Clarifying Integral Limits in Equation 4.6: A Scientific Analysis

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SUMMARY

The discussion centers on the interpretation of Equation 4.6 from the paper "http://arxiv.org/pdf/0807.1310v5.pdf," specifically regarding the integral \(\int_{0}^{\infty} B \mathrm{d}B\). The integral's limits are incorrectly presented as values of 0 and infinity for B, rather than the appropriate limits of B(z=0) and B(z=∞) after canceling dz in Equation 4.5. This misrepresentation leads to confusion about the integral's outcome, which should not yield infinity. The analysis concludes that the notation is sloppy and requires clarification.

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http://arxiv.org/pdf/0807.1310v5.pdf

Equation 4.6 strikes me as wrong. The integral is \int_{0}^{\infty} B \mathrm{d}B

The limits of the integral seem to be values of z, but the integral seems to be wrt B. If the limits were values of B, the answer would be ∞. It's clearly not, but I don't understand this.
 
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It looks like he's canceled the dz from numerator and denominator in 4.5 and is left with BdB, but instead of writing the limits as B(z=0) and B(z=inf), they've just written 0 and inf.

The limits would be correct before dz were cancelled, but after, they should be changed. If this is the correct interpretation then I agree it's a little sloppy.
 

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