FOUNDATIONS OF STATISTICAL
PHYSICS
47
The
only
evidence
of
personal
influences
on
Einstein's
early
work
on
statistical
physics
concerns
his
correspondence
with
Michele
Besso from
1903,
and
his conversations with
a
patent-office
colleague, Joseph
Sauter.
Einstein's
correspondence
with Besso
is
discussed
in section III
below,
and in the annotations to
one
of
the
papers.[48]
A
lengthy
discussion
with Sauter
is
mentioned
in a
letter
from
Besso
to Einstein
of
13 June 1952:
Lately
he found
again your papers on thermodynamics
of 26.VI.1902
[Doc.
3]
and
26.I.1903
[Doc. 4].
He remembers
having
discussed
one
of
them at
length
at that
time,
and
having
to
a
certain extent saved what
was
essential in
it,
in
spite
of
a
mistake that he
discovered,
this
in
the face
of
a pessimistic
attitude
on your part;
but he cannot recall which
of
the two it concerned.
Er fand letztlich wieder Deine Arbeiten über
Thermodynamik vom
26.VI.1902
[Doc.
3]
und
26.I.1903
[Doc. 4].
Er
erinnert sich über die eine,
seinerzeit,
lange
diskutiert
zu
haben,
und das Wesentliche davon, trotz
eines
damals
von
ihm entdeckten
Fehlers,
entgegen pessimistischer Einstellung von
Dir,
gewissermassen gerettet zu
haben;
kann
sich aber nicht besinnen welche
von
den beiden
es
betraf.[49]
III
As noted
above,
Einstein's
contributions to the foundations
of
statistical
physics grew
out
of
the Maxwell-Boltzmann tradition in kinetic
theory,
which
was
then also called the
"mo-
lecular
theory
of heat"
("molekulare
Wärmetheorie"),
more specifically,
the
aspect
of
the tradition that
emphasizes
the
general
statistical foundations
of
thermodynamics.
Ein-
stein's
aim
was
to derive the basic
concepts
and laws
of
thermodynamics
from mechanics
and the
probability
calculus. In
doing
so,
Einstein
improved upon
Boltzmann's
arguments
in several
important
respects,
so
that his three
papers on
the
subject
form
a
bridge, parallel
to that in Gibbs
1902,
between
Boltzmann's
work and the modern
approach
to statistical
mechanics.[50]
Among
the features that
distinguish
Einstein's
approach
from
Boltzmann's
are: (1)
his
attempt
at
generality-he tried
to
proceed
with
a
minimum
of
assumptions
about the nature
of
the
systems
under
consideration;
(2)
his
conception
of
what needs to
be derived from these
assumptions-not
only
the second law
of
thermodynamics,
but also
pp.
44 and
46).
See also Einstein
1915a,
pp.
260-261, and the editorial
note,
"Einstein
on
Brownian Motion,"
p.
218.
[48]
See Einstein 1903
(Doc.
4),
notes
4,
6,
and 7.
[49]
Einstein
replied on
13
July
1952 that he
recalled
many
discussions with Sauter about the
papers,
but could not remember the details. Sau-
ter
himself
described this
episode
in
a
radio
broadcast in
1955,
in which he recalled discuss-
ing
Einstein's
early papers during
walks home
with Einstein
after work at the
patent
office
(for
the
text
of
this
talk,
see
Flückiger
1974,
pp.
155-156).
An
error
that
may
be the
one
discov-
ered
by
Sauter
is discussed in Einstein 1903
(Doc.
4), note 7.
[50]
Another
important
transitional work
is
Ehrenfest
and
Ehrenfest 1911. Two
of
the earli-
est texts to
incorporate
the modern statistical
point
of
view
are
Wassmuth 1915 and
Hertz,
P.
1916.