Another largest structure in the Universe?

Just after they discovered a structure in the universe what was 4
billion light-years long, now they've discovered one that's 10 billion
light-years long! Pop goes the Cosmological Principle!

Yousuf Khan

"Until now, the largest known structure in the Universe was the Huge-LQG (Large Quasar Group), a cluster of 73 quasars stretching over a distance of 4 billion light years. Now astronomers say they've spotted something even bigger in data from gamma ray bursts, the final explosions of energy released by stars as they die and the universe's most energetic events. Astronomers have measured the distance to 283 of these bursts and mapped their position in the universe. This throws up a surprise. At a distance of ten billion light years, there are more gamma ray bursts than expected if they were evenly distributed throughout the universe. This implies the existence of a structure at this distance that is about ten billion light years across and so dwarfs the Huge-LQG. What's odd about the discovery is that the Cosmological principle--one of the fundamental tenets of cosmology--holds that the distribution of matter in the universe will appear uniform if viewed at a large enough scale. An
d yet, structures clearly emerge at every scale astronomers can see. The new discovery doesn't disprove the principle but it does provide some interesting food for thought for theorists."

Astronomers Discover Largest Structure In the Universe - Slashdot
http://science.slashdot.org/story/13...n-the-universe

Astronomers Discover Largest Structure in the Universe — The Physics
arXiv Blog — Medium
https://medium.com/the-physics-arxiv-blog/267ddcb8057b

Wow, there's seriously freaking big and massive stuff out there.

"Yousuf Khan" wrote in message
...
Just after they discovered a structure in the universe what was 4 billion
light-years long, now they've discovered one that's 10 billion light-years
long! Pop goes the Cosmological Principle!

Yousuf Khan

"Until now, the largest known structure in the Universe was the Huge-LQG
(Large Quasar Group), a cluster of 73 quasars stretching over a distance
of 4 billion light years. Now astronomers say they've spotted something
even bigger in data from gamma ray bursts, the final explosions of energy
released by stars as they die and the universe's most energetic events.
Astronomers have measured the distance to 283 of these bursts and mapped
their position in the universe. This throws up a surprise. At a distance
of ten billion light years, there are more gamma ray bursts than expected
if they were evenly distributed throughout the universe. This implies the
existence of a structure at this distance that is about ten billion light
years across and so dwarfs the Huge-LQG. What's odd about the discovery
is that the Cosmological principle--one of the fundamental tenets of
cosmology--holds that the distribution of matter in the universe will
appear uniform if viewed at a large enough scale. An
d yet, structures clearly emerge at every scale astronomers can see. The
new discovery doesn't disprove the principle but it does provide some
interesting food for thought for theorists."

Astronomers Discover Largest Structure In the Universe - Slashdot
http://science.slashdot.org/story/13...n-the-universe

Astronomers Discover Largest Structure in the Universe — The Physics arXiv
Blog — Medium
https://medium.com/the-physics-arxiv-blog/267ddcb8057b

On 12/27/13, 2:27 AM, Brad Guth wrote:
Wow, there's seriously freaking big and massive stuff out there.

That's what she said... when she was about to slam into the moon.

On 12/27/2013 6:33 AM, Sam Wormley wrote:
On 12/27/13, 2:27 AM, Brad Guth wrote:
Wow, there's seriously freaking big and massive stuff out there.

That's what she said... when she was about to slam into the moon.


With this one and a few more to come, there's not much chance of any
missing mass within our universe.

In article ,
Yousuf Khan writes:
Just after they discovered a structure in the universe what was 4
billion light-years long, now they've discovered one that's 10 billion
light-years long! Pop goes the Cosmological Principle!

Bit early for that, even if the results hold up. We know there are
random structures in the Universe, and it isn't yet clear how large
the largest such structure "should be" based on current cosmology.

For those interested, the preprint is at
http://arxiv.org/abs/1401.0533
Statistical significance is something less than 1/1000, but how much
less isn't clear. (It's probably at least a factor of 9.)

Most interesting to me is Fig 3, which shows an excess of GRBs in the
relevant redshift range (1.6z2.1 if I understand the article
properly) in the north ecliptic pole region compared to the SEP.
This could well be observational bias: the ecliptic poles are more
heavily observed for GRBs, and followup is more extensive in the
north than in the south. The mystery, though, would be why only one
particular redshift range shows an anisotropy. I can imagine at
least one possible reason for that but can't justify it in detail.
However, the obvious correlation with terrestrial observing patterns
suggests caution.

This is an intriguing observation, but we need a larger sample of
objects.

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