English

Full normalization for transfinite stacks

Logic 2024-03-19 v3

Abstract

We describe the extension of normal iteration strategies with appropriate condensation properties to strategies for stacks of normal trees, with full normalization. Given a regular uncountable cardinal Ω\Omega and an (m,Ω+1)(m,\Omega+1)-iteration strategy Σ\Sigma for a premouse MM, such that Σ\Sigma and MM both have appropriate condensation properties, we extend Σ\Sigma to a strategy Σ\Sigma^* for the optimal-(m,Ω,Ω+1)(m,\Omega,\Omega+1)^*-iteration game such that for all λ<Ω\lambda<\Omega and all stacks T=<Tα>α<λ\vec{\mathcal{T}}=\left<\mathcal{T}_\alpha\right>_{\alpha<\lambda} via Σ\Sigma^*, consisting of normal trees Tα\mathcal{T}_\alpha, each of length <Ω{<\Omega}, there is a corresponding normal tree X\mathcal{X} via Σ\Sigma with MT=MXM^{\vec{\mathcal{T}}}_\infty=M^{\mathcal{X}}_\infty. Moreover, if there are no drops in model or degree along the main branches of these trees then the overall iteration maps iT:MMTi^{\vec{\mathcal{T}}}:M\to M^{\vec{\mathcal{T}}}_\infty and iX:MMXi^{\mathcal{X}}:M\to M^{\mathcal{X}}_\infty agree. The construction is the result of a combination of work of John Steel and of the author. We also establish some further useful properties of Σ\Sigma^*, and use the methods to analyze the comparison of multiple iterates via a common such strategy.

Keywords

Cite

@article{arxiv.2102.03359,
  title  = {Full normalization for transfinite stacks},
  author = {Farmer Schlutzenberg},
  journal= {arXiv preprint arXiv:2102.03359},
  year   = {2024}
}

Comments

53 pages. Correct abstract and 1.4 with phrase "optimal"; add 1.2; add hypo to 2.7; in 2.7 Case 1 proof, change < to <= (re $\rho_{r+1}^{R'}$); correct 3.4(ii) (see Foot 10); in 3.36 last sentence, delete first "X is"; in 4.5 parts 4,5, add superscript Us to Ds; add 7.5; add proof of 10.2 part 3; some small terminology and other minor changes

R2 v1 2026-06-23T22:53:09.867Z