Observational Cosmology

Prof. Trevor Ponman


NOTICES

1. The nature of the course

Conventional lectures may be a good way of getting a set of notes into your folder, but they are too passive to be a very good way of communicating real understanding. This course is based on the idea that your grasp of cosmology will be much better if you research and assemble your own set of notes. It will  also help you learn the valuable general skill of being able to research and understand any topic with  minimum assistance. To help you construct your own notes, the course has been divided into 5 units, and I will give guidance as to what material you should cover in each unit, and where you can find the information you need. This Home Page will provide useful guidance and links, and also a place for me to post any notices.  There will be some lectures, but you should not expect all the course  material  to be covered in the lectures.

Each unit will have a lecture at the start, which may be pedagogical (to help you with tricky topics) or to give you an overview or research perspective. In addition, each unit has a discussion /problems class and a set of self-test problems, with solutions, so that you can check your own understanding. Given the nature of the course, it is essential that you should work on it through the term. To encourage 3rd year students to do this, and to give you some more formal feedback on your progress, three of the units will also have associated assessed exercises. Each of these is worth 10% of the course credit. Year 4 students are encouraged to attempt these exercises, which will provide valuable practice, but should not submit answers for assessment. Instead, Year 4 students will tackle a separate, more research-orientated, exercise worth 30%. This involves writing a case for observing time on the Chandra X-ray observatory, to study the dark halos of elliptical galaxies. Advice and links will be provided to support this exercise, however students with little astronomical background are likely to struggle, and are advised against taking this course in Year 4.

The final examination (worth 70%) will be designed to test your understanding. To give you an extra incentive to compile a good, and well-ordered set of notes, you will be able to take your notes  (but not text books) into the examination with you. You should also bring them to all the Obs. Cos. classes, where you may require them.

Your notes

An important aspect of a self-study module such as this is making a good set of notes.  The notes you make should be clear and concise so that you can extract information from them quickly whenever you need it (including in the exam). Before making notes on a topic, try to run quickly through the topic before starting to take notes, so that you can get an overview of what the important points are.  Then go back and make notes on those points. Finally, read through your notes and make sure they are easily comprehensible to you. Your notes for this course should be similar in volume to those for other, more conventional, lecture courses.

Useful advice on notetaking and other study skills can be found in the University's online 4S Programme pages - see especially the sections on  selecting and using written sources , and  getting the most out of lectures.
 As emphasized in these references, good notetaking is a very active process.


 2. Timetable

 

Week/Begin
  Unit
Tuesday 4pm 
 Wednesday 10am
 Friday 12am 
(Arts LR4)
Assignments
1. Sep 29
-
 -
 Lecture - introduction
  
2.  Oct 6
 1
 -
 Surgery Discussion class  
3.  Oct 13
 1
 Surgery Lecture -
unit 2
 -
  1st exercise set
4.  Oct 20
 2
 Surgery
 Surgery Discussion class Yr.4 exercise set
5.  Oct 27
 2
 Surgery
 -
 Lecture - unit 3 
6.  Nov 3
 3
 Surgery Surgery Discussion class 1st exercise due/2nd set
7.  Nov 10
 3
 Surgery
 Surgery
 Lecture - unit 4   
8.  Nov 17
 4
 Surgery
 Surgery
 Discussion class 2nd exercise due*/3rd set
9.  Nov 24
 4
 Surgery
 Surgery
 Lecture - unit 5 
10. Dec 1
 5
 Surgery
 Surgery
 Discussion class  
11. Dec 8
 5
 Surgery Surgery -
 3rd & Yr.4 exercises due

Notes

* Hand-in deadline for the 2nd assessed exercise is now 4pm on Monday Nov.24th.
1. If I have to make any changes to this timetable, I will inform you in the lectures and post a notice at the top of this web page.
2. All surgeries are held in my office (room 236, Physics West). If I'm with someone else, please knock - you have priority during this hour. If nobody appears within 30 min then I will feel entitled to leave, if I need to!
 

3. The units - click here to find detailed course guidance.


4. Reading
The two recommended texts for this course are: These two books are very complementary: Liddle is clear, comprehensible and orientated towards theory, while Rowan-Robinson  provides wider coverage and more observational detail. If you have enough cash, I would  advise buying both books.  Alternatively, you might coordinate with a friend to buy one each, so that you have access to both books. There will be copies of both in the Library, but they may be hard to lay your hands on.

Other useful sources are:

This book is available online here. It is interesting, well-referenced, very much orientated towards observations, and has a lot of interesting detail. However, much of this detail is beyond what is needed for the present course. The book's organisation and order are rather eccentric, and it does not provide a good logical treatment of the basics of cosmology. It also contains many errors, some of which are listed on the accompanying web site. Or look at section QB981 in the library.

If you need something more advanced, try:

Students with little astrophysics background will need to do some background reading to fill gaps in their astronomical knowledge. You will need to familiarise yourself with the basic tools of astronomers, such as angular measurements;  coordinate systems; magnitudes, fluxes and luminosities; optical filter bands (UBV etc.) and colours; stellar classification (OBAFG...), and velocity measurements using redshifts.
 Good sources are first year astronomy texts, such as: or other texts classified under QB43. The course web page for the first year Introduction to Astrophysics course contains information on a variety of basic astronomical topics, in the form of powerpoint slides (as pdf files), which you may find useful. Another useful source is the following chapter (pdf), taken from Bill Press's Introductory Astronomy Course at Harvard.

At a more advanced level, the second year Structure in the Universe course includes an introduction to Cosmology. If you took this course, then you should consult your notes, if not, the relevant section of the course can be downloaded from here.
  

5.  Past exam papers

Previous exam papers:   2003 2004 2005 2006 2007

Note that the format of the exam changed somewhat as of 2004.

6. Links

There are many good cosmology-related web sites. I list below some of the most useful that I have found.

If you do your own search, remember that web pages are not peer reviewed, so you cannot count on them being correct. You may want to check the credentials of web authors (e.g. look in ADS  to see what they have published) to see if they are bona fide astrophysicists, or check whether the website is an academic one (e.g. ends in  .edu, .gov  or .ac.uk). Some excellent advice is available on how to best search the web and assess the contents of what you find, including practical examples.

If you find any other especially informative websites, please email me the URLs and I will add them to the list.

(a) Introductory and general cosmology

Cambridge Cosmology - The homepage of Stephen Hawking's group gives an excellent introductory overview of cosmology
Ned Wright's cosmology tutorial - Goes well beyond the introductory level, and has a "News of the Universe" page for recent developments
A cosmology timeline - From Joseph Tenn of Sonoma State University
WMAP - US Microwave Anisotropy Probe homepage has a useful introductory cosmology section
Patrick Leahy's cosmology site - A variety of useful tutorials, essays and links
The Astronomy Cafe - Excellent and interesting Q&A pages at three levels of astronomical expertise
Scientific American  cosmology special edition (not free, unfortunately)
BBC podcast on Galaxies - from In Our Time (requires MP3 player)


(b) Observational cosmology

Level 5 - A very useful hyperlinked index to many review papers and other resources, from the NASA Extragalactic Database team
Atlas of the Universe - Images showing the appearance of the Universe zooming out from the sun
Groups & clusters of galaxies - A web site giving details of nearby groups and clusters, including Virgo
The multiwavelength Milky Way - Nice presentation of the appearance of our galaxy from radio to gamma ray, with explanations for each band
Astronomical survey projects - Links to survey homepages compiled by AstroWeb
Infrared astronomy - Results from a range of ground and space-based IR instruments


(c) Specific projects

Supernova Cosmology Project - Using high z supernovae to determine the geometry of the Universe
WMAP - US Microwave Anisotropy Probe satellite (COBE follow-up)
Hubble Space Telescope - Nice images with explanations. See also the Hubble Heritage Project.
Dark Matter Searches - The possible candidates for Dark Matter, and how to search for "WIMPs", from the UK Dark Matter Collaboration
Chandra X-ray Observatory - The latest from the major US X-ray observatory
COBE - NASA's Cosmic Background Explorer


(d) Cosmological theory

Ned Wright's cosmology tutorial - Contains a useful introduction and some very nice diagrams
Relativity primers - a variety of useful web pages on Special and General Relativity
Relativity and black holes - from the US National Supercomputer Center, with simulations


(e) Simulating the Universe

Galaxy-galaxy collisions - by Josh Barnes
Collision of the Milky Way and M31 - Simulation of our future by John Dubinski
The Virgo consortium - State-of-the art cosmological simulations
The Hubble Volume project - Simulating a ~3Gpc cube!
The Millennium simulation - A 10 billion particle dark matter simulation with galaxies added
N-body simulations - from the University of Washington

(f) Research publications
ADS - Text and abstracts of published astrophysics papers (searchable) - now also incorporates links to astro-ph
Astro-ph - Astronomy preprint server, very widely used (searchable)

Send comments or suggestions on these pages to  Trevor  Ponman
Last updated  12 January 2009