Next post was intended to be an estimation of energy needed for warping spacetime, but its going to take a little more of time since I have to do some checkup on math -and procedure.
So, in the mean time... :)
... I've already said I'm not very fond of hearing classes. In general it is quite truth, but in my quest for understanding spacetime, several internet searches have leaded me to actual videos of classes. Which is a little ironic, I guess...
Anyway, MIT online courses are a good source of info in a lot of very interesting things in engineering and sciences. Lecture notes, slide presentations and some classes recorded in video are available and easy to find.
The video is a lecture made by Edmund Bertschinger about Einstein field equations, introductory level. I'm not sure of the year, but that pullover seems not very new. It overviews -the class, not the pullover- a couple of interesting ideas:
- During 15 first minutes, Newton gravitational laws are introduced with some of its generalizations.
- It presents geodesic equations as a result of applying Euler-Lagrange equations over metric components -that's it: how space tells matter how to move -about minute 20 to 23
- About minute 40 Bertschinger starts talking about the requeriments General Relativity has to accomplish and touches a concept I didn't know: gravitational fields can induce or modify other gratitational fields. I should put a little effort in looking for this concept later.
- By the end of the video, it is presented what the T tensor means and a brief description, which is quite useful actually.
You can check the video here.
I know there are others "online" classes not only by MIT but by Stanford teacher at the moment Leonard Susskind. I tried to watch Susskind classes about GR a couple of years ago... Maybe now I'm a little more prepared...
No comments:
Post a Comment