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arXiv · 1209.3933

Borel* Sets in the Generalised Baire Space

Tapani Hyttinen·Vadim Kulikov
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Abstract

We start by giving a survey to the theory of Borel*(κ) sets in the generalized Baire space Baire(κ) = κ^κ. In particular we look at the relation of this complexity class to other complexity classes which we denote by Borel(κ), Δ^1_1(κ) and Σ^1_1(κ) and the connections between Borel*(κ)-sets and the infinitely deep language M_{κ^+κ}. In the end of the paper we prove the consistency of Borel*(κ) \ne Σ^1_1(κ).

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BibTeXRIS

Tapani Hyttinen, Vadim Kulikov. 2012-09-18. Borel* Sets in the Generalised Baire Space. https://arxiv.org/abs/1209.3933

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