Timeline for Pushforward and pullback.
Current License: CC BY-SA 2.5
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 19, 2016 at 9:13 | answer | added | Szymon Toruńczyk | timeline score: 4 | |
| Dec 14, 2010 at 4:21 | comment | added | Theo Johnson-Freyd | In any case, my "answer" doesn't really deserve the answer box, so I will leave it here as a comment. First, for many applications, I think the difference between pushforward and pullback boils down to the difference between left- and right-adjoints, so I recommend reading about those. Second, and more importantly, the language of fibered categories is pretty much perfect for understanding "things that can be pulled back". With some arrows reverse, you get the right structure for talking about "things that can be pushed forward". | |
| Dec 14, 2010 at 4:17 | comment | added | Theo Johnson-Freyd | There are some good answers below, but as written I don't think that this is a great question. I would be happier if you could encapsulate your question into a phrased-as-a-question title. Perhaps "What is the right way to think about "pushforward" and "pullback"?" is the title you want. If not, you should revise the question and the title. | |
| Dec 14, 2010 at 3:01 | answer | added | Sergey Melikhov | timeline score: 21 | |
| Nov 13, 2010 at 16:13 | answer | added | Deane Yang | timeline score: 8 | |
| Nov 12, 2010 at 2:10 | comment | added | ε-δ | @Deane, I see bunch of examples, but I do not know exact meaning... | |
| Nov 12, 2010 at 0:23 | comment | added | Deane Yang | I don't understand this question. Are you saying that you use these words without understanding their precise meanings? | |
| Nov 11, 2010 at 7:26 | answer | added | Sándor Kovács | timeline score: 10 | |
| Nov 11, 2010 at 7:06 | answer | added | David Carchedi | timeline score: 2 | |
| Nov 11, 2010 at 5:15 | comment | added | David Roberts♦ | Often these arise when you have a(n op)fibred category, and $f^*O_X$ (resp. $f_*O_Y$) arise from (op)cartesian lifts of $f$ (where $X$ and $Y$ sit) to the category your data $O_{(-)}$ lives in. | |
| Nov 11, 2010 at 5:14 | comment | added | Will Jagy | en.wikipedia.org/wiki/… $$ $$ | |
| Nov 11, 2010 at 5:11 | comment | added | David Roberts♦ | Are you asking about the rationale behind the terminology or the idea about what pullback and pushforward are? No one complains because this is established terminology and well-understood operations. Briefly, pushforward and pullback take structure forward or backward along a given arrow. | |
| Nov 11, 2010 at 5:06 | history | asked | ε-δ | CC BY-SA 2.5 |