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P. de Bernardis, S. Masi , G. Moreno Dipartimento di Fisica,
Universita' "La Sapienza" 00184 Roma Italy ABSTRACT. Anisotropy
measurement techniques and results are reviewed, with special
attention given to experimental problems. The cosmological
relevance of the dipole anisotropy, the only anisotropy truly
detected in the Cosmic Background Radiation, is discussed. 1.
INTRODUCTION Anisotropy of the Cosmic Background Radiation at 2.7 K
(CBR hereafter) is a cosmological topic with a wide range of
applications. In order to define anisotropy let us consider fig. 1
a, where the celestial sphere is shown with two beams A and B, with
beamwidth 0 and angular separation e. We define the anisotropy of
CBR at angular scale e in terms of the difference i'2,1 between the
CBR flux I(ex,u) measured in the two beams. At small angular scales
(e ) a "stochastic" approach is preferred, and the anisotropy is
defined as .cJ I = GBP (1) I e where the brackets indicate averages
over the whole celestial sphere. At large angular scales e>l a
deterministic approach is preferred, and the CBR flux I(ex, S) is
expressed as a sum of spherical harmonics (2) I (ex, S) = I ~ aIm Y
(ex, S) lm I,m The alm coefficients give the dipole, quadrupole and
higher order components of the anisotropy. 257 P. Galeotti and D.
N. Schramm (eds.), Gauge Theory and the Early Universe, 257-282.
Supernovae are among the most exciting things occurring in the
universe. Much recent research has concentrated on phenomena
related to supernovae. For example, the origin of the cosmic rays
and the origin of the bulk of the heavy elements seem to be closely
associated with the phenomenon of supernovae. With the discovery of
the pulsar in the Crab, it seemed clear that supernovae were also
intimately as sociated with the formation of neutron stars and
perhaps even black holes. The purpose of the conference, of which
this volume contains the proceedings, was to bring together the
leaders of supernova re search, each of whom has concentrated on
different aspects of the problem, to try to form a coherent picture
both observationally and theoretically of our current understanding
of supernovae. In so doing, key invited talks were presented on the
light curves of super novae, both observationally and
theoretically; on the possible uses of supernovae, for example in
determination of the Hubble Constant; on the formation and
evolution of supernova remnants, again both ob servationally and
theoretically. The possibility that supernovae might explain
quasars was also presented. A review of the current status of
statistics of supernovae was presented, giving the rate at which
they go off and the implications with regard to what mass stars are
the progenitors for supernovae. Again, this was presented both from
the observational point of view and from the theoretical stellar
evolution point of view."
The second Erice course in the school of Particle-Astrophysics was
held in May, 1988. The topic choosen was Dark Matter. This is one
of the most exciting top ics at the interface of particle physics
and astrophysics. It is developing rapidly now due to a coming
together not only of the theoretical concepts from the early
universe with the theoretical concepts of galaxy formation, but
also the coming to gether of the theorists, experimentalists and
observers. It is with Dark Matter, the combined interrelated topics
of galaxy formation and the generation of large scale structure
that we see a confrontation of the exotic ideas from the early
universe, such as phase transitions and unification, coming face to
face with the realities of traditional observational cosmology.
These realities have recently been heightened by the tremendous
number of new observations, demonstrating that large scale
structure of the universe is far more complex than anybody had
suspected. In particular, we now see large scale foam, apparent
large scale velocity fields, indicating devations from the Hubble
flow, large scales of the order 100 Mpc, and galaxy formation
occurring at high red shifts much greater than unity. We also see
an apparent correlation of clusters of galaxies that may even
exceed the c- relation of galaxies despite their being on much
larger scales with lower average densities."
This volwne is the proceedings of the third school in particle
astrophysics that Schramm and Galeotti have organized at Erice. The
focus of thirs third school was the Generation of Cosmological
Large-Scale Structure. It was held in November of 1996. The fIrst
school in the series was on "Gauge Theory and the Early Universe"
in May 1986, the second was on "Dark Matter in the Universe" in May
1988. All three schools have been successful under the auspices of
the NATO Advanced Study Institute. This volume is thus the third in
the series of the proceedings of these schools. The choice of the
topic for this third school was natural, since the problem of
generating a large-scale structure has become the most pressing
problem in cosmology today. In particular, it is this generation of
structure that is the interface between astronomical observations
and particle models for the early universe. To date, all models for
generating structures inevitably require new fundamental physics
beyond the standard, SU x SU X U , model of high energy physics.
The 3 2 I seeds for generating structures usually invoke
unifIcation physics, and the matter needed to clump and form them
seems to require particle properties that have not been seen in
laboratories to date.
The second Erice course in the school of Particle-Astrophysics was
held in May, 1988. The topic choosen was Dark Matter. This is one
of the most exciting top ics at the interface of particle physics
and astrophysics. It is developing rapidly now due to a coming
together not only of the theoretical concepts from the early
universe with the theoretical concepts of galaxy formation, but
also the coming to gether of the theorists, experimentalists and
observers. It is with Dark Matter, the combined interrelated topics
of galaxy formation and the generation of large scale structure
that we see a confrontation of the exotic ideas from the early
universe, such as phase transitions and unification, coming face to
face with the realities of traditional observational cosmology.
These realities have recently been heightened by the tremendous
number of new observations, demonstrating that large scale
structure of the universe is far more complex than anybody had
suspected. In particular, we now see large scale foam, apparent
large scale velocity fields, indicating devations from the Hubble
flow, large scales of the order 100 Mpc, and galaxy formation
occurring at high red shifts much greater than unity. We also see
an apparent correlation of clusters of galaxies that may even
exceed the c- relation of galaxies despite their being on much
larger scales with lower average densities."
Supernovae are among the most exciting things occurring in the
universe. Much recent research has concentrated on phenomena
related to supernovae. For example, the origin of the cosmic rays
and the origin of the bulk of the heavy elements seem to be closely
associated with the phenomenon of supernovae. With the discovery of
the pulsar in the Crab, it seemed clear that supernovae were also
intimately as sociated with the formation of neutron stars and
perhaps even black holes. The purpose of the conference, of which
this volume contains the proceedings, was to bring together the
leaders of supernova re search, each of whom has concentrated on
different aspects of the problem, to try to form a coherent picture
both observationally and theoretically of our current understanding
of supernovae. In so doing, key invited talks were presented on the
light curves of super novae, both observationally and
theoretically; on the possible uses of supernovae, for example in
determination of the Hubble Constant; on the formation and
evolution of supernova remnants, again both ob servationally and
theoretically. The possibility that supernovae might explain
quasars was also presented. A review of the current status of
statistics of supernovae was presented, giving the rate at which
they go off and the implications with regard to what mass stars are
the progenitors for supernovae. Again, this was presented both from
the observational point of view and from the theoretical stellar
evolution point of view."
This volwne is the proceedings of the third school in particle
astrophysics that Schramm and Galeotti have organized at Erice. The
focus of thirs third school was the Generation of Cosmological
Large-Scale Structure. It was held in November of 1996. The fIrst
school in the series was on "Gauge Theory and the Early Universe"
in May 1986, the second was on "Dark Matter in the Universe" in May
1988. All three schools have been successful under the auspices of
the NATO Advanced Study Institute. This volume is thus the third in
the series of the proceedings of these schools. The choice of the
topic for this third school was natural, since the problem of
generating a large-scale structure has become the most pressing
problem in cosmology today. In particular, it is this generation of
structure that is the interface between astronomical observations
and particle models for the early universe. To date, all models for
generating structures inevitably require new fundamental physics
beyond the standard, SU x SU X U , model of high energy physics.
The 3 2 I seeds for generating structures usually invoke
unifIcation physics, and the matter needed to clump and form them
seems to require particle properties that have not been seen in
laboratories to date.
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