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Jul 25, 2014 at 15:19 comment added kaveh Tobias, I agree, it would be better if he put more details; it is a bit hard to follow this work. However, this paper is quit interesting and I think this definition of $\beta$-cotangent bundle is suitable for my purpose which is getting a Finsler structure on a cotangent bundle by using pairing. He says that the $\beta$-exterior bundle is locally trivial if all continuous linear maps, map the bornology into itself, but I dont know how often can it occurs in practice.
Jul 25, 2014 at 13:02 comment added Tobias Diez It's a long time since I looked at Prof. Wurzbachers work, so take the following with a grain of salt: I wasn't to convince that his definition of a cotangent bundle does not run in the same kind of complications, i.e. it is not locally trivial in a smooth manner (since the above result of Neeb yields a counter example for every vector space topology on the dual). If I remember it correctly, Wurzbacher just says "this bundle is obviously locally trivial" and don't comment on possible issues. Kaveh, do you think his work is rigorous?
Jul 25, 2014 at 12:29 comment added kaveh Thanks for comments, It seems that there is a replacement for a cotangent bundle with a manifold structure in standard calculus (Michal and Bastiani). If we define the topology of uniform convergence on all compact sets of a cotangent space. If $\beta$ is a bornology on the model space. Then the $\beta$-cotangent bundle which is the union of the cotangent spaces with the above topology has a structure of a manifold, see Wurzbacher, Fermionic Second Quantization.
Jul 25, 2014 at 7:35 comment added Tobias Diez You can still form the exterior bundle (and in particular the cotangent bundle) in the set-theoretic sense. So the differential $df$ still belongs to the cotangent bundle, however you don't have a smooth structure on it and thus you cannot say that the map $m \mapsto (df)_m$ is smooth in the usual way.
Jul 24, 2014 at 21:14 comment added TaQ @ Kaveh Eftekharinasab: If instead of the Michal−Bastiani smoothness you choose to use the Frölicher−Kriegl−Michor "Convenient Calculus", then you can construct the cotangent bundle in the usual manner. However, then there is the drawback that a smooth map with domain a nonmetrizable space need not be continuous.
Jul 24, 2014 at 19:05 comment added kaveh Thanks, it was suggested a replacement for a cotangent bundle which is a sub-bundle of the cotangent bundle with a natural smooth structure (Neeb, Remark II.3.5, Monastir Summer School: Infinite-Dimensional Lie Groups). A question which arise now is that if we have for example a functional f on manifold the differential df is the element of the cotangent bundle, is there a replacement of the cotangent bundle which df belongs to?
Jul 24, 2014 at 11:19 history answered Tobias Diez CC BY-SA 3.0