

5B light years across–the largest feature in the universe - dnetesn
http://phys.org/news/2015-08-billion-years-acrossthe-largest-feature.html

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wcoenen
xarchiv link to paper:

[http://arxiv.org/abs/1507.00675](http://arxiv.org/abs/1507.00675)

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fsloth
What is a definition of a "feature" in this instance? Does it just mean the
current state of a system that could be modeled as a single phase-space (i.e.
location plus momentum space for the non-physicists)?

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fsloth
No, really, I have MSc in physics but I have no idea what a thing being 'a
feature' specifically means in the cosmological sense - quick googling also
fails to find specification for the term.

If it's significant then it is significant within a specific model and
elements of said model should be able to be specified with logical precision -
otherwise the said model is kinda pointless.

Clearly what they are seeing is a large scale anisotropy - so what's the
treshold for an anisotropy to be considered to be 'a single structure' and how
is it measured?

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anti-shill
so if the universe is homogeneous on a large scale, and they keep finding ever
larger and larger structures that qualify as the largest structure discovered,
then the apparent size of the universe keeps getting larger and larger...so
the question is whether the universe is infinite...and that leads to another
question: if it is infinite, how can it ever end? The next question is, if an
infinite universe can never end, how can human life ever be extinguished?

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46Bit
> The next question is, if an infinite universe can never end, how can human
> life ever be extinguished?

Heat death. If the universe grows infinitely we'll eventually run out of stars
- but I'd worry far more about how we're treating Earth than such things.

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thecabinet
What clickbait pointlessness. We don't even really understand what causes
GRBs, but they're calling this as feature? Why not call the ring much farther
out in the picture a feature to? That seems only slight sillier.

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DanBC
> They appear to be at very similar distances from us – around 7 billion light
> years – in a circle 36° across on the sky, or more than 70 times the
> diameter of the Full Moon. This implies that the ring is more than 5 billion
> light years across, and according to Prof Balazs there is only a 1 in 20,000
> probability of the GRBs being in this distribution by chance.

I'd be interested to hear how they get this 1 in 20,000 figure.

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wereHamster
Hint: it's in the paper.

> 4.2 Verification of the ring structure

