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Question about deriving the amount of pressure due to an element of momentum space in cosmology (Baumann Cosmology Book Eq. 3.10)
In Daniel Baumann's cosmology book Eq. (3.10) and cosmology lecture notes Eq. (3.2.18) he states that the pressure in the early universe can be defined as
$$P=\frac g{(2\pi)^3}\int d^3 p\ f(p)\times\...
- 394
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2
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What is the theoretical value of this phase space invariant?
So I wanted know how to theoretically calculate this phase space invariant (equation $3.31a$ )$R$ in our universe (FLRW metric) during the cosmological nucleosysthesis:
$$R = \int_{p} \frac{\mathcal{...
- 1,389
1
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2
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Kolb and Turner's expresion for number density Eqn. (3.46) and pressure in Eqn. (3.48)
Having defined the phase space distribution function $f(\textbf{r},\textbf{p},t)$ in $\mu-$space, one can express the information that there are $N$ particles in the volume $V$ through the condition \...
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