"The tide is turning in large scale structure"

Abstract: Tidal effects have long been known to influence dark matter halo formation.  Tidal effects on halo clustering are more subtle, but they do matter for precision cosmology.   I'll describe recent work showing there is, in fact, a strong correlation between the tidal field and galaxy clustering strength in the SDSS.  However, most of this observed galaxy-tidal field correlation is inherited from that for the host halos:  how galaxies populate halos is determined primarily by halo mass than by tidal environment.  The methods used here allow one to produce sub-samples with a wide range of clustering strengths from the same underlying survey, so they potentially increase the reach of precision studies of primordial non-gaussianity and redshift space distortions.  I will also discuss recent insights into another precision probe:  the distance scale inferred from the baryon acoustic oscillation signal in galaxy surveys.