Talk:Colombeau algebra

Latest comment: 1 month ago by 2603:8080:23F0:AE40:C76:2841:4EAA:7671 in topic Doubtful

You do not explain what f-sub-epsilon is, you write f:C-infinity(Rn) -> R+ while, I believe, you mean that f: Rn -> R+

Please make proper changes, so that the article really explains what the Colombeau algebra is.

Best regards

htg@interia.pl —Preceding unsigned comment added by 83.30.190.229 (talkcontribs) 17:50, 24 August 2006

I fixed this error (nonsense introduced by an anonymous contributor), and several other wrong statements. It's still not perfect (the following "such that" is not very useful), but it should be clear now (nets are functions of the index epsilon, and for given epsilon one gets a C°° function on R^n)... — MFH:Talk 21:13, 28 February 2008 (UTC)Reply

Definition sources confusion

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I noticed that the definition given in the Basic idea section coincides with Section 8.5 in Colombeau's Multiplication of distributions, but it has no straightforward relation to Gratus's notes, which is the source cited for it. Perhaps this ought to be corrected/clarified. Thanks. Zatrp (talk) 13:16, 4 August 2023 (UTC)Reply

Doubtful

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I doubt Colombeau theory is widely used in applications - I haven't seen it used. The article says "These algebras have found numerous applications in the fields of partial differential equations, geophysics, microlocal analysis and general relativity so far" but it doesn't point to a single one. When I see people multiplying distributions, they use Hormander's product theorem, involving the concept of wavefront set. So I think this article should convey a more accurate assessment of Colombeau theory and why people don't use it much. John Baez (talk) 15:16, 30 August 2024 (UTC)Reply

Why don't people use it much, do you reckon? Is it hard to use? Badly exposited? Or wrong somehow? 2603:8080:23F0:AE40:C76:2841:4EAA:7671 (talk) 07:28, 10 September 2024 (UTC)Reply