Biased tracers and time evolution

Mirbabayi, Mehrdad; Schmidt, Fabian; Zaldarriaga, Matías

doi:10.1088/1475-7516/2015/07/030

Cited by 188 publications

(290 citation statements)

References 20 publications

Supporting

Mentioning

284

Contrasting

Order By: Relevance

“…IV) however. The equivalence principle guarantees the absence of halo velocity bias at lowest order in derivatives [29]. In other words, at lowest order in derivatives halos move along the trajectories of the matter fluid itself.…”

Section: A Halo Clusteringmentioning

confidence: 91%

“…As argued in Ref. [29], halo velocities are unbiased with respect to matter velocities up to higher derivative terms; that is, the velocity of the effective halo fluid obtained by coarse-graining the halo distribution is given by…”

Section: Matter Velocity Fieldmentioning

confidence: 92%

“…Complete bases for the bias expansion have been described in [29,30]; renormalization of bias operators is described in [31,32]. The fields , O are stochastic fields with zero means which are completely characterized by their moments [ ](M, x, τ )[ ](M , x, τ ) and so on (again, this holds at lowest order in derivatives).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Towards a self-consistent halo model for the nonlinear large-scale structure

Schmidt

2016

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

The halo model is a theoretically and empirically well-motivated framework for predicting the statistics of the nonlinear matter distribution in the Universe. However, current incarnations of the halo model suffer from two major deficiencies: (i) they do not enforce the stress-energy conservation of matter; (ii) they are not guaranteed to recover exact perturbation theory results on large scales. Here, we provide a formulation of the halo model ("EHM ") that remedies both drawbacks in a consistent way, while attempting to maintain the predictivity of the approach. In the formulation presented here, mass and momentum conservation are guaranteed on large scales, and results of perturbation theory and the effective field theory can in principle be matched to any desired order on large scales. We find that a key ingredient in the halo model power spectrum is the halo stochasticity covariance, which has been studied to a much lesser extent than other ingredients such as mass function, bias, and profiles of halos. As written here, this approach still does not describe the transition regime between perturbation theory and halo scales realistically, which is left as an open problem. We also show explicitly that, when implemented consistently, halo model predictions do not depend on any properties of low-mass halos that are smaller than the scales of interest.

show abstract

Section: A Halo Clusteringmentioning

confidence: 91%

Section: Matter Velocity Fieldmentioning

confidence: 92%

See 1 more Smart Citation

Towards a self-consistent halo model for the nonlinear large-scale structure

Schmidt

2016

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

show abstract

“…Include the peak property of proto-halos can be done as described in [57,63] or by a more agnostic effective theory approach [64]. In practice this means that one needs to include considerably more terms in the bias, such that F and Ψ X depend now on δ R , ∂ i δ R , ∂ i ∂ j δ R and the tidal gravitational field ∂ i ∂ j Φ which then demands computing a whole new set of correlators within CLPT.…”

Section: Choosing the Smoothing Scalementioning

confidence: 99%

Gaussian streaming with the truncated Zel’dovich approximation

2016

View full text Add to dashboard Cite

We calculate the dark matter halo correlation function in redshift space using the Gaussian streaming model (GSM). To determine the scale dependent functions entering the streaming model we use local Lagrangian bias together with Convolution Lagrangian perturbation theory (CLPT) which constitutes an approximation to the Post-Zel'dovich approximation. On the basis of N-body simulations we demonstrate that a smoothing of the initial conditions with the Lagrangian radius improves the Zel'dovich approximation and its ability to predict the displacement field of proto-halos. Based on this observation we implement a "truncated" CLPT by smoothing the initial power spectrum and investigate the dependence of the streaming model ingredients on the smoothing scale. We find that the real space correlation functions of halos and their mean pairwise velocity are optimised if the coarse graining scale is chosen to be 1 Mpc/h at z = 0, while the pairwise velocity dispersion is optimised if the smoothing scale is chosen to be the Lagrangian size of the halo. We compare theoretical results for the halo correlation function in redshift space to measurements within the Horizon Run 2 N-body simulation halo catalog. We find that this simple two-filter smoothing procedure in the spirit of the truncated Zel'dovich approximation significantly improves the GSM+CLPT prediction of the redshift space halo correlation function over the whole mass range from large galaxy to galaxy cluster-sized halos.

show abstract

“…These references mainly focussed on the two-point functions, while [18,19] considered the matter bispectrum and [20] looked at non-Gaussian effects. The Lagrangian space formulation of the EFT of LSS has been studied in [21,22] and finally, aspects of bias and baryonic effects have been considered in [23][24][25][26][27][28][29][30].…”

Section: Introductionmentioning

confidence: 99%

Effective field theory of large scale structure at two loops: The apparent scale dependence of the speed of sound

2015

Self Cite

View full text Add to dashboard Cite

We study the Effective Field Theory of Large Scale Structure for cosmic density and momentum fields. We show that the finite part of the two-loop calculation and its counterterms introduce an apparent scale dependence for the leading order parameter c 2 s of the EFT starting at k = 0.1 hMpc −1 . These terms limit the range over which one can trust the one-loop EFT calculation at the 1% level to k < 0.1 hMpc −1 at redshift z = 0. We construct a well motivated one parameter ansatz to fix the relative size of the one-and two-loop counterterms using their high-k sensitivity. Although this one parameter model is a very restrictive choice for the counterterms, it explains the apparent scale dependence of c 2 s seen in simulations. It is also able to capture the scale dependence of the density power spectrum up to k ≈ 0.3 hMpc −1 at the 1% level at redshift z = 0. Considering a simple scheme for the resummation of large scale motions, we find that the two loop calculation reduces the need for this IR-resummation at k < 0.2 hMpc −1 . Finally, we extend our calculation to momentum statistics and show that the same one parameter model can also describe density-momentum and momentum-momentum statistics.

show abstract

Biased tracers and time evolution

Cited by 188 publications

References 20 publications

Towards a self-consistent halo model for the nonlinear large-scale structure

Towards a self-consistent halo model for the nonlinear large-scale structure

Gaussian streaming with the truncated Zel’dovich approximation

Effective field theory of large scale structure at two loops: The apparent scale dependence of the speed of sound

Contact Info

Product

Resources

About