Abstract:
We simulate the future evolution of the observed inhomogeneities in
the local universe assuming that the global expansion rate is
dominated by a cosmological constant. We find that within two Hubble
times (~ 30 billion years) from the present epoch, large-scale
structures will freeze in comoving coordinates and the mass
distribution of bound objects will stop evolving. The Local Group
will get somewhat closer to the Virgo cluster in comoving coordinates,
but will be pulled away from the Virgo in physical coordinates due to
the accelerated expansion of the Universe. In the distant future
there will only be one massive galaxy within our event horizon, namely
the merger product of the Andromeda and the Milky Way galaxies. All
galaxies that are not gravitationally bound to the Local Group will
recede away from us and eventually exit from our event horizon. More
generally, we identify the critical interior overdensity above which
a shell of matter around an object will remain bound to it at late
times.
Figures in the Paper:
(postscript & PDF files)
Other Figures:
structure snapshots at different times in the future
(t0=present time=13.5 Gyr; tH=Hubble time=14 Gyr) (1.8MB
postscript & 1MB PDF files)
Solid blue cirle = physical radius of 100Mpc/h.
Thick dashed red circle = event horizon at physical 3.6 Gpc/h.
Acknowledgement:
We are grateful to the authors of Mathis
et al. (2002) paper and the GIF (German-Israel Foundation)
collaboration for allowing us to use their z=0
simulation output as the initial condition of our simulation. In particular,
we thank Volker Springel
for providing us with the data in a convenient
format for the GADGET code,
as well as for clearing out some of our technical
problems and questions at the initial stage of this work.