Timeline for How velocity dispersion changes with change of inertial frame
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Nov 28, 2014 at 12:26 | comment | added | zephyr | What other ways are there to define it? As far as I can see the two ways I've presented are just the most fundamental way of calculating velocity dispersion in the "lab" and CoM frame respectively, but maybe I've missed something? | |
| Nov 27, 2014 at 15:57 | history | edited | user65081 | CC BY-SA 3.0 |
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| Nov 27, 2014 at 15:49 | comment | added | user65081 | there are different ways to define it, but if you use your definition onviously it will differ. | |
| Nov 27, 2014 at 15:32 | comment | added | zephyr | so I would definitely agree with this in 1 dimension, when velocity and speed are effectively interchangeable, but seeing as we find the relative velocities in any one of the three cartesian dimensions by subtracting off the CoM velocity from the original velocity then it seems like sum(v^2 - v(com)^2) will differ from sum|v(rel)| where the sums are over all stars in the galaxy (n.b. sorry for the awful notation but can't do LaTeX in comments can I?) | |
| Nov 27, 2014 at 15:26 | history | edited | user65081 | CC BY-SA 3.0 |
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| Nov 27, 2014 at 15:03 | history | answered | user65081 | CC BY-SA 3.0 |