Predictions → Quintom w-Crossing
Prediction
Quintom w-Crossing
The quintom bounce unifies the bounce with dark energy through phantom fields. It predicts the dark energy equation of state w(z) crosses −1 (quintom-B behavior). The DESI DR2 BAO + supernova combination from external groups now reports w-crossing at 2.8–4.2σ, but this is treated theoretically in our program — we have not run a free-w0–wa MCMC ourselves.
Current constraint
P1A's model-discrimination table records no in-house free-w0–wa analysis. P1B is namaster-proof research software, not an MCMC paper. Quintom discussion is theoretical context only; external DESI analyses do not establish a BigBounce result.
Key results
- Quintom bounce achieves bounce↔dark-energy unification that ECH cannot
- Discrimination table positions quintom vs matter bounce vs cuscuton vs ekpyrotic vs inflation
- External DESI DR2 (Adame et al.) shows 2.8–4.2σ w-crossing — independent of our program
- An earlier in-house claim of P(quintom-B) = 98.6% (50.9K samples) was traced to a bookkeeping error in an automated run and retracted — there are zero free-w0–wa samples in any of our chains
Connected work
Papers: Paper 1A — quintom framework + model-discrimination table
Timeline
DESI DR2 (external groups) shows 2.8–4.2σ for w-crossing. Our independent MCMC has not yet been run.
Next steps
- openStand up an actual quintom MCMC: add free w0, wa to the model and run on DESI DR2 BAO + Pantheon+ + DES SN5YR
- openAdd DES Y6 weak lensing once chains exist
- openCompute quintom bounce fNL (fill literature gap)
- openDecide whether quintom belongs as its own paper or as a Paper 1A discrimination-table expansion