Currently displaying 1 – 9 of 9

Showing per page

Order by Relevance | Title | Year of publication

Dense pairs of o-minimal structures

Lou van den Dries — 1998

Fundamenta Mathematicae

The structure of definable sets and maps in dense elementary pairs of o-minimal expansions of ordered abelian groups is described. It turns out that a certain notion of "small definable set" plays a special role in this description.

Extending Tamm's theorem

Lou van den DriesChris Miller — 1994

Annales de l'institut Fourier

We extend a result of M. Tamm as follows: Let f : A , A m + n , be definable in the ordered field of real numbers augmented by all real analytic functions on compact boxes and all power functions x x r : ( 0 , ) , r . Then there exists N such that for all ( a , b ) A , if y f ( a , y ) is C N in a neighborhood of b , then y f ( a , y ) is real analytic in a neighborhood of b .

Fields of surreal numbers and exponentiation

Lou van den DriesPhilip Ehrlich — 2001

Fundamenta Mathematicae

We show that Conway's field of surreal numbers with its natural exponential function has the same elementary properties as the exponential field of real numbers. We obtain ordinal bounds on the length of products, reciprocals, exponentials and logarithms of surreal numbers in terms of the lengths of their inputs. It follows that the set of surreal numbers of length less than a given ordinal is a subfield of the field of all surreal numbers if and only if this ordinal is an ε-number. In that case,...

Triangulation in o-minimal fields with standard part map

Lou van den DriesJana Maříková — 2010

Fundamenta Mathematicae

In answering questions of J. Maříková [Fund. Math. 209 (2010)] we prove a triangulation result that is of independent interest. In more detail, let R be an o-minimal field with a proper convex subring V, and let st: V → k be the corresponding standard part map. Under a mild assumption on (R,V) we show that a definable set X ⊆ Vⁿ admits a triangulation that induces a triangulation of its standard part st X ⊆ kⁿ.

Page 1

Download Results (CSV)