This article describes how one can use worksheets to guide undergraduate students through the process of finding solutions to specific cases of the Einstein equation of general relativity. The worksheets provide expressions for a metric's Christoffel symbols and Ricci tensor components for fairly general metrics. Students can use a worksheet to adapt these expressions to specific cases where symmetry or other considerations constrain the metric components' dependencies, and then use the worksheet's results to reduce the Einstein equation to a set of simpler differential equations that they can solve. This article illustrates the process for both a diagonal metric and a metric with one off-diagonal element.
References
1.
N.
Christensen
and T.
Moore
, “Teaching general relativity to undergraduates
,” Phys. Today
65
(6
), 41
–47
(2012
).2.
3.
E. F.
Taylor
and J. A.
Wheeler
, Exploring Black Holes: Introduction to General Relativity
(Addison Wesley Longman
, San Francisco
, 2000
).4.
5.
B. F.
Schutz
, A First Course in General Relativity
, 2nd ed. (Cambridge U.P.
, New York
, 2009
).6.
R. J. A.
Lambourne
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, New York
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).7.
T. A.
Moore
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).8.
See the links under “Curvature and the Einstein Equation” on the website <http://web.physics.ucsb.edu/~gravitybook/mathematica.html>.
9.
See, for example, the computer tools “GRTensor II” (<http://grtensor.phy.queensu.ca>), “Maxima” (<http://maxima.sourceforge.net>), or “Ricci” (<http://www.math.washington.edu/~lee/Ricci/>). See also the list at <https://en.wikipedia.org/wiki/Tensor_software>, though this may not be up to date.
10.
One can find a variety of general relativity simulation programs (as well as other resources) at <http://www.compadre.org/relativity/search/search.cfm?gs=1374&SS=1384&b=1>.
11.
Programs for simulating orbits around black holes and the effective potential energy for objects falling in Kerr spacetime are available at <http://pages.pomona.edu/~tmoore/grw/resources.html>.
12.
W.
Rindler
, Relativity: Special, General, and Cosmological
, 2nd ed. (Oxford U.P.
, Oxford
, 2006
), pp. 419
–421
. Note that although Rindler outlines a method for tabulating Ricci tensor components, he does not explicitly provide the tabulation.13.
See supplementary material at http://dx.doi.org/10.1119/1.4939908, which includes PDF versions of the Diagonal Metric Worksheet and the Off-Diagonal Metric Worksheet, the Xojo source code, and a PDF listing of the source code. To run the computer code, download the Xojo IDE (free) from <http://xojo.com>. This program extensively uses a Xojo feature called “operator overloading,” which allows for the definition of what the +, −, and operators do when they appear between variables pointing to instances of the Expression class. Please note that the program's output still required quite a bit of human post-processing to yield the Off-Diagonal Metric Worksheet. Also note that the program uses “G” where this paper and the worksheet use “H” (which we substituted in the post-processing stage because “G” could easily be confused with the universal gravitational constant).
14.
For a somewhat more detailed argument for this metric, see
R. P.
Gruber
et al, “The impossibility of a simple derivation of the Schwarzschild metric
,” Am. J. Phys.
56
, 265
–269
(1988
).15.
For example, Ref. 12, p. 230;
M. P.
Hobson
, G.
Efstathiou
, and A. N.
Lasenby
, General Relativity: An Introduction for Physicists
(Cambridge U.P.
, Cambridge
, 2006
), p. 201
;16.
Ref. 7, pp. 267–268.
17.
Ref. 7, problem P23.1 (page 276).
18.
Ref. 7, problem P23.6 (page 278).
19.
Ref. 7, pp. 292–302, 306.
20.
Ref. 7, pp. 376–378.
21.
Ref. 7, p. 271ff.
22.
Ref. 3, pp. B-4, B-12 through B-15.
23.
Ref. 7, pp. 180–182.
26.
Ref. 15 (Hobson et al.), p. 256.
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2016
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