Roadmap
This page tracks the next methodological and documentation milestones for the ξ Dark Energy project.
Why this page is included
The sidebar references a Community Roadmap page. Including this file prevents a missing-doc route and gives readers a clear path from the v0.1 limitations toward the planned v0.2 robustness work.
Current status
The current version should be treated as an exploratory v0.1 analysis. It is useful as a reproducible cosmology pipeline and a portfolio-level demonstration of MCMC inference, but it should not be presented as a confirmed cosmological result.
| Area | Status |
|---|---|
| Pantheon+SH0ES likelihood | Implemented |
| DESI DR2 BAO likelihood | Implemented |
| ΛCDM baseline | Implemented |
| CPL comparison | Implemented |
| ξ oscillatory model | Exploratory |
| MCMC diagnostics | Implemented, but convergence needs careful reporting |
| Prior sensitivity | Planned |
| Public release polish | Planned |
v0.2 priorities
1. Prior sensitivity
- Verify all prior bounds directly from the sampler configuration.
- Add a symmetric prior test for
epsilon. - Compare linear-period and log-period prior choices.
- Report whether posterior mass is boundary-limited.
- Update the Prior Specification page after final verification.
2. Time variable and oscillation definition
- Audit the definition of the time variable used in the ξ term.
- Verify whether the implementation uses lookback time, cosmic time, scale factor, or redshift.
- Confirm that the oscillation period
Tis interpreted consistently. - Add a diagram or equation block to the model-definition page.
3. Convergence and robustness
- Run longer chains if autocorrelation times remain large.
- Report acceptance fraction.
- Report integrated autocorrelation time.
- Show trace plots for all parameters.
- Verify that the posterior is stable across walker initialization.
- Compare medians across independent chains.
4. Model comparison caution
- Clarify what AIC/BIC can and cannot say.
- Avoid interpreting small score differences as decisive evidence.
- Add posterior predictive plots for all models.
- Compare residuals against redshift.
Documentation priorities
| Priority | Page | Task |
|---|---|---|
| P1 | Known Limitations | Make v0.1 caveats impossible to miss |
| P1 | Prior Specification | Replace placeholder bounds with exact values |
| P1 | Convergence | Add final trace/autocorrelation diagnostics |
| P1 | Parameter Constraints | Add final table with caveat language |
| P2 | Model Comparison | Add AIC/BIC interpretation guardrails |
| P2 | Outputs | Document generated files and figures |
| P3 | Citing | Add DOI / release metadata |
Release readiness checklist
Before tagging a stable public release:
- All model equations are documented.
- All priors are documented with exact bounds.
- All likelihood terms are documented.
- Data versions are explicitly stated.
- MCMC configuration is reproducible.
- Convergence diagnostics are published.
- Known limitations are linked from every result page.
- Posterior samples are archived or reproducible.
- Claims are added to the Scientific Claims Register.
- Citation metadata is updated.
Recommended framing
The best framing for this project is:
A reproducible exploratory cosmology pipeline testing whether an oscillatory phenomenological extension can be constrained with current SN Ia and BAO data, with explicit emphasis on priors, convergence, and model-comparison caveats.
This framing is strong because it is ambitious, honest, and methodologically mature.
Related pages
| Page | Role |
|---|---|
| Models | Defines ΛCDM, CPL, and ξ |
| Likelihood | Data likelihood |
| Prior Specification | Prior contract |
| Convergence | MCMC diagnostics |
| Known Limitations | v0.1 caveats |
| Citing | Citation and release metadata |