Is the Schwarzschild Metric Solution Correct?

Click For Summary

Discussion Overview

The discussion revolves around the correctness of the Schwarzschild metric solution in general relativity, focusing on variations in the sign conventions used in different references. The scope includes theoretical aspects of the metric and its implications in physics.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • Post 1 presents multiple formulations of the Schwarzschild metric from different references, highlighting discrepancies in the sign of the metric components.
  • Post 2 questions the reliance on Wikipedia as a source and suggests that the differences may stem from sign conventions related to spacelike versus timelike intervals.
  • Post 3 agrees with Post 2, suggesting that the differences in signs may be due to convention and encourages double-checking the signs in the references.
  • Post 4 recommends consulting chapter 7 of Carroll's notes, indicating that the arbitrariness of the sign is addressed there.

Areas of Agreement / Disagreement

Participants express differing views on the significance of the sign differences in the Schwarzschild metric, with some suggesting it may be a matter of convention while others seek a definitive "correct" solution. No consensus is reached regarding which formulation is correct.

Contextual Notes

The discussion does not resolve the implications of the sign differences, nor does it clarify the assumptions underlying the various formulations presented.

Orion1
Messages
961
Reaction score
3


The solution for the Schwarzschild metric is stated from reference 1 as:

[tex]ds^2=- \left(1-\frac{r_s}{r}\right) c^2 dt^2 + \left(1-\frac{r_s}{r}\right)^{-1}dr^2+r^2(d \theta^2 +\sin^2 \theta d \phi^2)[/tex]

The solution for the Schwarzschild metric is stated from references 2 as:

[tex]ds^2 = \left(1 - \frac{r_s}{r} \right) c^2 dt^2 - \left(1 - \frac{r_s}{r} \right)^{-1} dr^2 - r^2 \left(d \theta^2 + \sin^2 \theta d \phi^2 \right)[/tex]

The solution for the Schwarzschild metric is stated from references 3 as:
[tex]ds^2 = \left(1 - \frac{r_s}{r} \right) c^2 dt^2 - \left(1 - \frac{r_s}{r} \right)^{-1} dr^2 - r^2 \left(d \theta^2 - \sin^2 \theta d \phi^2 \right)[/tex][tex]r_s[/tex] - Schwarzschild radius

There is a difference in the sign of the elements between the stated solutions.

Which is the correct solution?
[/Color]
Reference:
http://en.wikipedia.org/wiki/Deriving_the_Schwarzschild_solution
http://en.wikipedia.org/wiki/Tolman-Oppenheimer-Volkoff_equation#_ref-ov_3
http://en.wikipedia.org/wiki/Schwarzschild_metric
 
Last edited:
Physics news on Phys.org
Did you check any references outside of wikipedia?

By the looks, the only difference is the sign convention: is it spacelike or timelike intervals that are represented by real lengths? For what purpose do you want one to be "correct"?
 
Orion1 said:
The solution for the Schwarzschild metric is stated from references 3 as:
[tex]ds^2 = \left(1 - \frac{r_s}{r} \right) c^2 dt^2 - \left(1 - \frac{r_s}{r} \right)^{-1} dr^2 - r^2 \left(d \theta^2 - \sin^2 \theta d \phi^2 \right)[/tex]

Might want to double-check your signs on this one. The third reference looks like it gives the same as the second reference (but distributing the last parenthetical). The differences between the first two are probably just convention, as cesiumfrog said.
 
Why don't you read chapter 7 of Carroll's notes and check for yourself (for one thing, I know that the arbitrariness of the sign is mentioned)
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 43 ·
2
Replies
43
Views
4K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 50 ·
2
Replies
50
Views
4K
  • · Replies 43 ·
2
Replies
43
Views
5K
  • · Replies 19 ·
Replies
19
Views
4K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 8 ·
Replies
8
Views
1K
  • · Replies 8 ·
Replies
8
Views
2K