Integrating Gullstrand-Plainleve Coordinates in Kerr Metric

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SUMMARY

The discussion focuses on integrating Gullstrand-Plainleve coordinates within the Kerr metric framework. The integral presented is defined as \delta=a^2sin(2\theta)\int_r^{+\infty} \frac{v\Omega}{\varpi^2}dr, where \Omega and \varpi^2 are specified in terms of the Kerr parameters. The user expresses difficulty in understanding the integral's limits and the implications of using an online integral calculator, specifically referencing Wolfram's integral tool. The results obtained from the calculator raise questions about the accuracy and completeness of the integration process.

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stevebd1
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I'm looking at Gullstrand-plainleve coordinates in Kerr metric. While on the whole, it seems pretty straight forward, I found the integral aspect a little inaccessible. I've had a look at various web pages regarding integrals but to be honest, I don't know where to start with the following. Any insight would be appreciated.

[tex]\delta=a^2sin(2\theta)\int_r^{+\infty} \frac{v\Omega}{\varpi^2}dr[/tex]

where

[tex]\Omega=\frac{2Mar}{\rho^2(r^2+a^2)+2Ma^2rsin^2\theta}[/tex]

[tex]\varpi^2=r^2+a^2+\frac{2Mra^2}{\rho^2}sin^2\theta[/tex]

[tex]v=\frac{\sqrt{2Mr(r^2+a^2)}}{\rho^2}[/tex]

[tex]\rho^2=r^2+a^2cos^2\theta[/tex]
 
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I used an online integral calculator (replacing r with x) which produced the following results-

http://www.majhost.com/gallery/stevebd/science/msp22530435753657184888_189.gif

Does this look right? (unfortunately it didn't have the means to incorporate the limits of r and +∞. What impact would that have on the results?).

online integral calculator-
http://integrals.wolfram.com/index.jsp
 
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