Concept explainers
The proof that the Jeans length for the universe at the era of recombination was about
Answer to Problem 37Q
The proof that the that the Jeans length for the universe at the era of recombination was about
Explanation of Solution
Given:
The temperature of the early universe is,
The density of the universe is,
Formula Used:
The expression for Jeans length is given by,
Here,
The expression for volume is given by,
The expression for mass density is given by,
Rewrite the above expression for mass.
Calculation:
The Jeans length is calculated as,
Solve further,
The mass contained in the sphere is calculated as
Solve further,
This value is nearly equal to
Conclusion:
Therefore, it is proved that the Jeans length for the universe at the era of recombination was about
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Chapter 26 Solutions
Universe: Stars And Galaxies
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