Transition Probability | Bransden & Joachain | 4.38 & 4.39 Dimension

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The forum discussion centers on the dimensional analysis of transition probabilities as presented in Bransden & Joachain, specifically equations (4.38) and (4.39). Users identify that while both expressions are intended to be dimensionless, there is a discrepancy due to the dω term in (4.39) not being squared, leading to a potential dimensional inconsistency. The integral forms of these equations are highlighted, with (4.38) representing an amplitude and (4.39) representing the probability, raising questions about their derivation and consistency.

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At page 190 of Bransden & Joachain (see the page from http://books.google.com/books?id=i5...nsden,+Charles+Jean+Joachain&hl=da#PPA190,M1"), there are 2 expressions for the transition probability, (4.38) and it's absolute value squared in (4.39).
Is it just me or are the 2 term dimensionally different? Obviously everything from (4.38) is squared in (4.39) except the d\omega. Hence they can't be the same dimensionally. How can this be right?
 
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I am not sure what the question is, but they are both dimensionless. Probability doesn't have a unit.
 
Cyosis: Yes they are supposed to be dimensionless, but I just looked at the difference between the 2 expressions.

Note that every term from (4.38) appears squared in (4.39) except for the d\omega term which has the same power in both, hence (4.39) is short by a factor of 1/sec.
 
In any case (4.38) is not the probability, it's the amplitude.
 
But it's supposed to be dimensionless like the probability, hence must have the same dimensions.

EDIT:
Ok to make it more clear, then (4.38) has the form

c_b = \int_0^{\infty} f(\omega) \, d\omega

while (4.39) has the form

|c_b|^2 = \int_0^{\infty} |f(\omega)|^2 \, d\omega

which certainly can't be right. What's going on?
 
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That's weird, it certainly does look dimensionally inconsistent, regardless of what cb represents.

I'm assuming ω means what it usually does and has units of s-1.
 

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