Quantum simulation · SU(2) lattice gauge theory

When does a
hadron become measurable?

A reproducible workbench for non-Abelian hadron dynamics — from 120-qubit QASM on IBM hardware to tensor networks and an explicitly validated LSH Hamiltonian.

LSH chainN = 60
LSH latticeA chain of alternating vacuum and occupied sites with incoming and outgoing qubit occupations.SCVvacmesonvacSCVnᵢnₒ
120qubits
x = 100coupling
20Trotter steps

Not one algorithm on three machines, but three complementary lines of evidence: hardware execution, the same compiled circuits on classical MPS simulators, and independent small-system validation of the underlying Hamiltonian.

01 · Architecture

Three routes, one control question

Each route answers a different part of the reproducibility question.

A

Quantum hardware

Fire Opal + IBM

The original unitary QASM receives full Z-basis measurements and separate all-0/all-1 readout calibration.

  • 120 qubits
  • SCV and meson states
  • Raw and corrected counts
→ Δnf, Q, hardware time
B

Circuit level

Aer + ITensor MPS

The same compiled QASM is simulated locally as a matrix-product state.

  • Apples-to-apples circuit check
  • Explicit bond dimension and cutoff
  • Not the full paper TDVP
→ classical sanity baseline
C

Physical validation

LSH dense → MPO → TDVP

Local LSH operators are embedded in Gauss-law-valid sectors and checked against exact evolution.

  • Hermiticity and sector conservation
  • Dense-versus-MPO check
  • Build-up toward N = 60
→ model implementation validation

02 · Physics

Gauge-invariant building blocks

The Loop-String-Hadron representation rewrites the local degrees of freedom as one bosonic loop variable and two binary fermion occupations.

|n, ni, no
n
bosonic flux, truncated numerically
ni, no
incoming and outgoing fermion occupations
Q
conserved total charge; target value Q = 60

Dimensionless Hamiltonian

H = HE + μHM + xHI

Abelian Gauss Law on every link

NL(r) = NR(r + 1)
NL = n + no(1 − ni)NR = n + ni(1 − no)

From Z-basis counts

n = ½(1 − ⟨Z⟩)

The local signal is Δnf = nfmeson − nfSCV.

03 · Results

Step 5 in perspective

The timings below use different scopes. That distinction is part of the result.

Fire Opal main circuits

0.987shardware-only · 512 shots · ibm_fez
Aer MPS · compiled QASM34.281 s34.7×
ITensor MPS · compiled QASM174.611 s176.9×
Paper · Pauli Propagation CPU477.447 s483.7×
Paper · Pauli Propagation GPU547.581 s554.7×
Paper · ITensor/TDVP TN584.092 s591.7×

Fire Opal smoke runs

Signal across Trotter depth

all actions succeeded
StepDepthRaw ΔnfReadout-correctedHardware time
0566−0.75195−0.764250.987 s
10125+0.32422+0.334841.581 s
15177−0.06836−0.054412.175 s
20237−0.38672−0.390002.769 s

Hardware time = estimated circuit duration × shots. Queueing, compilation, API wait and local decoding are excluded.

Dense ↔ MPO/TDVP · N = 4

1.20 × 10−8RMSE in local Q profile

Energy difference

1.11 × 10−11exact versus TDVP evolution

Norm difference

2.50 × 10−13small-system smoke test

04 · Claim boundaries

What this repository does — and does not yet — demonstrate

A fast execution time is compelling only when task, accuracy and time definition are matched.

Supported

Reproducible technical route

  • Fire Opal actions and metadata are captured locally.
  • The same QASM is tested classically at MPS level.
  • The small LSH-MPO route agrees with exact evolution.
  • Global charge Q acts as a physical diagnostic.
Still open

Full quantum-advantage claim

  • Local Δnf and tracker nf(t) do not yet share a matched normalization.
  • The N = 60 LSH-TDVP reproduction has not been run locally.
  • Hardware-only time is not end-to-end wall-clock time.
  • The 512-shot runs are smoke tests, not a precision campaign.

05 · Start here

Read the repository in this order

  1. 01
    README.md

    Purpose, directories and current claim boundary.

  2. 02
    HADRON_FIRE_OPAL.md

    Hardware route, runtimes and benchmark results.

  3. 03
    hadron_observable_analyzer.py

    From Z-basis counts to Q and Δnf.

  4. 04
    lsh_mpo_build_notes.md

    The route from the local LSH basis to MPO/TDVP.

  5. 05
    hadron_quantum_win_boundary.md

    The compact, current timing interpretation.

Open, inspectable, bounded

From an impressive number
to a testable claim.