INTRODUCTION TO VOLUME
3 xxv
Lindemann
suggested
a
modification of
the
theory
of
specific
heats
giving
rise
to
a new
equation
for
temperature
dependence.[44]
The Nernst-Lindemann
formula
fit
the
data
very
effectively even
at
the
lowest
temperatures, as
Einstein had
to admit,
but
he dismissed
their
claim
that
the formula had
any
theoretical basis.
So
far
as
Einstein
was
concerned,
this
new
formula for
speci-
fic
heats
was an
arbitrary
but
effective
way
of
approximating
the
spectrum
of
frequencies
that
really
described
the
oscillations
in the
solid.[45]
He
never
followed
up
this
remark, however,
and there
is
no
indication
that
Einstein
saw any way
of
proceeding
further with the
problem
of
finding
that
frequency
spectrum.[46]
A few
months after his first
visit to
Einstein in March
1910,
Nernst
began
organizing a meeting
where the
widening implications
of
the
quantum hypoth-
esis
could
be
discussed
in
detail
by
a
small
group
of
leading
physicists.[47]
Nernst
persuaded
the
wealthy
Belgian
industrial chemist and
philanthropist,
Ernest
Solvay,
to
provide
funds
for such
a meeting,
and in June
1911
a
letter
of invitation
signed by Solvay
went
to
some twenty-five
of
Europe's
most
eminent
physicists.
The
Solvay
Congress,
as
it
came
to be
called,
met
in
Brussels
from
30
October to
3
November
1911.
Einstein
was one
of
the
partic-
ipants
who
had been
asked
to
prepare
reports
on
particular aspects
of
the
current
problematic
situation in
physics.
These
reports were
to
be circulated
in
advance of the
meeting
and
to
provide
the basis for further discussion.
Einstein's
report
was
to
deal with
specific
heats and the
theory
of
quanta.[48]
In
a
letter
to Nernst,
Einstein
expressed
his
willingness
to
prepare
the
re-
port,
his
delight
with the whole idea of this
meeting,
and his
suspicion
that
Nernst
must
be the
moving spirit
behind
it.[49] Early
in
September
Einstein
was
evidently
hard
at
work
on
his
report
since he
described himself
as
being
"tormented"
by
the
"prattle"
he
had
to
prepare
for the
meeting.[50] By
Octo-
ber he could
hardly
wait for "the witches' Sabbath in Brussels"
to
be
over, so
that
he
could become his
own
master
once again.[51]
[44]Nernst and
Lindemann 1911b.
[45]See
Einstein
1911g
(Doc.
21),
pp. 685-686,
and the Note
Added
in
Proof
on p.
694.
[46]The
problem
of
determining
the
frequency spectrum
for
the normal modes of
a
crystal
lattice
was successfully
attacked
by
two
different methods the
following year. See Debye 1912
and Born and
von
Karman
1912.
[47]See Klein,
M.
1965
and Kuhn
1978,
chap.
9.
[48]Ernest
Solvay
to Einstein, 9
June
1911.
[49]Einstein
to Walther
Nernst, 20
June
1911.
[50]"Wenn
ich
nicht mit der
gleichen
Gründlichkeit
antworte,
so
ist
es,
weil
ich durch meinen
Seich
für den Brüssler
Kongress geplagt
bin." Einstein
to
Michele
Besso,
11 September 1911.
[51]"Nun
aber-wenn
auch noch der Hexensabbat
in Brüssel
vorbei
ist-bin
ich bis
auf
die
Kollegien
wieder mein
eigener
Herr." Einstein
to
Michele
Besso, 21
October
1911.