DOC.
596
AUGUST
1918 621
596. From Friedrich Adler
Stein-on-the-Danube,
9 August 1918
Dear
Friend,
Cordial
thanks
for
your
letter, postcard,
and
the
book
by
Weyl.[1]
I have
looked
through
the
book and
it
appears
to
me
to
be
very good
as
an
introduction
to
the mathematical
problems.
However,
he
brushes off
what
seems
to
me
to be
the
main
physical question, namely,
the
time
concept,
just
as
lightly
as
do
other
explanations.
You
will
see
what
I
mean
when
you
read
my paper,
which
was
sent
out to
you
last
week and which
you probably already
received in
the meantime.[2]
In
the
copy
I prepared
for
you,
a
small emendation
is
still
missing, as
I
see
in
retrospect.
Namely,
if
the
value
for
x
from formula
(77b)[3]
is
introduced
into
(48),
the
generally
valid formula for the
“starting
time”
results:[4]
ta
=
X
V
and there
(~Ti~:
71 1
us
applies;
so
this
starting
time is
always only a
function
of
u,
and
the
relation[5]
t'a=ru's
ta
Us
between
the
starting
times
corres[pondingly]
results;
hence
a
dependence
on
7.
When
you emphasize
the limitation
of
theoretical
possibilities
as an
advantage
of
the
theory
of
relativity,
I
think that this limitation
is not
weakened
by
the
proof
of
the
necessity
for
the
assumption
of
a
preferred
reference
system.
But
I
hope
we
shall
understand
each
other
more
quickly
on
all these
questions
when
you
have read
my
work.
For
today I
just
want to
say
that
my
admiration
for
your
achievement
grew
proportionately
as
I penetrated
into
the
problem
and
as
the
immense amount
of
difficulties
you
were
facing
became clearer
to
me.
And
this
admiration
did
not
diminish
in
the
least
by
the
fact
that
it
simultaneously
became
increasingly
clear to
me
that
your
solution
is
an
inadmissible
generalization
of
a
special case.
What
a
pity
that
we
cannot discuss this
question orally,
but
I
hope
I
have worked
it
out
clearly enough
in
the
book.
A
note
was
inside
the
book
by
Weyl
that
you
sent
me,
which
you
had
forgotten
to
remove.
As
you may possibly
be
looking
for
it,
I
am sending
it back to
you
herewith
by
return
post.