1. Number of thermal photons. Show that the number of photons

icon
Related questions
Question
1. Number of thermal photons. Show that the number of photons E<s,) in
equilibrium at temperature t in a cavity of volume V is
N = 2.404n-2V(t/hc)³.
(48)
From (23) the entropy is o =
believed that the total number of photons in the universe is 10$ larger than the
total number of nucleons (protons, neutrons). Because both entropies are of
the order of the respective number of particles (see Eq. 3.76), the photons
provide the dominant contribution to the entropy of the universe, although
the particles dominate the total energy. We believe that the entropy of the
photons is essentially constant, so that the entropy of the universe is approxi-
mately constant with time.
(472 V/45)(t/hc)', whence a/N - 3.602. It is
Transcribed Image Text:1. Number of thermal photons. Show that the number of photons E<s,) in equilibrium at temperature t in a cavity of volume V is N = 2.404n-2V(t/hc)³. (48) From (23) the entropy is o = believed that the total number of photons in the universe is 10$ larger than the total number of nucleons (protons, neutrons). Because both entropies are of the order of the respective number of particles (see Eq. 3.76), the photons provide the dominant contribution to the entropy of the universe, although the particles dominate the total energy. We believe that the entropy of the photons is essentially constant, so that the entropy of the universe is approxi- mately constant with time. (472 V/45)(t/hc)', whence a/N - 3.602. It is
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer