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Comment by irthomasthomas | Hacker News Reader

Just when you thought the vastness of space could not get any more mind blowing, you learn about filaments and superstructures spanning billions of light years.

https://en.wikipedia.org/wiki/Hercules%E2%80%93Corona_Boreal...

This one measures 10 billion light years. Now recall that 1 light year is about 10 trillion kilometers... tick, tick, tick, boom! Mind blown again.

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This video on the Great Attractor, which is pulling our galaxy towards it, gives a nice overview of superstructures: https://youtu.be/0w4OTD4L0GQ

See this excellent video on the scale of the cosmos: https://youtu.be/4iC9Qi3y9q8

And this one on how the universe would meet its fate at the hands of Dark Energy: https://youtu.be/fdFf5PRPE9g

This one on the emptiness of the universe is quite fascinating as well: https://youtu.be/BCjWmfWq0pU

Here's another fun one - a time lapse of the universe: https://www.youtube.com/watch?v=uD4izuDMUQA

Basically suggesting that if our universe was a human life, we'd still be in the hospital right after birth. So much time left to go.

I recall feeling a lot of existential dread when reading https://en.wikipedia.org/wiki/Timeline_of_the_far_future ... and this video just dug all that up again :)

Thanks for these links. TIL about this YT channel, and I was impressed with the quality.

Thanks so much for these links.

Just watched the first one and it was great.

Looking forward to the rest.

I like these two from the authors of the Laniakea super cluster paper in 2014

Nature: https://youtu.be/rENyyRwxpHo

Contributing Author: https://youtu.be/Ayj4p3WFxGk

Is there a book which describes and explains all such things in detail for common public?

Stephen Hawking's A Brief History of Time comes to mind: https://wiki2.org/en/A_Brief_History_of_Time

To stay at the scale of our galaxy:

> Filaments within clusters are separated from one another at perfectly equal distances — about the distance from Earth to the sun.

Does that mean that they are able to distinguish individual filaments that are "only" 1 AU apart, but ~ 25 000 light years (~1 600 000 000 AU) away from us? Because that would also be damn impressive!

I think they messed up. I quickly scanned and couldn't find any reference to what they are talking about in the paper, but if you look at the resolutions involved it's much more likely they are talking about parsecs, which is defined as 'the distance from the sun at which 1 AU subtends a distance of 1 arcsecond' or a little over 3 light years.

Paper is here - https://arxiv.org/pdf/2201.10541.pdf

(Edit:Yes take a look at the images and scale bars on page 14)

The angular separation would be only 0.00013 arcseconds, so very impressive indeed. Hubble has an angular resolution of around 0.05 arcseconds in comparison. Radio telescopes can get better angular resolution than that using interferometry between distantly separated telescopes. Perhaps that's how they can do it.

The reported angular resolution (in the main paper: https://arxiv.org/abs/2201.10541) is 4 arcseconds. This is radio interferometry, which makes for better resolution, but it’s at a very low frequency (centered around 1.28 GHz = about 23 cm), which makes for worse resolution.

We need warp drive technology ASAP so we can go see what these things taste like.

You fool! Don't you realize where these filaments come from? There's an old example from a distant galaxy that demonstrates their formation. [1]

[1] https://www.youtube.com/watch?v=s2hM1tyEL0U&t=1m29s

Perhaps these strings pertain to a warp drive super highway

"And, while Yusef-Zadeh already knew the filaments are magnetized, now he can say magnetic fields are amplified along the filaments, a primary characteristic all the filaments share."

Yup - definitely related to warp drive tech ;)

Warp drive contrails.

While type 0 civilizations grapple with chemtrails, type 3 civilations grapple with magtrails.

Tendrils of intergalactic mind control drugs! Wake up space-shaliens!

Warp drive chemtrails! :)

Looks more like a highly scalable railgun.

Better question: will it blend?

Most likely they taste like chicken.

Thats totally ungraspable for human brains, mind blowing! Thats 10^23 kilometers, the same order of magnitude as the avogardo constant, means e.g. 14 gramms of carbon correspond to about 6.22 * 10^23 atoms of carbon, its the same magnitude to some of the larger smallest things...

You can a bit actually by scaling down everything. Imagine earth is the size of a grain of sand. Nearest star would beat approximately 4000km away. Light would travel at 0.3m/sec. Moon is only 4mm away. The sun only 16 meters.

I think you're missing a zero and must mean 0.03 m/s for light. Otherwise, your other distances have the wrong order of magnitude in terms of light-seconds.

Even 0.003 m/s, since the moon is about one light secon away.

and how long is this strand in question?

In this model, the sun is 16 metres away and is 8 light minutes in real money.

The strands from the article are 150 light years which is seventy eight million, eight hundred and ninety four thousand light minutes (78894000lm) or nine million, eight hundred and sixty one thousand, seven hundred and fifty times the distance of the sun (9861750x) which gives us 16mx9861750 or one hundred and fifty seven thousand, seven hundred and eighty eight km (157788km). About 40% of the way to the (real) moon.

If you mean the Hercules Great Wall, 10 billion light years is five quadrillion, two hundred and fifty nine trillion, six hundred billion light minutes (5259600000000000lm) which gives us six hundred and fifty seven trillion, four hundred and fifty billion (657450000000000x) times the distance to the sun which would be ten trillion, five hundred and nineteen billion, two hundred and million km (10519200000000km). Or "quite big".

Love it, thanks. Turns out it isn't actually very realistic to approximate the Hercules Great Wall. Astonishing

These numbers do not mean anything. Our mind can naturally process small numbers (units, then "it is a small group", then "it is a big group").

One million, when not attached to something tangible, cannot be processed. A house is one million euros - that I can get. What is one million protons side to side - I have no idea.

Of course, I can calculate that 10^6x10^-15 m is 10^-9 m. Right..

Same goes for scale. If I say - twice the width of a tree you immediately get an idea. Twide the width of a hair - not much. A million times the width of a hair - neither.

So 10^9x10^12x10^3 m = 10^24m, looks it is a lot.

To claim that the fact that (most?) humans' lack of hardware for processing numbers with exceptionally large or small magnitudes is equivalent to the numbers not meaning anything is... odd. Isn't the whole point of learning, curiosity, and even articles like this to assist us in developing our own internal software to increase understanding beyond what our naive hardware can do?

I do not understand.

Do you know how large 50000 bacteria side to side are? I don't. I can compute the number but these are neither scales nor magnitudes I am used to.

300,000 km seems to be large but I do not know how much. About 10 times the perimeter of our planet. But this does not say much either.

But when you say "five people in a room, and then two joined" you have no problems processing the numbers.

See, e.g., holoduke's comment in this thread. The main tool that I (I'd say "we", but I know that different folks visualize differently) have for understanding the scale of the universe is analogy. It's absolutely non-trivial to understand (grasp / grok / missing English verb) this sort of thing -- but it's absolutely possible to continue to get better at it, and to comprehend more and more as you learn and experience more and more.

An individual person can't point at something they don't comprehend and rightly claim it is meaningless. I'd argue the same is true in the extreme: if something can't be comprehended by _anyone_, that doesn't make it meaningless.

How do people make microchips, without understanding precisely and intimately how physics works at the scale of nanometers? Just because you don't isn't proof that nobody can.

When time and space become increasingly intertwined and obscure as we are looking towards big bang, I really think that our perception of "structure" has to be perceived completely differently than we do now.

We witness structure in a 3d space, have to add time to that dimension and yet look onto something back in time, when commonly agreed fixtures like the fine structure constant might have had a different value or not exist at all.

Working link: https://en.wikipedia.org/wiki/Hercules%E2%80%93Corona_Boreal...

Thanks!

Or one could say the speed of light is pretty slow on the cosmic scale

If you like thinking about cosmic scales and deep time, Stephen Baxter's Xeelee Sequence may appeal (try to look past the schlocky name) .

Without too many spoilers, the coarse structure of the universe is imagined to be able to be manipulated into tools and weapons.

A structure that’s 10 billion light years is crazy, given that observable universe Israel itself is 93 billion light years.

I wanted to see this written out so here goes:

1,000,000,000,000

x 10,000,000,000

-----------------------

10,000,000,000,000,000,000,000

10 ** 22

Aka Ten Sextillion

What exactly is it?

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