{
  "model": "Hubbard",
  "lattice": "square",
  "n_sites": 256,
  "boundary": "P",
  "params": {
    "Nf": 112,
    "U": 8
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  "instance_id": "Hubbard/square_256_P_112_8",
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      "reference": "[code](https://github.com/varbench/methods/blob/main/scripts/Hubbard/square_256_P_112_8/VMC-stripes/vmc_hubbard.sh)",
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": null
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": "ACE Table 1 row 'Transformer [13]' = arXiv:2507.02644"
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      "einf": 392,
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": null
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      "einf": 392,
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      "reference": "Gu et al., arXiv:2604.25775 (2026-04-28)",
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        "checked_on": "2026-09-10",
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": "ACE Table 1 row 'Tensor-Backflow+Lanczos [21]'"
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    },
    {
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": null
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      "method": "HFPS + symmetry projection",
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      "bound_type_reason": "assigned from the source text during verification",
      "reference": "Gu et al., arXiv:2604.25775 (2026-04-28)",
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        "reported_as": "-0.7515 (+/- 0.0001) per site",
        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": "ACE Table 1 row 'HFPS+sym [31]'"
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        "checked_on": "2026-09-10",
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        "note": "Read directly from the Table 1 HTML of arXiv:2604.25775, column t'=0 PBC (16x16, U=8, delta=1/8). ACE Table 1 energies are WITHOUT symmetry projection (Sec. III.C.2), so they are not the ansatz floor.",
        "secondary_of": "ACE Table 1 row 'Tensor-Backflow [21]'"
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  ],
  "url": "https://qmbl.org/i/Hubbard/square_256_P_112_8/",
  "per_site_divisor": 256,
  "per_site_label": "E/site",
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}