Timeline for A characterization of Hilbert spaces?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 15, 2013 at 23:39 | comment | added | Włodzimierz Holsztyński | @Sergei, your theorem/proof is very-very nice, you had an idea after an idea. | |
| May 15, 2013 at 23:38 | vote | accept | Włodzimierz Holsztyński | ||
| May 15, 2013 at 7:13 | comment | added | Włodzimierz Holsztyński | @Sergei, somehow I missed your answer, I discovered your answer just a moment ago, I am really sorry. I'll carefully read your answer within 24h, and will comment on it (even if I will not get it :-), but at least I will admit it). | |
| May 13, 2013 at 9:54 | comment | added | Sergei Ivanov | @Bill: this is plausible but I don't know for sure. In finite dimensions, you can differentiate the map at some point and get that a codimension 1 section is within a bounded distance from a Euclidean norm. I don't know how to carry this over to infinite dimensions. | |
| May 13, 2013 at 7:43 | comment | added | Bill Johnson | Nice, Sergei. If some duality map is biLipschitz, then must the Banach space be isomorphic to a Hilbert space? I have a (possibly false) recollection that this is true but don't see a proof. | |
| May 12, 2013 at 22:16 | history | answered | Sergei Ivanov | CC BY-SA 3.0 |