Useful Open Source programs:

Maxima: A Computer Algebra System

Stellarium: A Planitary Program.



Lots of Calculations in GR

Here you find all sorts of calculations in general relativity- Riemann tensor, Ricci tensor, Ricci scalar, Einstein tensor et cetera - concerning different metrics: Kahn Penrose, Rindler, Tolman-Bondi, Robertson-Walker, Brinkmann and Schwarzschild. The file is constantly renewed. At the end of each chapter I have added a list of textbooks as a reference, which you might find useful.

Lots of calculations in General Relativity Chapter 2 - The metric Tensor Chapter 3 - Four velocity and Four vectors Chapter 4 - Christoffel symbols, geodesic equations and killing vectors Chapter 5 - Covariant derivative, Lie derivative and Killing's equation Chapter 6 - The Riemann and Ricci tensor Chapter 7 - Cartans' structure equations - a shortcut to the Einstein tensor Chapter 11 - The Schwarzschild Solution Chapter 12 - Black Holes

Textbooks etc.

Choquet-Bruhat, Y: Introduction to General Relativity, Black Holes and Cosmology - Chapter 4 (2016)
McMahon, David: Relativity Demystified (2006)
Hartle, James B: Gravity - An Introduction to Einsteins General relativity (2003)
Wheeler, John Archibald: Geons, Black Holes & Quantum Foam (1998)
d, Inverno, Ray: Introducing Einsteins Relativity (1992)
Kay, David: Tensor Calculus (1988)


Relativity demystified - Errata sheet

Here I present my errata sheet for David McMahons book: Relativity Demystified. If the misprint is marked by an asterix (*) it means that you can find a more thorough presentation in my file ‘lots of calculations’ on this page. The list is not complete, but I will post more on my homepage as I get along (look out for the date). I have made this list entirely on my own, and should you find that I have made something wrong or missed something, which I am bound to, please do not hesitate to contact me:

Errata sheet
Useful links

Gravitational Collapse of Inhomogenous Dust in (2+1) Dimensions:

23.4.2019 -
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