文摘
Given a theory T of a polynomially bounded o-minimal expansion R of \({\bar{\mathbb{R}} = \langle\mathbb{R}, +, ., 0, 1, < \rangle}\) with field of exponents \({\mathbb{Q}}\), we introduce a theory \({\mathbb{T}}\) whose models are expansions of dense pairs of models of T by a discrete multiplicative group. We prove that \({\mathbb{T}}\) is complete and admits quantifier elimination when predicates are added for certain existential formulas. In particular, if T = RCF then \({\mathbb{T}}\) axiomatises \({\langle\bar{\mathbb{R}}, \mathbb{R}_{alg}, 2^{\mathbb{Z}}\rangle}\), where \({\mathbb{R}_{alg}}\) denotes the real algebraic numbers. We describe types and definable sets in our models and prove that \({\mathbb{T}}\) is dependent. Keywords O-minimality Dense pairs Integer powers of two