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Large-Scale structure of the universe videos
(i.e., Large-scale
structure of the universe videos):
High-cal ones:
- Blueprints of the Universe | 2:26:
This video from
ESO shows
a computer simulation
(probably an
N-body simulation)
of structure formation
(i.e., the formation of the
large scale structure
of the observable universe or
cosmic web).
The cosmic time of the
computer simulation is
NOT specified, but it probably spans from the
cosmic dark age (∼ 377 kyr (z ≅ 1100) -- ∼< 200 Myr (z ≅ 20))
to
cosmic present = to the age of the observable universe = 13.797(23) Gyr (Planck 2018).
Note that the overall
expansion of the universe
has been divided out of the
visualization
since otherwise the scale would change by viewed
large scale structure
would increase by a factor of ∼ 20 ????.
Yours truly thinks we are seeing
dark matter only.
The baryonic matter
is dragged by the dark matter.
So we are seeing the formation of
the dark matter halos
in which galaxies,
galaxy clusters, and
galaxy superclusters form.
We also see formation of
galaxy filaments and
cosmic voids: i.e.,
cosmic web
Structure formation
is initiated by
primordial fluctuations
in the primordial
density of
dark matter.
The higher
primordial fluctuations
attracted more
dark matter
by gravitation
and grew into
dark matter halos
overcoming the overall
expansion of the universe
and the lower
primordial fluctuations
fluctuations lost
dark matter and
grew into cosmic voids.
It's a case of the rich getter richer and the poor getting poorer.
The baryonic matter
(which is only ∼ 1/6 of the
dark matter) mostly just
followed the dark matter
and formed the primordial
galaxies in the
dark matter halos.
Due to
peculiar velocities
superimposed on the overall
expansion of the universe,
all kinds of
galaxy interactions and
galaxy mergers happened
leading to
hierarchical structure formation:
bigger structures forming by the accretion of smaller structures: i.e.,
galaxies merged into bigger
galaxies and these then merged
into galaxy clusters
and galaxy superclusters.
The video is a bit long, but good for
classroom.
- Supercomputer simulation of large scale
structures in the Universe | 1:12:
"Cosmological N-body simulation
of the formation and evolution of
large-scale structure
of the universe. The number of simulated particles is 512**3=134,217,728.
The size of the simulation box is ∼ 100 Mpc (∼ 300 Mly).
This simulation was carried on
the Cray XT4
at
Center
for Computational Astrophysics (CfCA) of
National
Astronomical Observatory of Japan.
Simulation and Visualization: Tomoaki Ishiyama (University of Tsukuba)" (Slightly edited.)
The simulation covers
cosmological redshift
z = 13.32 (i.e., cosmic time ∼ 0.32 Gyr)
to z = 0 (i.e.,
cosmic present =
to the age of the observable universe = 13.797(23) Gyr (Planck 2018))
(see "A Redshift Lookup Table for our Universe",
Sergey V. Pilipenko, 2013).
Good and short enough for the classroom.
- Large Scale Structure Formation | 1:01:
This N-body simulation
probably covers billions of years from
cosmic time t=0.1 Gyr to several
gigayears on.
By N-body simulation,
we mean there are NO stars
NOR baryonic matter
(i.e., ordinary matter of protons,
neutrons, and
electrons),
and
all the particles in the simulation (i.e.,
N-bodies)
represent a form of
dark matter
with NO interactions, except
gravity
and with NO specified
dark matter particle
mass---but the
N-bodies actually
are given a mass much larger
than what the
dark matter particle
mass is expected to be.
         
The brightness scales with density of dark matter
and is NOT an indication of emitted light.
We are watching the
dark matter halos form.
The dark matter particles
only interact through gravity.
That's why we see clumps flying through each other.
The baryonic matter
(which is much less in mass than the
dark matter) in reality
is pulled into the
gravitational wells
of the dark matter halos
and processed there into galaxies
and stars.
Good and short enough for the classroom.
- Reionization -
End of the Dark Ages of the Universe | 2:05:
The
reionization era
(cosmic time c.150 Myr --- z≅ 6, c.1 gyr for complete end)
that ended the
cosmic dark ages
(cosmic time z≅ 11000, c.377,000 years --- z≅ 6, c.1 gyr for complete end).
In the computer simulation,
the expanding bright regions are the reionized regions.
The reionization
was caused by mainly by
ultraviolet (UV) light
from the early galaxies
(i.e., their stars
and active galaxy nuclei (AGNs),
mainly quasars).
Pretty to look at, but it's NOT clear what we are seeing.
Iffy for the classroom.
- Laniakea: Our home supercluster | 4:10:
On the
Laniakea Supercluster,
our home
galaxy supercluster by
precise definition of
galaxy supercluster.
Good and, on a leisurely day,
short enough for the classroom.
- A Flight Through the Universe,
by the Sloan Digital Sky Survey | 1:49:
The flight is through
an actual to-scale
map of the local (i.e., contemporary)
observable universe out to
cosmological redshift z ≅ 0.13
and
cosmological proper distance
≅ 1.3 Gly ≅ 0.4 Gpc
and includes ∼ 400,000 galaxies.
The galaxy images are real images.
The flight is based on data from the
Sloan Digital Sky Survey (SDSS).
Good for the classroom.
Low-cal ones:
Local file: local link: large_scale_structure_videos.html.
File: Cosmology file:
large_scale_structure_videos.html.