Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with variational-principle
Search options not deleted
user 220348
Any of several principles that find the physical trajectory of a system by minimizing or maximizing some value computed over the proposed path (for instance geometric optics can be reproduced by insisting on a minimum time principle).
0
votes
0
answers
84
views
Nambu-Goto action using ADM metric
I start from the Nambu-Goto action:$$
S=-\frac{T_{0}}{c} \int_{\tau_{i}}^{\tau_{f}} d \tau \int_{0}^{\sigma_{1}} d \sigma \sqrt{\left(\dot{X} \cdot X^{\prime}\right)^{2}-(\dot{X})^{2}\left(X^{\prime} …
- 99
2
votes
3
answers
131
views
Motivation behind action when deriving ''Strings as Harmonic oscillators" in Zwiebach's book...
Page 248 gives us this action and he simply says that we will assume it correct.
$$
S=\int d \tau d \sigma ~\mathcal{L}=\frac{1}{4 \pi \alpha^{\prime}} \int d \tau \int_{0}^{\pi} d \sigma\left(\dot{X …
- 99
-1
votes
Motivation behind action when deriving ''Strings as Harmonic oscillators" in Zwiebach's book...
$$
\delta S=\int_{\tau_{i}}^{\tau_{f}} d \tau\left[\delta X^{\mu} \mathcal{P}_{\mu}^{\sigma}\right]_{0}^{\sigma_{1}}-\int_{\tau_{i}}^{\tau_{f}} d \tau \int_{0}^{\sigma_{1}} d \sigma \delta X^{\mu}\lef …
- 99