Article

Multiplicative zero-one laws and metric number theory

Acta Arithmetica (Impact Factor: 0.42). 12/2010; DOI: 10.4064/aa160-2-1
Source: arXiv

ABSTRACT We develop the classical theory of Diophantine approximation without assuming
monotonicity or convexity. A complete `multiplicative' zero-one law is
established akin to the `simultaneous' zero-one laws of Cassels and Gallagher.
As a consequence we are able to establish the analogue of the Duffin-Schaeffer
theorem within the multiplicative setup. The key ingredient is the rather
simple but nevertheless versatile `cross fibering principle'. In a nutshell it
enables us to `lift' zero-one laws to higher dimensions.

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