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The Local Group (LG) of galaxies is dominated by the M31 and Milky Way (MW)pair, a configuration which suggests that the mass distribution in the LG andits surroundings should be highly anisotropic. We use the APOSTLE cosmologicalsimulations to examine how this anisotropy manifests on the spatialdistribution and kinematics of dwarf galaxies out to a distance of 3 Mpc fromthe MW. The simulations indicate a clear preference for dwarfs to be locatedclose to the axis defined by the MW-M31 direction, even for dwarfs in the LGperiphery (LGP; i.e., those at distances 1.25<d/Mpc<3). The LGP "Hubble flow"is also affected; at fixed distance from the MW the mean recession speed,<V_{rad} >, varies with angular distance to M31, peaking in the anti-M31direction and reaching a minimum behind M31. The combined M31-MW massdecelerates the local expansion; the LG "turnaround radius" (where <V_{rad}>=0)in APOSTLE is located at r ~ 1.25 Mpc from the LG barycentre and the pureHubble flow (where <V_{rad}> ~ H_0*d) is not reached out to at least 3 Mpc. Thepredicted flow is very cold, with a barycentric dispersion of <40 km/s. Acomparison of these predicted features with existing observations gives mixedresults. There is clear observational evidence for an angular anisotropy inV_{rad} around the LGP, but little evidence for a preferred spatialdistribution of LGP dwarfs along the MW-M31 axis. The observed local Hubbleflow is also peculiar. Although the coldness of the flow is consistent with thesimulations, it is significantly less decelerated: relative to the MW, onaverage, all galaxies beyond d~1.25 Mpc seem to be on a pure Hubble flow. Weargue that these oddities may result from incompleteness and inhomogeneous skycoverage, but a full explanation may need to await the completion of deepall-sky surveys able to fill the gaps in our current inventory of nearbydwarfs.

Anisotropies in the spatial distribution and kinematics of dwarf galaxies in the Local Group and beyond