Bjørn Jahren

• Hausmann, Jean-Claude & Jahren, Bjørn (2019). A simplification problem in manifold topology. L'Enseignement mathématique (LEM).  ISSN 0013-8584.  64(1/2), s 207- 248 . doi: 10.4171/LEM/64-1/2-8 Fulltekst i vitenarkiv.
• Jahren, Bjørn & Kwasik, Slawomir (2018). Whitehead torsion of inertial h-cobordisms. Topology and its Applications.  ISSN 0166-8641.  249, s 150- 159 . doi: 10.1016/j.topol.2018.09.013 Fulltekst i vitenarkiv.
• Jahren, Bjørn & Sławomir, Kwasik (2015). How different can h-cobordant manifolds be?. Bulletin of the London Mathematical Society.  ISSN 0024-6093.  47(4), s 617- 630 . doi: 10.1112/blms/bdv039
• Jahren, Bjørn & Kwasik, Slawomir (2011). Free involutions on S-1 x S-n. Mathematische Annalen.  ISSN 0025-5831.  351(2), s 281- 303 . doi: 10.1007/s00208-010-0599-y
• Jahren, Bjørn (2010). Pseudoisotopies and the Bokstedt trace. Geometriae Dedicata.  ISSN 0046-5755.  148(1), s 245- 261 . doi: 10.1007/s10711-009-9441-7
• Jahren, Bjørn (2009). Involutions on the rational K -theory of group rings of finite groups, In  Alpine Perspectives on Algebraic Topology.  American Mathematical Society (AMS).  ISBN 978-0-8218-4839-5.  Article.  s 189 - 202
• Jahren, Bjørn (2009). Pseudoisotopies and the Bökstedt trace. Geometriae Dedicata.  ISSN 0046-5755. . doi: 10.1007/s10711-009-9441-7
• Jahren, Bjørn & Kwasik, S (2006). Manifolds homotopy equivalent to RP4#RP4. Mathematical proceedings of the Cambridge Philosophical Society (Print).  ISSN 0305-0041.  140
• Jahren, Bjørn (2003). Three-dimensional surgery theory, UNil-groups and the Borel conjecture. Topology.  ISSN 0040-9383.  42, s 1353- 1369
• Jahren, Bjørn (1999). K-theory, flat bundles and the Borel classes. Fundamenta Mathematicae.  ISSN 0016-2736.  161, s 137- 153 Vis sammendrag

  Using Hausmann and Vogel's homology sphere bundle interpretation of algebraic K-theory, we construct K-theory invariants by a theory of characteristic classes for flat bundles. It is shown that the Borel classes are detected this way, as well as the rational K-theory of integer group rings of finite groups.

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• Rognes, John; Jahren, Bjørn & Waldhausen, Friedhelm (2013). Spaces of PL Manifolds and Categories of Simple Maps. Princeton University Press.  ISBN 978-0-691-15775-7.  192 s.
• Baas, Nils A.; Friedlander, Eric M.; Jahren, Bjørn & Østvær, Paul Arne (2009). Algebraic Topology. The Abel Symposium 2007. Springer.  ISBN 978-3-642-01199-3.
• Jahren, Bjørn (ed.) (2006). Motivic Homotopy Theory. Springer.  ISBN 3-540-45895-6.  222 s.

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• Jahren, Bjørn (2017). H-Cobordisms and stabilization of diffeomorphisms.
• Jahren, Bjørn (2016). On the work of Eldar Straume on Transformation Groups.
• Nerland, Stener; Jørgensen, Kjetil Nordbø; Jahren, Bjørn; Melle, Ingrid; Andreassen, Ole Andreas & Agartz, Ingrid (2016). A Topological Characterisation of Cortical Folding in Schizophrenia and Bipolar Disorder.
• Jahren, Bjørn (2015). Inertial and non-inertial h-cobordisms.
• Jahren, Bjørn (2012). H-cobordant manifolds.
• Jahren, Bjørn (2012). How different can h-cobordant manifolds be?.
• Jahren, Bjørn (2012). How different can h-cobordant manifolds be?.
• Jahren, Bjørn (2011). Eksotiske sfærer.
• Jahren, Bjørn (2011). Exotic structures on manifolds.
• Jahren, Bjørn (2011). Fra musikk til algebra og geometri.
• Jahren, Bjørn (2011). Geometric Structures in Dimension two.
• Jahren, Bjørn (2011). Relationships between h-cobordant manifolds.
• Jahren, Bjørn (2010). Supplementary notes for MAT4520, Spring 2010.
• Jahren, Bjørn (2009). Litt om topologisk fikspunktteori.
• Jahren, Bjørn (2008). Topological classification of free involutions on S^1xS^n.
• Jahren, Bjørn (2008). Topological classification of free involutions on S^1xS^n.
• Jahren, Bjørn (2008). Topological classification of free involutions on S^1xS^n.
• Jahren, Bjørn (2007). Topological classification of free involutions on S1xSn.
• Jahren, Bjørn (2007). Topological classification of free involutions on S1xSn.
• Jahren, Bjørn (2007). geometric structures.
• Jahren, Bjørn (2006). Lefschetz-Nielsen teori og homotopi-fikspunkter.
• Jahren, Bjørn (2006). Trace invariants for fixed and periodic points. Oberwolfach Reports.  ISSN 1660-8933.
• Jahren, Bjørn (2006). Trace invariants for fixed and periodic points.
• Jahren, Bjørn & Kwasik, Slawomir (2006). Free involutions on S^1xS^n.
• Jahren, Bjørn; Rognes, John & Waldhausen, Friedhelm (2006). Spaces of PL manifolds and categories of simple maps.
• Jahren, Bjørn (2005). Classification of free involutions on S^1xS^3.
• Jahren, Bjørn (2005). Fixpoints and homotopy fixpoint of maps.
• Jahren, Bjørn (2005). Introduction to surgery theory.
• Jahren, Bjørn (2005). On manifolds homotopy equivalent to RP^4 x RP^4.
• Jahren, Bjørn (2005). On manifolds homotopy equivalent to RP^4#RP^4.
• Jahren, Bjørn (2005). On topological mansilds doubly covered by S^1xS^n.
• Jahren, Bjørn (2005). Some calculations of rational homotopy of diffeomorphism groups.
• Jahren, Bjørn (2005). Topological classification of free involutions of S^1xS^n.
• Jahren, Bjørn (2005). Topological classification of free involutions on S^1 x S^n.
• Jahren, Bjørn (2005). Topological classification of free involutions on S^1xS^n.
• Jahren, Bjørn (2005). Topological classifications of free involutions on S^1xS^n.
• Jahren, Bjørn (2004). A homological formula for the Lefschetz-Reidemeister torsion.
• Jahren, Bjørn (2004). Geometri og geometrier i dimensjon 3 (To foredrag).
• Jahren, Bjørn (2004). Homotoy fixpoints and Nielsen-Lefschetz theory.
• Jahren, Bjørn (2004). Manifolds homotopy equivalent to RP^4#RP^4.
• Jahren, Bjørn (2001). 3-dimensional surgery, UNil-groups and the Borel conjecture.
• Jahren, Bjørn (2001). On surgery in dimension 3.
• Jahren, Bjørn (2001). On surgery in dimension 3.
• Jahren, Bjørn (2001). Problems and results in low-dimensional surgery.
• Jahren, Bjørn (2000). Flat bundles and Borel classes in K-theory.
• Jahren, Bjørn (2000). Flat bundles and Borel classes in K-theory.
• Jahren, Bjørn (2000). Hvorfor er det så trangt i dimensjon 4?.
• Jahren, Bjørn (2000). Hvorfor er det så trangt i dimensjon 4?.
• Jahren, Bjørn (2000). Hvorfor er det så trangt i dimensjon 4?.
• Jahren, Bjørn (2000). Kirurgiobstruksjonen i dimensjon 3.
• Jahren, Bjørn (2000, 17. oktober). Mozart, menuetter og terningkast. [Radio].  "Midt i musikken" : NRK radio, P2.
• Jahren, Bjørn (2000, 18. oktober). Mozart, menuetter og terningkast. [Radio].  "WOK" : NRK, P2.
• Jahren, Bjørn (2000, 18. oktober). Mozart, menuetter og terningkast. [Radio].  Metropol TV.
• Jahren, Bjørn (2000, 18. oktober). Mozart, menuetter og terningkast. [Radio].  Metropol TV.
• Jahren, Bjørn (2000). Topology and geometry of 3-manifolds.
• Jahren, Bjørn (1999). 3-dimensional surgery and the Borel conjecture. Vis sammendrag

  The Borel conjecture asserts that closed aspherical manifolds are determined up to homeomorphism by their fundamental groups. The general conjecture is still open, but it has been proved for classes of manifolds satisfying certain geometric properties. Using surgery theory in dimension three and stabilizing, we show that the assertion holds for new classes of manifolds, and we also discuss the possibilities of counterexamples to Borel's conjecture. This is joint work with Slawomir Kwasik, Tulane University.

• Jahren, Bjørn & Kwasik, Slawomir (1999). 3-dimensional surgery, UNil and the Borel conjecture.

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