Friedmann Equation demonstration - Liddle

AI Thread Summary
The discussion centers around the Friedmann Equation demonstration in A. Liddle's "Introduction to Modern Cosmology," specifically addressing concerns about equation (3.4) related to the potential energy of a test particle. One participant believes there is a missing factor of 2 in the denominator of this equation, while another participant disagrees, asserting that the equation is correct as presented. The conversation highlights the importance of verifying mathematical details in cosmological equations. Additionally, corrections provided by Liddle on his website are mentioned as a resource for further clarification. The dialogue emphasizes the need for precision in cosmological calculations.
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Are you confortable with the demonstration in page 19 of Introduction to Modern Cosmology - A. Liddle ? My problem is in particular eq. (3.4) when he writes the potential energy of a test particle. I think there is a factor of 2 missing in the denominator.
 
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Equation 3.4 looks OK to me. He posts corrections on:

http://astronomy.sussex.ac.uk/~andrewl/cosbook.html
 
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