The place of the Local Group in the cosmic web
Abstract
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 tidal tensor approach. We find that the LG's preferred location is regions with a dark matter overdensity close to the cosmic average. This makes filaments and sheets the preferred environment. We also find a strong alignment between the LG and the cosmic web. The orbital angular momentum is preferentially perpendicular to the smallest tidal eigenvector, while the vector connecting the two halos is strongly aligned along the the smallest tidal eigenvector and perpendicular to the largest tidal eigenvector; the pair lies and moves along filaments and sheets. We do not find any evidence for an alignment between the spin of each halo in the pair and the cosmic web.
- Publication:
-
The Zeldovich Universe: Genesis and Growth of the Cosmic Web
- Pub Date:
- October 2016
- DOI:
- 10.1017/S1743921316009819
- Bibcode:
- 2016IAUS..308..181F
- Keywords:
-
- cosmology: large-scale structure of universe;
- cosmology:dark matter;
- cosmology: simulations;
- Galaxy: formation