Tag Info

New answers tagged

0

Make sure when you vary your first equation that you use a different index instead of $n$. Do the following: $$\frac{\delta U^{harm}}{\delta u(ma)}$$ this gives $$ \frac{1}{2}K \sum_{n} 2 [u(na) - u([n+1]a)]\left[\frac{\delta u(na)}{\delta u(ma)} - \frac{\delta u([n+1]a)}{\delta u(ma)} \right] $$ by the chain rule. But $$ \frac{\delta u(na)}{\delta ...



Top 50 recent answers are included