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We explore the characteristics of the cosmic web around Local Group(LG) like pairs using a cosmological simulation in the $Lambda$CDM cosmology. We use the Hessian of the gravitational potential to classify regions on scales of $sim 2$ Mpc as a peak, sheet, filament or void. The sample of LG counterparts is represented by two samples of halo pairs. The first is a general sample composed by pairs with similar masses and isolation criteria as observed for the LG. The second is a subset with additional observed kinematic constraints such as relative pair velocity and separation. We find that the pairs in the LG sample with all constraints are: (i) Preferentially located in filaments and sheets, (ii) Located in in a narrow range of local overdensity $0<delta<2$, web ellipticity $0.1<e<1.0$ and prolateness $-0.4<p<0.4$. (iii) Strongly aligned with the cosmic web. The alignments are such that the pair orbital angular momentum tends to be perpendicular to the smallest tidal eigenvector, $hat{e}_3$, which lies along the filament direction or the sheet plane. A stronger alignment is present for the vector linking the two halos with the vector $hat{e}_3$. Additionally, we fail to find a strong correlation of the spin of each halo in the pair with the cosmic web. All these trends are expected to a great extent from the selection on the LG total mass on the general sample. Applied to the observed LG, there is a potential conflict between the alignments of the different planes of satellites and the numerical evidence for satellite accretion along filaments; the direction defined by $hat{e}_3$. This highlights the relevance of achieving a precise characterization of the place of the LG in the cosmic web in the cosmological context provided by $Lambda$CDM.
We use the Bolshoi Simulation to find the most probable location of the Local Group (LG) in the cosmic web. Our LG simulacra are pairs of halos with isolation and kinematic properties consistent with observations. The cosmic web is defined using a ti
The 80% of the matter in the Universe is in the form of dark matter that comprises the skeleton of the large-scale structure called the Cosmic Web. As the Cosmic Web dictates the motion of all matter in galaxies and inter-galactic media through gravi
We explore the evolution of halo spins in the cosmic web using a very large sample of dark matter haloes in the $Lambda$CDM Planck-Millennium N-body simulation. We use the NEXUS+ multiscale formalism to identify the hierarchy of filaments and sheets
Increasing evidence suggests that cosmological sheets, filaments, and voids may be substantially magnetized today. The origin of magnetic fields in the intergalactic medium (IGM) is, however, currently uncertain. It seems well known that non-standard
The growth of large-scale cosmic structure is a beautiful exemplification of how complexity can emerge in our Universe, starting from simple initial conditions and simple physical laws. Using {enzo} cosmological numerical simulations, I applied tools