qgrav¶
Software-first R&D platform for atom-interferometric gravimetry.
qgrav simulates light-pulse atom-interferometer gravimeters from first principles — the gravity phase emerges from a ballistic atom trajectory under a chirped Raman laser, with finite-duration pulses integrated sub-pulse so the finite-τ physics converges to the Bertoldi 2019 closed form. It models realistic (and emergent Monte-Carlo) noise and systematics, runs multi-drop measurement cycles, ingests real precision-gravity data through a complete tide → pressure → polar-motion → ocean-loading residual chain, and validates itself against five published instruments.
Install¶
Run your first pipeline with qgrav run --config configs/example.yaml, or launch
the desktop GUI with qgrav gui. The Complete guide covers
everything else.
Start here¶
- New to the project? Read the Complete guide.
- Want the physics? See the v1.0 physics upgrade and the physics review packet.
- Designing / extending? See the architecture and the roadmap.
- Reproducibility & honesty: every result carries a study-scope label; see scientific hardening and the AI usage disclosure.
Validation at a glance¶
- Primary regression: Freier 2016 (GAIN), 96 nm/s²/√Hz.
- Secondary: Hu 2013, Ménoret 2018, Xu 2022, Wu 2019.
- Independent cross-check: QuTiP reproduces the Raman dynamics to ~1.6×10⁻⁶.
- Emergent floors: the finite-τ phase converges to the Bertoldi 2019 closed form (≤2×10⁻³ relative), and the multi-drop quantum-projection-noise floor matches σ_g = 1/(√N_det·k_eff·T²) to ~0.2 %.
- Emergent gravity gradient: the simulated Mach-Zehnder gradient phase reproduces the Peters/Chung/Chu (7/12)·γ·g·T⁴ closed form to ~0.1 %.
- Transfer function proven end-to-end: the time-domain vibration mode's realized phase noise matches the integrated Cheinet budget on the same PSD.
- Real data: IGETS superconducting-gravimeter ingest for the analysis chain.
See the repository README.md and CHANGELOG.md for installation and the full
version history.