Round 1
One saved weekly assessment of Pure iron favours bcc over hcp at 330 GPa and 6000 K., kept as it was published. It is an estimate from three models reading the evidence, not proof the hypothesis holds, and it did not set any price.
- Published
- Oct 19, 2026 07:02 PM EDT
- Estimate
- 13%
- Range the models covered
- 4–25%
- Confident binary
- No unanimous verdict this round.
- Methodology
- panel-v9
- Round hash
72a09334ba7245111444615f98984039541a463f55ecb68ae9017deecbf974b2
The hash commits to this round's recorded bytes. It does not prove the wording is sound or that the science is right.
openai/gpt-6.1-sol
I interpret this as the constrained-solid free-energy difference, not stability against melting. Retrieved calculations favor hcp, but the exact-state structure search instead loses the bcc basin, which explicitly cannot establish NO. I found no independently implemented pair reporting qualifying 95% intervals that include electronic-structure, finite-size and sampling errors; the negative sign therefore appears disfavored but remains unresolved.
What would change this view: Independent exact-state calculations retaining both crystalline basins and yielding negative 95% intervals after quantified electronic-structure and sampling errors would substantially raise my estimate.
anthropic/claude-sonnet-5.5
The best direct ab initio thermodynamic-integration work I found, on melting of bcc and hcp Fe at inner-core conditions (GRL 2022), gives bcc about 10–13 meV/atom above hcp. That is the opposite sign to the hypothesis. Belonoshko-type MD claims favour bcc but are model-dependent. The criterion needs wholly-negative intervals from independent calculations, and that is not met. Because the contrary result needs consistent calculations with intervals wholly ≥0, which is also not established, I treat the comparison as NO-leaning.
What would change this view: Multiple independent, converged ab initio anharmonic free-energy calculations with 95% intervals wholly negative for bcc minus hcp at 330 GPa and 6000 K would move me toward YES.
x-ai/grok-4.7
Recent ab initio work at 330 GPa finds hcp lower in free energy than bcc, and one study has bcc leave its basin at 6000 K, so the claimed inequality is poorly supported. Eligible 95% intervals that include finite-size, sampling and electronic-structure error and agree across independent implementations are not published, and bcc free energies still disagree, so neither terminal YES nor NO is met.
What would change this view: Two independent peer-reviewed free-energy calculations at 330 GPa and 6000 K with 95% intervals for G_bcc−G_hcp wholly below zero, bcc stable in-basin.
Round 1: score 0.13
OpenAI estimated 0.25. I interpret this as the constrained-solid free-energy difference, not stability against melting. Retrieved calculations favor hcp, but the exact-state structure search instead loses the bcc basin, which explicitly… Anthropic estimated 0.04. The best direct ab initio thermodynamic-integration work I found, on melting of bcc and hcp Fe at inner-core conditions (GRL 2022), gives bcc about 10–13 meV/atom above hcp. That is the opposite sign to the hypothesis.… xAI estimated 0.10. Recent ab initio work at 330 GPa finds hcp lower in free energy than bcc, and one study has bcc leave its basin at 6000 K, so the claimed inequality is poorly supported. Eligible 95% intervals that include finite-size… The panel disagreed by 0.21, so read this average as soft. The three models did not return a unanimous confident binary, so the market is not decided.
No audit bundle is recorded for this round. A bundle from another round is not substituted for it.