Related papers: Special Features of Galactic Dynamics
Observations show that early-type galaxies contain a considerable amount of interstellar dust, most of which is believed to exist as a diffusely distributed component. We construct a four-parameter elliptical galaxy model in order to…
We present evidence that all galaxies, of any Hubble type and luminosity, bear the kinematical signature of a mass component distributed differently from the luminous matter. We review and/or derive the DM halo properties of galaxies of…
Galaxies are composed of baryonic stars and gas embedded in dark matter halos. Here I briefly review two aspects of the connection between baryons and their halos. (1) The observed baryon content of galaxies falls short of the cosmic baryon…
The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies have been studied using the Planetary Nebula Spectrograph. The galaxies' velocity dispersion profiles are found to decline with radius; dynamical…
The collapse of non-collisional dark matter and the formation of pancake structures in the Universe are investigated approximately. Collapse is described by a system of ordinary differential equations, in the model of a uniformly rotating,…
In these notes we present a selection of topics, each section approximately amounting to one lecture. We begin with a brief recapitulation of General Relativity, and the Standard Model of Cosmology. This is followed by lectures on important…
This text is a slightly edited version of lecture notes for a course I gave at ETH, during the Winter term 2000-2001, to undergraduate Mathematics and Physics students. Contents: Chapter 1 - Examples of Dynamical Systems Chapter 2 -…
The aim of these Lectures is to provide a brief overview of the subject of asymptotic symmetries of gauge and gravity theories in asymptotically flat spacetimes as background material for celestial holography.
We review progress in understanding the formation of galactic disks in the standard cosmogonic scenario involving gravitational clustering of baryons and dark matter and dissipative collapse of the baryons. This scenario accounts remarkably…
We present the hierarchical structure of the gas and its rapid evolution in the central region of a simulation of the entire Milky Way, run at subparsec resolution. We emphasize the coupling between the kpc-scale dynamics, the molecular…
The discrepancy between the visible mass in galaxies or galaxy clusters, and that inferred from their dynamics is well known. The prevailing solution to this problem is dark matter. Here we show that a different approach, one that conforms…
This thesis aims to review the cosmological mass function problem, both from the theoretical and the observational point of view, and to present a new mass function theory, based on realistic approximations for the dynamics of gravitational…
This paper is the first in a series in which we present the results of an ESO Large Program on the kinematics and internal dynamics of dwarf elliptical galaxies (dEs). We investigate the relations between the parameters that quantify the…
These lectures review certain topological defects and aspects of their cosmology. Unconventional material includes brief descriptions of electroweak defects, the structure of domain walls in non-Abelian theories, and the spectrum of…
A theory is developed for the dynamics of eccentric perturbations $[\propto \exp(\pm i\phi)]$ of a disk galaxy residing in a spherical dark matter halo and including a spherical bulge component. The disk is represented as a large number $N$…
I set the stage for discussion of the stellar populations in interacting galaxies by looking back over the slow development of our understanding of these systems. From early anecdotal collections, to systematic cataloging, and finally to…
In this review, I discuss just three aspects of the stability and evolution of galactic discs. (1) I first review our understanding of the bar instability and how it can be controlled. Disc galaxies in which the orbital speed does not…
Models of structure formation in the universe postulate that matter distributions observed today in galaxy catalogs arise, through a complex non-linear dynamics, by gravitational evolution from a very uniform initial state. Dark matter…
We review recent results on the tidal structures of spiral galaxies. Topics included are general characteristics of tails; kinematics of tidal structures and dark haloes of host galaxies; frequency of tidal distortions at z~1.
Lopsidedness is a common feature in galaxies, both in the distribution of light and in the kinematics. We investigate the kinematics of a model for lopsided galaxies that consists of a disc lying off-centre in a dark halo, and circling…