Question

In the early universe, free electrons and nuclei combined toform nuetral hydrogen and helium when the temperature dropped toapproximately 3,000K. Nuetral matter scatters radiation much lessthan charged particles do; therefore, the then-existing blackbodyradiation could subsequently expand freely, uncoupled to matter (togood approximation). By what factor has the "colume of theuniverse" increased since the ionization in space dropped toessentially zero?

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