New Directions in Descriptive Set Theory

  title={New Directions in Descriptive Set Theory},
  author={Alexander S. Kechris},
  journal={Bulletin of Symbolic Logic},
  pages={161 - 174}
  • A. Kechris
  • Published 1 June 1999
  • Mathematics
  • Bulletin of Symbolic Logic
§1. I will start with a quick definition of descriptive set theory: It is the study of the structure of definable sets and functions in separable completely metrizable spaces. Such spaces are usually called Polish spaces. Typical examples are ℝ n , ℂ n , (separable) Hilbert space and more generally all separable Banach spaces, the Cantor space 2ℕ, the Baire space ℕℕ, the infinite symmetric group S∞, the unitary group (of the Hilbert space), the group of measure preserving transformations of the… 

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