تقرير
Symmetric orthogonality and non-expansive projections in metric spaces
| العنوان: | Symmetric orthogonality and non-expansive projections in metric spaces |
|---|---|
| المؤلفون: | Kell, Martin |
| سنة النشر: | 2016 |
| المجموعة: | Mathematics |
| مصطلحات موضوعية: | Mathematics - Metric Geometry, Mathematics - Differential Geometry |
| الوصف: | In this paper known results of symmetric orthogonality, as introduced by G. Birkhoff, and non-expansive nearest point projections are extended from the linear to the metric setting. If the space has non-positive curvature in the sense Busemann then it is shown that those concepts are actually equivalent. In the end it is shown that every space having non-positive curvature in the sense of Busemann is a $CAT(0)$-space provided that its tangent cones are uniquely geodesic and their nearest point projections onto convex are non-expansive. Comment: 15 pages. Simplified presentation, removed Pedersen convexity, more direct proof of Theorem 19. Comments welcome! |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/1604.01993 |
| رقم الأكسشن: | edsarx.1604.01993 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |