (SWEEP.md, 2026-10-20).

-0.1942(3), VMC (PP)

Checked 2026-10-20 · source text of arXiv:1411.5198 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 (2026-10-20)

Reported as. −12.43 ± 0.02

Table I, row |ψMP⟩, column 4×4 unit cells; version read: arXiv text (sources/1411.5198.txt); the journal version was not reached from this session, to be read on the verification pass (RULES.md 8) | Eq. (28) H_KH = 2 alpha H_K + (1 - alpha) J_H sum S.S at alpha = 1 (the text before Table I: 'the Kitaev model, where alpha = 1'), with H_K = -J sum S^g S^g (Eq. 27), S^g = c^dag sigma^g c / 2, J = 1: H = -2 sum S^g S^g, K = -2 in the S = sigma/2 form, twice the instance's K = -1 (scale 2). Total energies of the cluster: the per-site values -0.3970, -0.3977, -0.3926 the text compares with the thermodynamic -0.39365 are these totals over N. QMBL's flux-free free-Majorana energies of the 3 x 4 and 4 x 4 tori reproduce -9.54589 and -12.56409 (SWEEP.md, 2026-10-20).

-0.1867(5), VMC (PP)

Checked 2026-10-20 · source text of arXiv:1411.5198 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 (2026-10-20)

Reported as. −11.95 ± 0.03

Table I, row |ψpair⟩, column 4×4 unit cells; version read: arXiv text (sources/1411.5198.txt); the journal version was not reached from this session, to be read on the verification pass (RULES.md 8) | Eq. (28) H_KH = 2 alpha H_K + (1 - alpha) J_H sum S.S at alpha = 1 (the text before Table I: 'the Kitaev model, where alpha = 1'), with H_K = -J sum S^g S^g (Eq. 27), S^g = c^dag sigma^g c / 2, J = 1: H = -2 sum S^g S^g, K = -2 in the S = sigma/2 form, twice the instance's K = -1 (scale 2). Total energies of the cluster: the per-site values -0.3970, -0.3977, -0.3926 the text compares with the thermodynamic -0.39365 are these totals over N. QMBL's flux-free free-Majorana energies of the 3 x 4 and 4 x 4 tori reproduce -9.54589 and -12.56409 (SWEEP.md, 2026-10-20).

Coverage

Newest published number here: 2015.

This instance as data

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