Recent content by dookie

well, it doesn't really matter whether or not you think I'm ready to study this because i have to, since I'm taking the course (and don't tell me to withdraw, too late) and i didn't really miss the point of the problem, since i already discussed it with my professor and turned in the...

given that i no longer really need the answer (but would still very much appreciate understanding it), i wasn't going to dig out the book but here it is: problem book in relativity and gravitation, lightman et al the problem: "show that once a rocket ship" (the observer) "crosses the...

in any case if it IS for just the interior region of a schwarzschild black hole why is that so? because r becomes time-like and t becomes space-like? what does that mean physically?

ds^2 = (1-2m/r) \, dt^2 -(1-2m/r)^-1 \, dr^2 - r^2 \, d\Omega^2 this is the schwarzschild metric as stated in wald

i was speaking of the kruskal extension, so I'm referring to the schwarzschild black hole model with the standard schwarzschild metric. my textbook is wald so I'm assuming everything he uses is pretty much standard. I'm not sure whether this derivative is supposed to be negative inside the event...

=( please help me, i know this has to be simple

i am trying to understand why dr/dTau must be negative for a future-directed (physical) observer in the Schwarzschild metric. it says "we also know (e.g. from the Kruskal picture) that the sign of dr/dTau must be negative for a "future-directed" (i.e. physical) observer" i am probably...

oh do you mean can it satisfy the geodesic equation ? (sorry) if so then i believe it can only do so when theta equals a multiple of pi/2 (the equator). (or the poles, but those wouldn't count as lines of latitude). and i did mean to post that i realized last night that the way i did this...

well i am looking at it in the sense that we are keeping constant theta, and somehow mapping out a curve on the manifold, so one variable has to run from one value to another. with constant theta, to make a line of latitude (a circle, not necessarily great circle, on the 2-sphere), we need phi...

well I'm not sure that phi does change at a constant rate. i thought it did but it may not. does anyone know whether it does, in lines of constant latitude?

Homework Statement Consider a 2-sphere of radius R parametrized by the 2 spherical polar coordinates θ and φ. Write down the standard metric in these coordinates. 1. Show that lines of constant longitude are geodesics, and that the only line of constant latitude is the equator. 2. How...