The energy per unit area per unit time per unit wavelength interval emitted by a blackbody at a temperature T is given by

At a specific temperature, the total power radiated per unit area of the blackbody is equal to the area under the corresponding I_λ versus λ curve. Use this to derive the Stefan€“Boltzmann Law.

Use the fact that

where the gamma function is given by Γ(n + 1) = n! and the Riemann zeta function for n = 3 is

2he? | hc I= 1 ekT hc AkgT