We recently showed that postulated ultracompact minihalos with a steep density profile do not form in realistic simulations enhanced initial perturbations. In this paper we assume small fraction of the dark matter consists primordial black holes (PBHs) and simulate formation structures around them. find scenario halos profiles form, consistent theoretical predictions. If rest weakly interacting massive particles (WIMPs), also show WIMPs dense innermost part these would annihilate produce...

The detection of primordial gravitational waves, or tensor perturbations, would be regarded as compelling evidence for inflation. canonical measure this is the ratio to scalar r. For single-field slow-roll models inflation with small field excursions, Lyth bound dictates that if evolution parameter epsilon monotonic, tensor-to-scalar must below observationally detectable levels. We describe how non-monotonic can evade and generate large r, even excursions. This has consequences power...

The study of the interesting cosmological properties voids in Universe depends on efficient and robust identification such galaxy redshift surveys. Recently, Sutter et al. (2012) have published a public catalogue Sloan Digital Sky Survey Data Release 7 main luminous red samples, using void-finding algorithm ZOBOV, which is based watershed transform. We examine this show that it suffers from several problems inconsistencies, including some extremely overdense regions as voids. As result,...

In simple inflationary cosmological scenarios, the near-exponential growth can be followed by a long period in which Universe is dominated oscillating inflaton condensate. The condensate initially almost homogeneous, but perturbations grow gravitationally, eventually fragmenting if it not disrupted more quickly resonance or prompt reheating. We show that gravitational fragmentation of well-described Schrödinger-Poisson equations and use numerical solutions to large overdensities form after...

A crucial diagnostic of the \Lambda CDM cosmological model is integrated Sachs-Wolfe (ISW) effect large-scale structure on cosmic microwave background (CMB). The ISW imprint superstructures size \sim100\;h^{-1} Mpc at redshift $z\sim0.5$ has been detected with $>4\sigma$ significance, however it noted that signal much larger than expected. We revisit calculation using linear theory predictions in cosmology for number density and their radial profile, take possible selection effects into...

Multiple inflation is a model based on N=1 supergravity wherein there are sudden changes in the mass of inflaton because it couples to 'flat direction' scalar fields which undergo symmetry breaking phase transitions as universe cools. The resulting brief violations slow-roll evolution generate non-gaussian signal we find be oscillatory and yielding f_NL ~ 5-20. This potentially detectable by e.g. Planck but would require new bispectrum estimators do so. We also derive model-independent...

The statistical study of voids in the matter distribution promises to be an important tool for precision cosmology, but there are known discrepancies between theoretical models and actually found large simulations or galaxy surveys. empirical properties observed also not well understood. In this paper, we N-body simulation, using ZOBOV watershed algorithm. As other studies, use sets subsampled dark particles as tracers identify voids, full-resolution simulation output measure densities at...

We perform three-dimensional simulations of structure formation in the early Universe, when boosting primordial power spectrum on approximately kpc scales. demonstrate that our are capable producing power-law profiles close to steep $ρ\propto r^{-9/4}$ halo commonly assumed be a good approximation ultracompact minihalos (UCMHs). However, we show for more realistic initial conditions which halos neither perfectly symmetric nor isolated, profile is disrupted and find Navarro-Frenk-White better...

A detection of the stacked integrated Sachs-Wolfe (ISW) signal in CMB rare superstructures identified SDSS Luminous Red Galaxy catalogue has been reported at very high statistical significance. The magnitude observed previously argued to be more than 3σ larger theoretical ΛCDM expectation. However, this calculation was made linear approximation, and relied on assumptions that may potentially have caused expectation underestimated. Here we update model compare it with an analysis ISW maps...

The discovery of a void size $\sim200\;h^{-1}$Mpc and average density contrast $\sim-0.1$ aligned with the Cold Spot direction has been recently reported. It argued that, although first-order integrated Sachs-Wolfe (ISW) effect such on CMB is small, second-order Rees-Sciama (RS) contribution exceeds this by an order magnitude can entirely explain observed temperature profile. In paper we examine surprising claim using both exact calculation spherically symmetric Lema\^itre-Tolman-Bondi...

We study how the properties of cosmic voids depend on those tracer galaxy populations in which they are identified. use a suite halo occupation distribution mocks simulation, identify these using ZOBOV void finder and measure their abundances, sizes, densities dark matter content. To separate effects bias from sampling density, we do same for traced by randomly downsampled subsets simulation particles. At reduces total number ∼50 per cent can dramatically change size distribution. The...

The stacked density profile of cosmic voids in the galaxy distribution provides an important tool for use precision cosmology. We study profiles identified using ZOBOV watershed transform algorithm realistic mock luminous red (LRG) catalogues from Jubilee simulation, as well void constructed SDSS LRG and Main Galaxy samples. compare different methods reconstructing scaled by radius show that most commonly used method based on counts shells simple averaging is statistically flawed it...

We examine the integrated Sachs-Wolfe (ISW) imprint of voids and superclusters on cosmic microwave background. first study results from Jubilee $N$-body simulation. From Jubilee, we obtain full-sky ISW signal structures out to redshift $z=1.4$ a mock luminous red galaxy (LRG) catalogue. confirm that expected in concordance ΛCDM model is very small likely always be much smaller than anisotropies arising at last scattering surface. Any current detections such an must, therefore, predominantly...

The use of Eulerian 'standard perturbation theory' to describe mass assembly in the early universe has traditionally been limited modes with k $\lesssim$ 0.1 h/Mpc at z = 0. At larger SPT power spectrum deviates from measurements made using N-body simulations. Recently, there progress extending reach theory ideas borrowed effective field theory. We revisit computation redshift-space matter within this framework, including for first time full one-loop dependence. a resummation scheme proposed...

We consider observational constraints and fine-tuning issues in a renormalizable model of inflection point inflation, with two independent parameters. derive on the parameter space this arising from WMAP 7-year power spectrum. It has previously been shown that it is possible to successfully embed potential MSSM. Unfortunately, do requires severe fine-tuning. address issue by introducing hybrid field dynamically uplift subsequent smooth phase transition end inflation at necessary point. Large...

We investigate the hemispherical power asymmetry in cosmic microwave background on small angular scales. find an anomalously high multipole range ℓ = 601−2048, with a naive statistical significance of 6.5σ. However, we show that this extreme anomaly is simply coincidence three other effects, relativistic modulation, edge effects from mask applied, and inter-scale correlations. After correcting for all these level drops to ∼ 1σ, i.e., there no anomalous intrinsic Using null result, derive...

We present initial results from the Jubilee ISW project, which models expected \LambdaCDM Integrated Sachs-Wolfe (ISW) effect in simulation. The simulation volume is (6 Gpc/h)^3, allowing power on very large-scales to be incorporated into calculation. Haloes are resolved down a mass of 1.5x10^12 M_sun/h, allows us derive catalogue mock Luminous Red Galaxies (LRGs) for cross-correlation analysis with signal. find observed projected sky grow stronger at late times evolution spectrum matching...

I show that the most common method of quantifying likelihood an extreme galaxy cluster could exist is biased and can result in false claims tension with ΛCDM. This uses probability at least one above mass redshift observed cluster. demonstrate existence bias using sample populations, describe its origin explain how to remove it. then suggest potentially more suitable unbiased measures rareness individual clusters. Each different measure will be sensitive possible types new physics....

PYULTRALIGHT simulates the dynamics of ultralight dark matter in a non-expanding background. can describe evolution several interacting halos or one more orbiting central, fixed Newtonian potential, latter scenario corresponding to dwarf galaxies massive central galaxy. We verify by showing that it reproduces qualitative dynamical features previously published simulations and demonstrate has excellent energy-conservation properties. is implemented Python-based Jupyter notebook, solving...

There are observations of 15 high-redshift massive galaxy clusters, which have an extremely small probability with a purely Gaussian initial curvature perturbation. Here we revisit the estimation contribution non-Gaussianities to cluster mass function and point out serious problems that resulted in application range its validity. We remedy situation show values f_NL previously claimed completely reconcile (i.e. at ~100% confidence) existence clusters LambdaCDM unphysically small. However,...

The properties of large underdensities in the distribution galaxies Universe, known as cosmic voids, are potentially sensitive probes fundamental physics. We use data from MultiDark suite N-body simulations and multiple halo occupation mocks to study relationship between galaxy identified using a watershed void-finding algorithm, gravitational potential Φ. find that majority voids correspond local density minima larger scale overdensities, thus lie wells. However, subset can be closely trace...

We critically investigate current statistical tests applied to high redshift clusters of galaxies in order test the standard cosmological model and describe their range validity. carefully compare a sample high-redshift, massive, galaxy with realistic Poisson simulations theoretical mass function, which include effect Eddington bias. observations using following tests: distributions ensemble individual existence probabilities (in > M, z sense), distributions, 2d Kolmogorov-Smirnov test....

We consider methods with which to answer the question ``is any observed galaxy cluster too unusual for ΛCDM?'' After emphasising that many previous attempts this will overestimate confidence level at ΛCDM can be ruled out, we outline a consistent approach these rare clusters, allows answered. define three statistical measures, each of are sensitive changes in populations arising from different modifications cosmological model. also use properties ``equivalent mass redshift zero'' — an...

Number counts of massive high-redshift clusters provide a window to study primordial non-Gaussianity. The current quality data, however, forces the statistical analysis probe region parameter space---the extreme tail mass function---which is neither accessible in any currently available theoretical prescriptions for calculating function, nor calibrated $N$-body simulations. In this work we present new analytical prescription resummed non-Gaussian halo which constructed remain stable tail. We...

We discuss the universality and self-similarity of void density profiles, for voids in realistic mock luminous red galaxy (LRG) catalogues from Jubilee simulation, as well constructed SDSS LRG Main Galaxy samples. Voids are identified using a modified version ZOBOV watershed transform algorithm, with additional selection cuts. find that simulation self-similar, meaning their average rescaled profile does not depend on size, or -- within range simulated catalogue redshift. Comparison profiles...