Clarifying Integral Limits in Equation 4.6: A Scientific Analysis

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Equation 4.6 appears to have incorrect integral limits, as the integral is expressed as ∫_{0}^{∞} B dB, suggesting limits based on z rather than B. The confusion arises from the cancellation of dz in the previous equation, leading to the use of 0 and ∞ instead of the appropriate limits B(z=0) and B(z=∞). This misrepresentation could lead to an infinite result, which is not the case. The discussion highlights a potential oversight in the mathematical notation, indicating a need for clarity in the limits post-cancellation. Overall, the interpretation points to a lack of precision in the presentation of the integral limits.
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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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