Title Small differences between cubic and rational numbers
Authors Dubickas, Artūras
DOI 10.1017/S0017089526100998
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Is Part of Glasgow mathematical journal.. Cambridge : Cambridge University Press. 2026, Early Access, p. [1-8].. ISSN 0017-0895. eISSN 1469-509X
Keywords [eng] approximation to algebraic numbers ; continued fraction ; cubic number ; irreducibility
Abstract [eng] In this paper,we showthat for each sufficiently large integerH, there is a real cubic number α and a rational number r, both of height smaller than H, such that 0<α −r <272/H4. The exponent 4 of H in this inequality is best possible. The numbers α and r are both constructed explicitly.We also show that a necessary and sufficient condition on (u, v) under which there is a positive constant c1 =c1(d, u, v) such that the inequality |α −β| ≥ c1H(α)−uH(β)−v holds for all real algebraic numbers α of degree d ≥ 2 and all real algebraic numbers β of degree d −1 is u ≥ d −1 and v ≥ d.
Published Cambridge : Cambridge University Press
Type Journal article
Language English
Publication date 2026
CC license CC license description