Timeline for What does $\pi$ in the term $\pi$-system stand for?
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 13, 2020 at 14:36 | comment | added | Pietro Majer | Operations denoted by $\prod$, $\bigwedge$, $\bigcap$, etc usually share the same universal property (being some inverse limit of a discrete system) and so do their duals $\coprod$, $\bigvee$, $\bigcup$, (direct limits). So the choice $\pi$ to allude to $\cap$ is very natural. The reason for $\lambda$ is likely to be the one mentioned by Carlo Beenakker | |
| Aug 12, 2017 at 18:13 | history | edited | Henry.L | CC BY-SA 3.0 |
new ideas added
|
| Jun 19, 2017 at 14:14 | comment | added | Henry.L | @CarloBeenakker I agree that sometimes symbols are chosen without specific reasons, but when theories build up these meaningless symbols will usually be replaced by more carefully chosen new terms, "path-dependence of terms" is very rare in math, while this probably one... | |
| Jun 19, 2017 at 13:20 | comment | added | Carlo Beenakker | this is interesting, but I wonder why symbols for mathematical objects need a reason to be chosen by the author; $\pi$, $\lambda$, $\rho$, $\sigma$, $\tau$ --- in papers I read these symbols tend to be just chosen because they are not yet taken, without a deeper reason. | |
| Jun 19, 2017 at 13:09 | history | answered | Henry.L | CC BY-SA 3.0 |