R. D. Joseph  Astronomy 627                    Cosmology              Spring Term 2002

 

Textbook: M. S. Longair, Galaxy Formation, Springer, 1998.

 

Useful references:

 

J. E. Gunn, M. S. Longair, M. J. Rees, Observational Cosmology, Saas-Fee Lectures, 1978.

E. W. Kolb & M. S. Turner, The Early Universe, Addison-Wesley, 1990.

J. V. Narlikar, Introduction to Cosmology, Cambridge Univ Press, 2002.

J. D. North, The Measure of the Universe, Dover paperback reprint 1990 of the original 1965 edition from Oxford Univ Press.

J. A. Peacock, Cosmological Physics, Cambridge Univ Press, 1999.

P. J. E. Peebles, Physical Cosmology, Princeton Univ Press, 1971.

P. J. E. Peebles, The Large-Scale Structure of the Universe, Princeton Univ Press, 1980.

P. J. E. Peebles, Principles of Physical Cosmology, Princeton Univ Press, 1993.

M. Rowan-Robinson, Cosmology, 3rd edn., Oxford Univ Press, 1996.

There are several good articles in the current issue of Annual Reviews of Astronomy and Astrophysics, vol. 39, 2001, as well as in past issues.  Some which are particularly relevant include:

¨     S. E. Carroll, W. H. Press, & E. L. Turner, 1992. “The Cosmological Constant,” Ann. Rev. Astron. Astrophys., 30, 499.

¨     J. V. Narlikar & T. Padmanabhan, “Standard Cosmology and Alternatives: A Critical Appraisal,” Ann. Rev. Astron. Astrophys., 39, 211.

¨     J. V. Narlikar & T. Padmanabhan, “Inflation for Astronomers,” Ann. Rev. Astron. Astrophys., 29, 325.

¨     M. White, D. Scott, & J. Silk, “Anisotropies in the Cosmic Microwave Background,” Ann. Rev. Astron. Astrophys., 32, 319.

 

Course grading scheme.

 

There will be one homework a week, and these will count for about 60% of the total mark.  There will be one mid-term and one final exam, and each will count 20% of the total mark.

 

Style of the course

 

My major aim in the course is that students understand the material we cover.  How much material is covered and to what depth is secondary to a secure level of comprehension. This is a course in astrophysical cosmology in the sense that we are interested in the physics that takes place in the large-scale Universe, and we are not restricting merely to development of the classical world models.  This is one of the most exciting subjects in natural science, a study in which we investigate some of the most profound questions one can ask in physical science.  It is a subject in which the physics of the very small, particle physics at >1015 GeV, is intimately connected with the physics of the largest scales in the Universe.  However, we will not develop GR or quantum field theory but we will attempt to give a physical sense of where ideas from these subjects impinge on cosmology.  I hope to have organized a course which provides a fundamental understanding of cosmological issues for working astronomers.


Course Outline

 

Introduction and historical review

 

1 The observational context

 

The Cosmic Microwave Background Radiation (CMBR)

Hubble expansion

Galaxies

Dark matter

Clustering properties of galaxies and large-scale structure

Peculiar velocities and deviations from isotropic Hubble flow

Light element abundances

 

2 The theory of gravitation

 

Difficulties with Newtonian gravitation

Mach’s Principle

Isotropic curved spaces

Review of Special relativity, 4-vectors, covariant formulation of electrodynamics

The fundamental assumptions of General Relativity (GR)

Outline of the program of GR

The Einstein field equations

 

3 The “standard” cosmological models

 

Cosmological “Principles”

The Robertson-Walker metric

Measurements of distances, luminosities, angular sizes, etc. in the cosmological context

The Friedman models of classical cosmology

Observational tests of the Friedman models

The Anthropic Principle and Dirac's large numbers

 

4 Thermal history of the Universe.

 

Radiation-dominated expansion

The epoch of “recombination”

Fluctuations in the surface of last scattering

 

5 Big-Bang Nucleosynthesis

 

Nuclear statistical equilibrium in the early Universe

Synthesis of the light elements

Measurements of primordial light element abundances

Baryon and lepton asymmetry in the early Universe

 


6 Inflationary cosmology

 

Puzzles of expansion, flatness, horizon

Equation of state for inflation

Inflation scenario

Fluctuation spectrum emerging from the inflationary epoch

Critique of inflationary models

 

7 Galaxy formation

 

Jeans’ instability

Growth of density perturbations in Friedman models

Dissipation processes

Adiabatic and isothermal fluctuations in baryonic matter

Growth of fluctuations and damping processes in non-baryonic matter

Hot dark matter models

Cold dark matter models

Comparison of measured clustering spectra with model predictions

Peculiar velocity fields

 

8 The Post-Recombination Universe

 

8a Fluctuations in the Cosmic Microwave Background Radiation

 

Gravitational, adiabatic, and Doppler perturbations

Multipole expansion of temperature fluctuations

Interpretation of angular structure in the CMBR

Re-heating of the intergalactic gas

Sunyaev-Zeldovich Effect

Observations of CMBR anisotropies

 

8b Evolution of galaxies

 

Non-linear collapse of density perturbations

Press-Schechter description of hierarchical clustering

Source counts for various classes of galaxies

Background radiation due to various classes of galaxies

 

8c Evolution of star formation rates and element abundances

 

Lyman-alpha clouds

Counts of star-forming galaxies out to large redshifts

Cosmic chemical evolution