PPT Slide
Introduction: Clustering at High Redshifts
As we heard in Robert’s and Mauro’s talks, it is now abundantly clear that at least some types of object are at least as strongly clustered at redshifts beyond two as galaxies are today.
This is in strong contrast with the theoretical models, which predict that matter should be very weakly clustered at these redshifts: in most models, even a five sigma overdensity on scales of around 10 co-moving Mpc would only have around 20% more matter than the average.
This seeming contradiction is resolved by biassing: many models predict that biassing will be enormously strong at these redshifts. This occurs if the only galaxies to form lie at very high sigma peaks, which are far more strongly clustered that matter in general.