192
THEORY OF
LIGHT
PRODUCTION
Doc. 34
ON
THE THEORY OF
LIGHT
PRODUCTION
AND
LIGHT ABSORPTION
by
A.
Einstein
[Annalen
der
Physik 20
(1906):
199-206]
In
a
study published
last
year1
I
showed
that
the
Maxwell theory
of
[2]
electricity
in
conjunction
with
the
theory of
electrons leads
to
results that
contradict the evidence
on
black-body
radiation.
By
a
route
described
in that
study,
I
was
led
to
the
view
that
light
of
frequency
v can
only be absorbed
or
emitted in
quanta of
energy (R/N)ßv,
where
R
denotes
the absolute
constant
of the
gas
equation applied
to
one
gram-molecule,
N
the
number
of
actual molecules
in
one
gram-molecule, ß
the
exponential
coefficient
of
Wien's
(and
Planck's) radiation
formula,
and
v
the
frequency
of the
light
in
question.
This
relationship
was developed
for
a
range
that
corresponds to
the
[3] range
of
validity
of Wien's
radiation formula.
At
that time it
seemed
to
me
that
in
a
certain respect Planck's
theory
of
radiation2
constituted
a
counterpart
to
my
work.
New
considerations,
which
are
being
reported in
§1
of
this
paper, showed
me,
however,
that the theore-
tical foundation
on
which
Mr.
Planck's radiation
theory
is
based
differs
from
the
one
that
would
emerge
from Maxwell's
theory
and
the
theory
of electrons,
precisely because
Planck's
theory makes
implicit
use
of the aforementioned
hypothesis
of light
quanta.
In
§2
of this
paper
I
shall
make
use
of
the
hypothesis
of
light
quanta
to
derive
a
relationship between
the Volta effect
and photoelectric
diffusion.
§1.
Planck's
theory of
radiation
and the light
quanta
In
§1
of
my
paper
cited
above
I
have
shown
that
the
molecular
theory
of
heat
combined
with the
Maxwell
theory
of electricity
and
the
theory of
1A.
Einstein,
Ann. d.
Phys.
17
(1905):
132.
2M.
Planck,
Ann. d.
Phys.
4 (1901):
561.
[1]
[4]