DOCS.
270,
271
JUNEJULY
1911
193
V Ū
/00
F
T\
v
=0
V
p
V
\
dv
v
0
V
/
0
where
(p
is
a
universal function that
is
very
difficult to
determine
analytically.
Your
formula
is produced
if
one
chooses
(p
in
the
following way,
P
A
m
ui
j\
A
i
2
V
V0
1
But in
reality
this will
not obtain;
instead,
frequencies
other than
v0
and

will also
appear.
But
one
should be satisfied if
one can
manage
with
your simple
schemat
ization.[7]
Finally,
let
me
note
that
it would be
of the
greatest
interest
if
the thermal
con
ductivity
of
simple
insulators that
behave
normally
with
regard
to
specific
heat
(e.g., KCl)
would be
investigated
for thermal
conductivity
at
the
lowest
temperatures.
For
I
deduce
from
the
quantum
hypothesis
with
certainty
that
the coefficient
of thermal
conductivity
must drop again
at
the
lowest
temperatures,
that,
in
fact,
it
must
drop exponentially
to
zero.[8]
If
this
does
not
prove
to be the
case,
then the
quantum hypothesis
has
to be
abandoned,
in
my
opinion.
I will
append
this
to
my
latest
paper
as a
supplement
added
in
proof.
The
explanation is
a
little too
lengthy
to be
presented
here.
With
highest regards,
your very
devoted
A.
Einstein
271. To
Lucien
Chavan
[Prague,
56
July
1911][1]
Dear
Mr. Chavan:
About
a
month
ago
Mr.
Zangger
went
to
see
Forrer and
apprised
him
of the
deplorable
state
of
affairs in the
Technical
Department.[2]
It
so
happened
that
a
representative
of
the Bell Co.
was present
who
annoyed
Forrer
very
much
by
his
insolent
conduct.[3]
Also,
a
complaint against Redding
was on
Forrer's
desk;[4]
he
just
has
to
have
a
quarrel
with
somebody.
Forrer
promised
to examine
everything
and to
keep
a
close