Summary: Nuclear PhysicsB237(1984)226-236
GAUGE-INVARIANT COSMOLOGICAL FLUCTUATIONS OF
Physics Department, Brandeis University, Waltham, MA 02254, USA
Mark B. WISE
California Institute of Technology, Pasadena, CA 91125, USA
Received25 July 1983
The gauge-invariantapproach to cosmologicalperturbations introduced by Bardeen is ex-
tended to the case of multiple fluids which are uncoupled, except for gravitationalinteractions.
The most generalscalar,vector,and tensorfluctuationsare considered.The resultingequationsare
applied to fluctuations involving axions and radiation and axions and baryons in the early
There is considerable evidence  that the energy density of the universe contains
a large dark matter component along with the ordinary luminous component we see.
Massive neutrinos , photinos , gravitinos  and axions  have all been
proposed as candidates for the dark matter. The luminous and dark matter appear to