  We present direct measurements of fluctuations in the nucleus of yeast cells.
While prior work has shown these fluctuations to be active and non-thermal in
character, their origin and time dependence are not understood. We show that
the nuclear fluctuations we observe are quantitatively consistent with
uncorrelated, active force fluctuations driving a nuclear medium that is
dominated by an uncondensed DNA solution, for which we perform rheological
measurements on an {\it in vitro} model system under similar conditions to what
is expected in the nucleus.
