370
THE
RADIATION
PROBLEM
a
given space
or
of the
force
of
radiation
pressure
on
a
given
surface
are
much
larger
than
expected from
our
current theory.
We
have
seen
that Planck's radiation
law
can
be
understood if
one uses
the
assumption
that the oscillation
energy
of
frequency
v can occur
only
in
quanta
of
magnitude
hv.
According
to
the aforesaid, it
is
not
sufficient
to
assume
that radiation
can
only be
emitted
and
absorbed in
quanta
of
this
magnitude,
i.e.,
that
we are
dealing
with
a
property
of the emitting
or
[50]
absorbing
matter
only;
considerations
6
and
7
show
that the fluctuations in
the
spatial
distribution
of
the radiation
and
in
the radiation
pressure
also
occur as
if
the radiation consisted of
quanta
of the indicated
magnitude.
Certainly, it
cannot be
asserted that the
quantum
theory
follows
from
Planck's
radiation
law
as a
consequence
and
that
other
interpretations
are
excluded.
However,
one can
assert
indeed
that the
quantum
theory provides
the
simplest
interpretation of the Planck formula.
It
should
be
emphasized
that the considerations
presented would
in the
main
in
no
way
lose their value if
it
should
turn out
that Planck's formula is
not
valid; it is
precisely
that
part of
Planck's formula
which has been
adequately
confirmed
by
experience (the Wien
radiation
law
valid in
the
limit
[51]
for
large
v/T)
which
leads
to
the
theory
of the light
quantum.
9.
The
experimental investigation of
the
consequences
of
the
theory of
light
quanta
is,
in
my
opinion,
one
of
the
most
important
tasks that the
experimental physics
of
today must
solve.
The
results obtained
so
far
can
be
divided into three
groups.
a)
There
are
clues
concerning
the
energy
of
those
elementary processes
that
are
associated with the
absorption
or
emission
of
radiation
of
a
certain
[52]
frequency (Stokes'
rule; velocity of
cathode
rays produced
by
light
or
X-rays;
cathode luminescence,
etc).
To
this
group
also
belongs
the interesting
use
Mr.
Stark
has
made
of the
theory of
light
quanta to
elucidate the peculiar
energy
distribution in the
spectrum
of
a
spectral
line emitted
by
canal
rays.1
The
method
of deduction is
always
as
follows: If
one
elementary
process
produces
another
one,
then the
energy
of the latter is
not larger
than that
of
the former.
On
the other
hand,
the
energy
of
one
of
the
two
elementary
[53]
1J.
Stark,
Phys.
Zeit.
9
(1908): 767
.
Previous Page Next Page

Extracted Text (may have errors)


370
THE
RADIATION
PROBLEM
a
given space
or
of the
force
of
radiation
pressure
on
a
given
surface
are
much
larger
than
expected from
our
current theory.
We
have
seen
that Planck's radiation
law
can
be
understood if
one uses
the
assumption
that the oscillation
energy
of
frequency
v can occur
only
in
quanta
of
magnitude
hv.
According
to
the aforesaid, it
is
not
sufficient
to
assume
that radiation
can
only be
emitted
and
absorbed in
quanta
of
this
magnitude,
i.e.,
that
we are
dealing
with
a
property
of the emitting
or
[50]
absorbing
matter
only;
considerations
6
and
7
show
that the fluctuations in
the
spatial
distribution
of
the radiation
and
in
the radiation
pressure
also
occur as
if
the radiation consisted of
quanta
of the indicated
magnitude.
Certainly, it
cannot be
asserted that the
quantum
theory
follows
from
Planck's
radiation
law
as a
consequence
and
that
other
interpretations
are
excluded.
However,
one can
assert
indeed
that the
quantum
theory provides
the
simplest
interpretation of the Planck formula.
It
should
be
emphasized
that the considerations
presented would
in the
main
in
no
way
lose their value if
it
should
turn out
that Planck's formula is
not
valid; it is
precisely
that
part of
Planck's formula
which has been
adequately
confirmed
by
experience (the Wien
radiation
law
valid in
the
limit
[51]
for
large
v/T)
which
leads
to
the
theory
of the light
quantum.
9.
The
experimental investigation of
the
consequences
of
the
theory of
light
quanta
is,
in
my
opinion,
one
of
the
most
important
tasks that the
experimental physics
of
today must
solve.
The
results obtained
so
far
can
be
divided into three
groups.
a)
There
are
clues
concerning
the
energy
of
those
elementary processes
that
are
associated with the
absorption
or
emission
of
radiation
of
a
certain
[52]
frequency (Stokes'
rule; velocity of
cathode
rays produced
by
light
or
X-rays;
cathode luminescence,
etc).
To
this
group
also
belongs
the interesting
use
Mr.
Stark
has
made
of the
theory of
light
quanta to
elucidate the peculiar
energy
distribution in the
spectrum
of
a
spectral
line emitted
by
canal
rays.1
The
method
of deduction is
always
as
follows: If
one
elementary
process
produces
another
one,
then the
energy
of the latter is
not larger
than that
of
the former.
On
the other
hand,
the
energy
of
one
of
the
two
elementary
[53]
1J.
Stark,
Phys.
Zeit.
9
(1908): 767
.

Help

loading