Garth Antony Barber wrote:Is the CMB contaminated with a local signal that affects the low l mode data?
If so what would this do to the standard concordant infinite and almost flat model?
I don't think any serious observer or theorist really claims that the concordance model is infinite: the concordance model is, de facto, only some extremely tiny part of the whole Universe; this tiny part contains the observable sphere and a bit outside of it. The concordance model makes no serious claims about global cosmological parameters (except by politically correct invited speakers who incorrectly use the adjective
global ;).
so again perhaps talk the "age of precision cosmology" is a little premature!
I disagree. If it is confirmed that the Universe has a Poincare dodecahedral space (PDS) global geometry - see
astro-ph/0310253 +
astro-ph/0402608 - then \Omega_m \approx 0.3, \Omega_\Lambda \approx 0.7, H_0 \approx 70 km/s/Mpc will still remain an extremely precise estimate of the local cosmological parameters. Dropping from factors of 2-3 uncertainty to uncertainties of 10% is definitely becoming precise. Of course, people in favour of simplicity might prefer
precise cosmology instead of
precision cosmology. After all
precise is a perfectly good adjective. (If we really want to get into post-modernist obscurationism, why not
precisionisational cosmology? Doesn't that sound high-tech and impressive?)
Anyway, you might want to read some background papers - apart from those above, you might want to start from my rather compact review paper with the basics presented rather simply:
astro-ph/0010185 and then go back into the older reviews if you want more depth.
The most recent workshop/conference on global cosmological parameter estimation was held at the Observatoire de Paris-Meudon in March 2005:
http://cosmo.torun.pl/cgi-bin/twiki/vie ... n2005March
Not many people have linked to their papers, but you have the names of many of the most active people in the field and looking through arXiv you should be able to find most of their recent work.
The work from my own group
astro-ph/0402608 has GPL software associated so you should be able to check our analysis in an afternoon using the original data and maybe think of the next step...
In any case, the Copi et al. work definitely motivates continued work on cosmic topology... :)