We study the model theory of the ring of adeles of a number field. We obtain quantifier elimination results in the language of rings and some enrichments. We given consequences for definable subsets of the adeles, and their measures.
This paper is a survey on model theory of adeles and applications to model theory, algebra, and number theory. Sections 1-12 concern model theory of adeles and the results are joint works with Angus Macintyre. The topics covered include quantifier elimination in enriched Boolean algebras, quantifier elimination in restricted products and in adeles and adele spaces of algebraic varieties in natural languages, definable subsets of adeles and their measures, solution to a problem of Ax from 1968 on decidability of the rings $\mathbb{Z}/m\mathbb{Z}$ for all $m>1$, definable sets of minimal idempot…
We prove quantifier elimination for the theory of quasi-real closed fields with a compatible valuation. This unifies the same known results for algebraically closed valued fields and real closed valued fields.
Let $R$ be an o-minimal expansion of a group in a language in which $\textrm{Th}(R)$ eliminates quantifiers, and let $C$ be a predicate for a valuational cut in $R$. We identify a condition that implies quantifier elimination for $\textrm{Th}(R,C)$ in the language of $R$ expanded by $C$ and a small number of constants, and which, in turn, is implied by $\textrm{Th}(R,C)$ having quantifier elimination and being universally axiomatizable. The condition applies for example in the case when $C$ is a convex subring of an o-minimal field $R$ and its residue field is o-minimal.
St Hilda's College, University of Oxford(牛津大学圣希尔达学院);St Peter's College, University of Oxford(牛津大学圣彼得学院);Mathematical Institute, University of Oxford(牛津大学数学研究所)
These are lecture notes for a course I gave in mid-1990s for MSc students at the University of Bath. It presents an algorithm with singly exponential complexity for the existential theory of the reals, in the spirit of J. Renegar. The aim was to convey the main underlying ideas, so many of the proofs and finer details of algorithms are either missing or just sketched. I changed nothing in the original notes except adding references, bibliography, and correcting obvious typos.
Quantifier elimination in quasianalytic structures via non-standard analysis
本文是我们以前的文章,我们开发了一个理论的积极和非积极的无穷小,并打算建立量词消除准解析结构的延续。这篇文章,但是,没有达到充分的一般性,这是指其结果之一,即定理的积极无穷小,发挥了重要作用,在我们的非标准分析。我们随后的预印本中涵盖了一般情况,这构成了本文所述方法的基础。我们还提供了一个quasianalytic阐述的结果rectlinearization的条款和可定义的功能,从我们以前的研究。它将被用来证明一个准解析结构对应的Denjoy-Carleman类,不像经典的分析结构,不承认量词消除语言的限制准解析函数增加的倒数函数。更准确地说,我们构造了一条平面可定义曲线,这表明J. Denef和L. van den Dries和Jasojasiewicz的定理,即每一条次解析曲线都是半解析的,对于拟解析结构不再成立。除了直线性化的条款,我们的建设利用一些定理的权力替代Denjoy-Carleman类和拟解析函数芽的非可拓性。最后一个结果依赖于(LF)-空间的Grothendieck因子分解定理和开映射定理.最后请注意,这篇论文包含了我们在2012年5月关于这个主题的早期预印本。
We introduce a formal logical language, called conditional probability logic (CPL), which extends first-order logic and which can express probabilities, conditional probabilities and which can compare conditional probabilities. Intuitively speaking, although formal details are different, CPL can express the same kind of statements as some languages which have been considered in the artificial intelligence community. We also consider a way of making precise the notion of lifted Bayesian network, where this notion is a type of (lifted) probabilistic graphical model used in machine learning, data…
Let $X \subset \mathbb{P}^{n}$ be a non-empty closed subscheme over an algebraically closed field $k$, and $\mathrm{J}^{[p]}(X) = \mathrm{J}(X,\mathrm{J}(X,\cdots,\mathrm{J}(X,X)\cdots)$ denote the $p$-fold iterated join of $X$ with itself. In this article, we prove that the restriction homomorphism on cohomology $\mathrm{H}^{i}(\mathbb{P}^{N}) \rightarrow \mathrm{H}^{i}(\mathrm{J}^{[p]}(X))$, with $N = (p+1)(n+1)-1$, is an isomorphism for $0 \leq i < p$, and injective for $i=p$, for any good cohomology theory. We also prove this result in the more general setting of relative joins for $X$ ove…
We prove some results about the model theory of fields with a derivation of the Frobenius map, especially that the model companion of this theory is axiomatizable by axioms used by Wood in the case of the theory $\operatorname{DCF}_p$ and that it eliminates quantifiers after adding the inverse of the Frobenius map to the language. This strengthens the results from [4]. As a by-product, we get a new geometric axiomatization of this model companion. Along the way we also prove a quantifier elimination result, which holds in a much more general context and we suggest a way of giving "one-dimensio…
The ordered structures of natural, integer, rational and real numbers are studied in this thesis. The theories of these numbers in the language of order are decidable and finitely axiomatizable. Also, their theories in the language of order and addition are decidable and infinitely axiomatizable. For the language of order and multiplication, it is known that the theories of $\mathbb{N}$ and $\mathbb{Z}$ are not decidable (and so not axiomatizable by any computably enumerable set of sentences). By Tarski's theorem, the multiplicative ordered structure of $\mathbb{R}$ is decidable also. In this …