What was the temperature of the universe when a typical CMB photon was no longer able to spontaneously create a proton and antiproton pair? Note that a photon has an energy equal to E hc/λ,the CBR at any point in time has a blackbody spectrum that peaks at λ_peak = (2,900 μm K)/T,and the mass of a single proton is 1.7 × 10⁻²⁷ kg.

Question

Quizplus · Accepted Answer

The Answer of What was the temperature of the universe when a typical CMB photon was no longer able to spontaneously create a proton and antiproton pair? Note that a photon has an energy equal to E hc/λ,the CBR at any point in time has a blackbody spectrum that peaks at λ_peak = (2,900 μm K)/T,and the mass of a single proton is 1.7 × 10⁻²⁷ kg.

What Was the Temperature of the Universe When a Typical