Deep redshift topological lensing: strategies for the T-3 candidate

作者：Roukema Boudewijn F^*; France Martin J; Kazimierczak Tomasz A; Buchert Thomas

来源：Monthly Notices of the Royal Astronomical Society, 2014, 437(2): 1096-1108.

DOI：10.1093/mnras/stt1885

• galaxies: high-redshift
• cosmological parameters
• cosmology: observations
• distance scale

The 3-torus (T-3) Friedmann-Lemaitre-Robertson-Walker model better fits the nearly zero large-scale two-point auto-correlation of the Wilkinson Microwave Anisotropy Probe (WMAP) cosmic microwave background sky maps than the infinite flat model. The T-3 model's parameters, recently found using an optimal cross-correlation method on WMAP data, imply approximately equal-redshift topological lensing at redshifts z similar to 6, the redshift range of the upcoming generation of new instruments and telescopes. We investigate observational strategies that can reject the T-3 solution for a given region of parameter space of physical assumptions, or provide good candidate topologically lensed galaxy pairs for detailed spectroscopic followup. T-3 holonomies are applied to (i) existing z similar to 6 observations and (ii) simulated observations, creating multiply connected catalogues. Corresponding simply connected catalogues are generated. The simulated observational strategies are motivated by the matched discs principle. Each catalogue is analysed using a successive filter method and collecting matched quadruples. Quadruple statistics between the multiply and simply connected catalogues are compared. The expected rejection of the hypothesis, or detection of candidate topologically lensed galaxies, is possible at a significance of 5 per cent for a pair of T-3 axis-centred northern and southern surveys if photometric redshift accuracy is sigma(z(phot)) less than or similar to 0.01 for a pair of nearly complete 100 deg(2) surveys with a total of greater than or similar to 500 galaxies over 4.3 < z < 6.6, or for a pair of 196 deg(2) surveys with greater than or similar to 400 galaxies and sigma(z(phot)) less than or similar to 0.02 over 4 < z < 7. Dropping the maximum time interval in a pair from Delta t = 1 h(-1) Gyr to Delta t = 0.1 h(-1) Gyr requires sigma(z(phot)) less than or similar to 0.005 or sigma(z(phot)) less than or similar to 0.01, respectively. Millions of z similar to 6 galaxies will be observed over fields of these sizes during the coming decades, implying much stronger constraints. The question is not if the hypothesis will be rejected or confirmed, it is when.

• 出版日期2014-1