INTRODUCTION TO VOLUME
3
xxi
approach
had also
come
to
nothing.[25]
Einstein had been
ready
to
give
up
some
aspects
of
field
theory, light quanta,
and
even
energy conservation,
but
none
of
these
desperate measures
led to
a
solution.
Einstein's intense
efforts to
grasp
the real
essence
of
the
light
quanta he
had
introduced in
1905
came
to
a
halt, at
least
temporarily,
in
May
1911.
He
communicated
to Besso
his decision
to
give
up
the
quest.[26]
"I
no
longer
ask
whether these
light
quanta
really
exist. I
am
also
no
longer trying
to construct
them because
I
now
know
that
my
brain
is
incapable
of
prevailing
this
way."
This did
not
mean,
however,
that
he
had
given
up
his
studies of the
implica-
tions of
quanta.
His
next sentence
read: "But
I
am
thoroughly searching
out
the
consequences,
as
carefully
as
possible,
in order
to be
informed about the
domain in which this
concept can
be
applied."
Einstein had
already
been
pursuing
this kind of
investigation
for
some
time.
IV
Remarkably
little
experimental
evidence in
support
of
the
consequences
of
the
light
quantum
hypothesis
had accumulated
by
1910.
Experiments on
the
photoelectric
effect
had
not
yet
produced unequivocal proof
for the
validity
of
Einstein's
equation.[27]
Although
Einstein had
suggested
in
1905
that
photo-
chemical
processes
should
provide
a
testing ground
for the
light quantum
hypothesis,
in
1909
he
thought
that
such
processes
were
not well
suited
to test
his
ideas because
they
seemed
to
show the
presence
of
a
threshold for
ex-
citation.[28]
But
significant support
for
quanta
suddenly
arrived from
an un-
expected quarter.
In March
1910
Einstein
received
a
visitor from
Berlin-
Walther Nernst-an
important
visitor with
important
news.
Nernst
was
Pro-
fessor of
Physical Chemistry,
a
distinguished
researcher who
had
recently
formulated
a new
heat theorem that would
acquire
the
status
of
a
third law of
thermodynamics.
He
was
also
a
force to
be reckoned with in German
sci-
ence.[29]
To
provide
evidence for his
thermodynamic theory
and
to
explore
its
implications,
Nernst had mounted
a
major
research
program
in
his
laboratory
[25]Einstein
to
Jakob
Laub,
11
November
1910.
For
a
later
comment
on
this
issue,
see
Einstein
1914 (Doc.
26),
pp.
347-348.
[26]"Ob
diese
Quanten
wirklich
existieren,
das
frage
ich nicht mehr. Ich suche
sie
auch nicht
mehr
zu
konstruieren, weil
ich
nun weiss,
dass mein Gehirn
so
nicht
durchzudringen vermag.
Aber ich suche
möglichst sorgfältig
die
Konsequenzen ab,
um
über den Bereich der Anwend-
barkeit dieser
Vorstellung
unterrichtet
zu
werden."
Einstein
to
Michele
Besso, 13 May
1911.
[27]Einstein
to
Arnold
Sommerfeld, July 1910. See
also
Stuewer 1970
and
Wheaton 1978.
[28]Einstein
to
Michele
Besso, 17
November
1909.
[29]For
Nernst
see
Mendelssohn
1973,
Hiebert
1978, 1983,
and Barkan
1990.