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Sep 19, 2023 at 11:49 history edited Matthias Ludewig CC BY-SA 4.0
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Jan 17, 2022 at 15:57 vote accept Matthias Ludewig
Jan 14, 2022 at 8:27 history edited Matthias Ludewig CC BY-SA 4.0
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Jan 14, 2022 at 1:49 answer added Narutaka OZAWA timeline score: 6
Jan 13, 2022 at 12:02 comment added Matthias Ludewig Yes, I think so! How do you show this? Can you give an answer containing a proof or a reference?
Jan 13, 2022 at 4:44 comment added Narutaka OZAWA The map $V(A,H)\to\operatorname{Hom}(A,B(H))$ is open. Is this good enough?
Jan 13, 2022 at 2:27 comment added Nik Weaver @MatthiasLudewig thank you, that helps a lot.
Jan 13, 2022 at 0:05 comment added Dmitri Pavlov @MatthewDaws: In the simplest case, the questions asks whether given a continuous path p:[0,1]→Hom(A,B(H)) together with a lift v∈V(A,H) of p(0), we can construct a continuous path q:[0,1]→V(A,H) that lifts p and such that q(0)=v. The general condition asks the same question in continuous families indexed by disks.
Jan 12, 2022 at 21:37 comment added Matthias Ludewig I added some more about the motivation below the question in the post above.
Jan 12, 2022 at 21:34 comment added Matthias Ludewig Sorry if I appeared blunt, this was not the intention. If Serre fibration does not mean much to you, you can take it to mean "fiber bundle" or any other kind of fibration. The definition linked by Jon Bannon is the one to use. Or the one on Wikipedia (en.wikipedia.org/wiki/Fibration).
Jan 12, 2022 at 14:21 comment added Nik Weaver @MatthiasLudwig, if you're asking for help on something and someone asks you to define an unfamiliar term, this is not a great way to respond. BTW Matthew Daws is very active on mathoverflow and solves a lot of hard problems posed here, so you're really not doing yourself a favor by telling him "the question is perfectly sensible" and refusing to provide a definition.
Jan 12, 2022 at 12:51 comment added Jon Bannon So the definition one should be looking at is found at the following link, or is there a better equivalent condition you are working with? Serre fibrations aren't that familiar to some folks working in vNas. encyclopediaofmath.org/wiki/Serre_fibration
Jan 12, 2022 at 10:41 comment added Matthias Ludewig I defined two sets and a sujective continuous map between them. I would say that the question whether this map is a Serre fibration is perfectly sensible. I also added something about what I tried in the post above.
Jan 12, 2022 at 10:41 history edited Matthias Ludewig CC BY-SA 4.0
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Jan 12, 2022 at 9:52 history edited Matthias Ludewig CC BY-SA 4.0
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Jan 12, 2022 at 9:20 comment added Matthew Daws As a complete non-expert, I looked up "Serre fibration" on wikipedia, and I have to say I could not make sense of the definition, as applied in this case. Could you say a bit more about what one would need to prove, and where in particular you get stuck?
Jan 12, 2022 at 9:16 history asked Matthias Ludewig CC BY-SA 4.0