Timeline for maximum decay rate
Current License: CC BY-SA 2.5
7 events
| when toggle format | what | by | license | comment | |
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| May 10, 2010 at 3:58 | comment | added | Harald Hanche-Olsen | The wave travels outward at speed 1. Hence, for large $t$, $r$ and $t$ are asymptotically equal where $u\ne0$. | |
| May 10, 2010 at 3:48 | comment | added | chris | i am being a bit dense here, why does decay @ $1/r$ imply decay @ $1/t$? | |
| May 10, 2010 at 0:22 | comment | added | chris | oh i wasn't thinking at all =) thanks, that cleared it up a lot | |
| May 10, 2010 at 0:21 | vote | accept | chris | ||
| May 10, 2010 at 0:12 | comment | added | Harald Hanche-Olsen |
That's the “wave” in “wave equation”. The general solution of $v_{tt}-v_{rr}=0$ is $f(r-t)+g(r+t)$ for functions $f$, $g$. After the $g$ contribution has left the region $r>0$, only $f(r-t)$ remains. I.e., constant shape.
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| May 9, 2010 at 23:19 | comment | added | chris | why does it have a constant shape? | |
| May 9, 2010 at 21:14 | history | answered | Harald Hanche-Olsen | CC BY-SA 2.5 |