Open Questions in The Theory of Spaces of Orderings
نویسنده
چکیده
Spaces of orderings provide an abstract framework in which to study spaces of orderings of formally real fields. Spaces of orderings of finite chain length are well understood [9] [12]. The Isotropy Theorem [12] and the extension of the Isotropy Theorem given in [13] are the main tools for reducing questions to the finite case, and these are quite effective. At the same time, there are many questions which do not appear to reduce in this way. In this paper we consider four such questions, for a space of orderings (X,G).
منابع مشابه
The pp conjecture for spaces of orderings of rational conics
First counterexamples are given to a basic question raised in: M. Marshall, Open questions in the theory of spaces of orderings, J. Symbolic Logic 67 (2002), 341352. The paper considers the space of orderings (X,G) of the function field of a real irreducible conic C over the field Q of rational numbers. It is shown that the pp conjecture fails to hold for such a space of orderings when C has no...
متن کاملIdentifying the Needs of Young People in Establishing Social Interactions in the Context of Temporary Landscape of Mashhad Based on Grounded Theory
Aims & Backgrounds: With the development of technology, time has become more limited to the presence of urban spaces and the experience of spaces and visual relations. This means that in the process of fitting the urban environment it is necessary to create spaces in which that, meanwhile in accordance with the needs of today, fit beyond the obvious qualities of space. In these spaces, we must ...
متن کاملThe pp conjecture for the space of orderings
The paper considers the space of orderings (XR(x,y), GR(x,y)) of the field of rational functions over R in two variables. It is shown that the pp conjecture fails to hold for such a space; an example of a positive primitive formula which is not product-free and one-related is investigated and it is proven, that although the formula holds true for every finite subspace of (XR(x,y), GR(x,y)), it ...
متن کاملنقش جغرافیا در شکلگیری انواع حیاط در خانههای سنتی ایران
Extended Abstract Introduction The formation of built spaces in composition to open spaces is one of the important subjects in designing architectural spaces. Different factors were important in formation of open spaces in traditional architecture. The kind of function of a building was one of these factors, because the quality of designing courtyards and its elements were dependent to the ...
متن کاملOn Generalized Injective Spaces in Generalized Topologies
In this paper, we first present a new type of the concept of open sets by expressing some properties of arbitrary mappings on a power set. With the generalization of the closure spaces in categorical topology, we introduce the generalized topological spaces and the concept of generalized continuity and become familiar with weak and strong structures for generalized topological spaces. Then, int...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- J. Symb. Log.
دوره 67 شماره
صفحات -
تاریخ انتشار 2002