Schwarzschild geometry Definition and 28 Threads

  1. H

    I Geodesics in Schwarzschild: Reparametrizing the Equations

    Hi all, I am working through Sean Carroll's Textbook, particularly Chapter 5 regarding the Schwarzschild Solution. In this chapter, Energy and Angular Momentum are defined as follows: $$ \begin{align} E &= (1-\frac{2GM}{r})\frac{dt}{d\lambda} \Rightarrow \frac{dt}{d\lambda} = (1-...
  2. cianfa72

    I Spacetime coordinate smoothness requirement

    Hi, I was keep reading the interesting book Exploring Black Holes - second edition from Taylor, Wheeler, Bertschinger. I'd like to better understand some points they made. In Box 3 section 3-6 an example of coordinate singularity at point O in Euclidean plane in polar coordinates centered there...
  3. G

    A How to Express the Schwarzschild Metric in Fermi Normal Coordinates?

    I have been learning a bit about Fermi normal coordinates in Eric Poisson's "A Relativist's Toolkit". Problem 1.10 in this book is to express the Schwarzschild metric in Fermi normal coordinates about a radially infalling, timelike geodesic. I know that in the Fermi normal coordinates (denoted...
  4. J

    I Schwarzschild Geometry: Einstein Tensor & Mass Density

    The Einstein tensors for the Schwarzschild Geometry equal zero. Why do they not equal something that has to do with the central mass, given that the Einstein equations are of the form: Curvature Measure = Measure of Energy/Matter Density?
  5. kirkr

    A Schwarzschild Geometry: Evaluating Proper Distance

    Schwarzschild Geometry-proper distance. From what I have studied when the Schwarzschild line element is evaluated at constant time and at a constant radius , proper distance becomes a Euclidean distance on the surface of a sphere. What I don't understand is how to evaluate the integral...
  6. cianfa72

    I Coord. Time Vector Field: Schwarzschild vs Gullstrand-Painleve

    Hi, I was reading this insight schwarzschild-geometry-part-1 about the transformation employed to rescale the Schwarzschild coordinate time ##t## to reflect the proper time ##T## of radially infalling objects (Gullstrand-Painleve coordinate time ##T##). As far as I understand it, the vector...
  7. stevendaryl

    A Computing Null Geodesics in Schwarzschild Geometry

    Computing timelike geodesics in the Schwarzschild geometry is pretty straightforward using conserved quantities. You can treat the problem as a variational problem with an effective Lagrangian of ##\mathcal{L} = \frac{1}{2} (Q \frac{dt}{d\tau}^2 - \frac{1}{Q} \frac{dr}{d\tau}^2 - r^2...
  8. T

    A poor man's way to Schwarzschild Geometry

    Can anyone help me get started with this problem? What should I use for Gni? I've tried to produce Tni by working out Rni (using methods developed in an earlier chapter) but the results don't lead me anywhere. I'm really stuck for a way forward on this problem so if anyone can help, it...
  9. George Keeling

    I Understanding Killing Vectors & Schwarzschild Geodesics

    I'm on to section 5.4 of Carroll's book on Schwarzschild geodesics and he says stuff in it which, I think, enlightens me on the use of Killing vectors. I had to go back to section 3.8 on Symmetries and Killing vectors. I now understand the following: A Killing vector satisfies $$...
  10. nabil23

    B Question on Schwarzschild Geometry

    please interpret this observation. There is a specific radius through a given equation that always gives the correct mass to any star or planet, as well a density. What is the logical explanation for this? Mass = (4π/3) x schwarzschild radius of the star x 4π/3 x (726696460.5 cm.) cube. For...
  11. M

    A EoM in Schwarzschild geometry: geodesic v Hamilton formalism

    Hi there guys, Currently writing and comparing two separate Mathematica scripts which can be found here and also here. The first one I've slightly modified to suit my needs and the second one is meant to reproduce the same results. Both scripts are attempting to simulate the trajectory of a...
  12. PeterDonis

    Insights The Schwarzschild Geometry: Part 4 - Comments

    PeterDonis submitted a new PF Insights post The Schwarzschild Geometry: Part 4 Continue reading the Original PF Insights Post.
  13. PeterDonis

    Insights The Schwarzschild Geometry: Part 3 - Comments

    PeterDonis submitted a new PF Insights post The Schwarzschild Geometry: Part 3 Continue reading the Original PF Insights Post.
  14. PeterDonis

    Insights The Schwarzschild Geometry: Part 2 - Comments

    PeterDonis submitted a new PF Insights post The Schwarzschild Geometry: Part 2 Continue reading the Original PF Insights Post.
  15. PeterDonis

    Insights The Schwarzschild Geometry: Part 1 - Comments

    PeterDonis submitted a new PF Insights post The Schwarzschild Geometry: Part 1 Continue reading the Original PF Insights Post.
  16. A

    Circular orbits in Schwarzschild geometry

    Homework Statement Hartle, Gravity, P9.8 A spaceship is moving without power in a circular orbit about a black hole of mass M, with Schwarzschild radius 7M. (a) What is the period as measured by an observer at infinity? (b) What is the period as measured by a clock on the spaceship...
  17. N

    Calculating Proper Time of "A" in Schwarzschild Geometry

    "A" starts a journey from a massive body in Schwarzschild geometry in a radial path and returns back to the starting point while "B" stays at rest. Please explain how to find the proper time of "A".
  18. L

    Solving the Radius of a Collapsing Star in Schwarzschild Geometry

    I have that \left( \frac{dR}{d \tau} \right)^2 = ( 1 - \epsilon)^2 ( \frac{R_{\text{max}}}{R}-1) describes the radius of the surface of a collapsing star in Schwarzschild geometry. I need to show it falls to R=0 in time \tau = \frac{\pi M}{(1-\epsilon)^{3/2}} So far I have rearranged to get...
  19. P

    Heuristic approach to the Schwarzschild geometry - Accident of deeper meaning?

    The Schwarzschild solution can be obtained by using Newton for the weak field. However it turns out that this in fact is the exact solution. Is this coincidence or is there more to it? Opinions? http://arxiv.org/pdf/gr-qc/0309072v3
  20. stevebd1

    Energy in Schwarzschild geometry

    From In Wheeler and Taylor's 'Exploring Black Holes', on pages 3-12, the equation for energy in Schwarzschild geometry for an object in free fall is- \frac{E}{m}=\left(1-\frac{2M}{r}\right)\frac{dt}{d\tau}=1 where \tau is proper time conventionally expressed in Schwarzschild geometry as...
  21. J

    Understanding the 3 coordinate systems for a Schwarzschild geometry

    Hello, There are 3 main coordinate systems for a Schwarzschild geometry : Lemaitre-Rylov (LR), Eddington-Finkelstein (EF), Kruskal-Szekeres (KS). Thanks to my readings, I know thaht KS coordinates are better than EF coordinates and that EF coordinates are better than LR coordinates. But, I...
  22. A

    Solving the Transformation to Eddington-Finkelstein in Schwarzschild Geometry

    Homework Statement I'm having problems seeing how the transformation to Eddington-Finkelstein in the Schwarzschild geometry works. Any help would be great! Homework Equations So we have the Schwarzschild Geometry given by: ds^2 = -(1-2M/r)dt^2 + (1-2M/r)^-^1 dr^2 +...
  23. 2

    Understanding Schwarzschild Geometry: Math & Physics Requirements

    To make a long story short I'm suppose to be learning how to "obtain non-zero curvature components of Schwarzschild geometry". However, I'm not sure what all that entails (tensors? differential geometry?). So any advice on what level of math/physics will be needed would be great!
  24. quasar987

    GR problem - satelite in orbit (Schwarzschild geometry)

    Homework Statement An observer in a rocket is in a circular equatorial orbit arounda planet and the period of the orbit is the same as the period of revolution of the planet. The planet has mass M = 1033kg and radius R = 1000km. The observer sends a signal every 20 seconds according to its...
  25. L

    How much is the Schwarzschild geometry a characteristic feature of GR

    The Rindler geometry and its horizon can be obtained by a simple succession of Poincaré transformations to match the frame of an accelerated observer. By combining this SR result and the equivalence principle it follows that a uniform gravitational field is represented by the Rindler metric and...
  26. L

    Was the Schwarzschild geometry acceptable

    Today, as I guess, there are good indications that black-holes are a reality. But let us go back in time and pretend we are physicists in 1916 or a few years later. Schwarzschild lectures us about its static and spherical solution to the Einstein's equation. The consequence is striking: any...
  27. L

    What Is the Plane Schwarzschild Geometry?

    Dear all, I would like to know about a possible plane Schwarzschild geometry. This would be the analog of a uniform and infinite gravitational field, or a uniform acceleration. I would like to compare it with the solution of the uniformly accelerated motion in SR. Thanks,
  28. A

    Schwarzschild geometry unstable orbit GR question

    Hey folks, working problems in Hartle's GR book and having trouble with this one. Chapter 9 discusses the simplest physically relavent curved geometry, that of Mr. Swarzschild ds^s = -(1 - \frac{2 G M}{r}) dt^2 + (1 - \frac{2 M}{r})^{-1} dr^2 +r^2(d\theta^2 + sin^2\theta d\phi^2) In this...
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