I'm not sure how it is derived.(adsbygoogle = window.adsbygoogle || []).push({});

Do we follow this order?

1. Temperature at last scattering/recombination/decoupling (3000 K)

2. Measuring the temperature of the CMB (~3K)

3. 3000K/~3K = 1100

4. z=1100

5. t(z)

Or this order?

1. Assume Big Bang and Inflation

2. Determine Volume and Pressure

3. Determine required temperature

4. Temperature at last scattering/recombination/decoupling (3000 K)

5. Measuring the temperature of the CMB (~3K)

6. 3000K/~3K = 1100

7. z=1000

5. t(z)

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# What is the logical setup that determines the epoch of the CMB?

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