Stefan-Boltzmann’s Law
By integrating/summing over frequencies in Plancks radiation law (4.1), one
obtains Stefan-Boltmann’s Law stating the the total radiated energy R(T)
per unit surface area emitted by a black-body is proportional to T
4
:
R(T) = σT4
(4.3)
where σ =
2π
5k
4
15c
2h3 = 5.67 × 10−8 W−1m−2K−4
is Stefan-Boltzmann’s constant.
On the other hand, the classical Rayleigh-Jeans Radiation Law Rν(T) ∼
T ν2 without the cut-off factor, results in an “ultra-violet catastrophy” with
infinite total radiated energy, since ∑n
ν=1 ν
2 ∼ n
3 → ∞ as n → ∞.
Stefan-Boltzmann’s Law fits (reasonably well) to observation, while the
Rayleigh-Jeans Law leads to an absurdity and so must somehow be incorrect.
The Rayleigh-Jeans Law was derived viewing light as electromagnetic waves
governed by Maxwell’s equations, which forced Planck in his “act of despair”
to give up the wave model and replace it by statistics of “quanta” viewing
light as a stream of particles or photons. But the scientific cost of abandoning
the wave model is very high, and we now present an alternative way of
avoiding the catastropheby modifying the wave model by finite precision
computation, instead of resorting to particle statistics.
We shall see that the finite precision computation introduces a highfrequency
cut-off in the spirit of the finite precision computational model