Peak Patch and WebSky

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[ Note this page is under construction ]

The Peak Patch and WebSky simulations are a highly efficient tool for modelling the large-scale structure of the universe.

The Peak Patch simulations

The Peak Patch simulations model the distribution of dark matter (DM) in the universe by mapping out catalogues of DM halos.

[ add basic steps that pkp takes ]

Peak Patch has been validated by [math]\displaystyle{ N }[/math]-body simulations and has performed favourably compared to other halo-finders.

Peak Patch is additionally a particularly powerful tool for studying beyond-standard-model (BSM) cosmology because the simulation takes as initial conditions either a power spectrum (describing the amount of structures of different sizes that we observe in the universe) or a linear matter density field [math]\displaystyle{ \delta_L(\mathbf{x}) }[/math] (the density of matter in the early universe, before nonlinear effects like gravity have had much chance to operate, leaving a field that is propagated from quantum fluctuations by linear theory only), and because it has built-in support for varying [math]\displaystyle{ \Lambda }[/math]CDM model parameters and primordial non-Gaussianities of a number of forms informed by a range of early-universe physics phenomena. Because it employs only approximate dynamics, complete knowledge of the BSM equations of motion is not required, allowing us to probe wider parameter space.

[ link to George's paper ]

The WebSky simulations

The WebSky simulations produce mock sky maps in a range of observables. Mock sky maps are simulated maps of the sky that are statistically analogous to maps of the sky made by observatories.

[ discuss model ]

[ discuss different response functions ]

[ link to paper ]

Notes

1. WebSky has two pronunciations wɛbskaɪ and wɛbskiː which are understood to exist in superposition [math]\displaystyle{ | \text{WEB} \rangle \otimes \left( \frac{ | \text{sky} \rangle + | \text{skee} \rangle }{ \sqrt{2} } \right) }[/math].