Hubbard square 8x8, U = 4, n = 0.4375

Hubbard/square_64_P_14_4

No record

—

no variational row (rules §6). Every row is still listed below.

The Hamiltonian

H = −t ∑_⟨ij⟩,σ (c^†_iσc_jσ + h.c.) + U ∑_i n_i↑n_i↓

t = 1, U = 4, N_↑ = N_↓ = 14 on 64 sites.

lattice: square
sites: 64
boundary: periodic
Nf: 14
U: 4
energies: 1

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

Every published energy

Grouped by what the number is. Ranking happens only inside the first group.

Projected or fixed-node estimates (1)

Variational only within a constraint: fixed-node, constrained-path, GFMC on a trial state. Node- or constraint-dependent, so not cleanly comparable to each other or to the group above, and never the record.

E/site	σ	Var(E)	V-score	method	source	year
-1.07180(2)	2.0e-5	n/a	n/a	CP AFQMC with Constraint Release; no strict upper bound property	Shi & Zhang (2013)	2013

Coverage

Newest published number here: 2013. Nothing has been added to this instance since the VarBench snapshot of 2024-10-22.

This instance as data

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