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PROFILE
tur the loue ol her $uhiect
Marina Ratner's energetic path in mathematics
by Julia Angwin
UCKILY FOR HER, THE YEAR
that Marina Ratner applied for
college in the Soviet Union coincided
with Nikita Khrushchev's
denouncement of Stalin. It was 1956,
and the young |ewish girl was trying
to get into Moscow State University-the
Harvard of the USSR. The
doors to the university, normally frozen
shut to )ews, opened a crack that
year during the political thaw . . . and
Marina Ratner slipped in.
The training normally denied to
people of her religion set Ratner on
her course as a mathematician. She is
now a professor at the University of
California, Berkeley, and recently
won a $25,000 award from the National
Academy of Sciences.
The awardrecognizes her "striking
proof" of a fundamentally important
theorem that originated in number
theory and is called the Raghunathan
conjectures. Previous attempts to
prove the conjectures for some particular
cases were very intricate and
provided little insight into what
was going on. Ratner tackled the
proof using a branch of mathematics
called ergodic theory that originated
in the study of thermodynamics.
The roots of the name are the
Greek words erg(eneryyl andhodos
(path). This area of mathematics is
also closely related to probability
theory and statistics. Ratner's
knowledge of ergodic theory helped
her come up with the ideas needed
to prove the conjectures. Her solution
led to further developments in
number theory and the theory of
quadratic forms.
Ratner traces her interest in math
partly to the tutelage of a particular
high school teacher, although as the
child of scientists she had always excelled
in the subject.
"Ireally got a lot out of that one
teacher," she recalled. "He was very
tough and he was very difflcult but
interesting."
About her life as a woman in
mathematics, Ratner said: "I don't
believe when they say that women
have different brains, or that women
arer't treated the same as men or
boys. In my life I did not encounter
any gender discrimination. "
The most important thing for students
is to love their subject, she
said. That is how she won her
teacher's love.
"He would sometimes even ask
me to help in grading the test that he
had given the class," she recalled.
He assigned the students difficult
problems, teaching them to work in
three dimensions as well as in plane
geometry.
"Even students whom he gave a
C, they did very well in college
tests," Ratner recalled.
At Moscow State University, Ratner
honed her mathematical skills.
For four years she studied mostly
math, peppering her curriculum
with only physics classes and the
required Marxism and Communist
Party history courses.
After that, she took a four-year
hiatus, working in a statistics research
group. She also gave birth to
her daughter, Anna.
When Anna was three years old,
her mother went back to school to
get her Ph.D. in mathematics. Russian
students could stay in graduate
school a maximum of three years. If
their doctorate took any longer, they
had to complete it on their own. So,
by 1959, Ratner had her doctorate
and was looking for work.
She taught for a while at a technica1
engineering school, but quickly
decided to emigrate to Israel. She applied
for a visa and was immediately
fired from her fob.
"It was considered unpatriotic and
they called us traitors just because we
wanted to emigrate," she recalled.
Fortunately her visa took only
three months to arrive, and she
quickly joined her relatives in Israel.
After a few years' teaching at the
Hebrew University of |erusalem, she
was hired by the University of Califomia
at Berkeley.
"I liked America from the very
first day, despite the many things
that are not good here," she said. "I
think that not all Americans realize
how great a country it is."
This country is undoubtedly the
richer for the influx of such talented
scholars as Marina Ratner. The
award she received is merely a sign
of what she had aheady given her
adopted land.
o
44 JUI.Y/AUEUST ISS4