0
$\begingroup$

I read about the cosmic pancakes, filaments and halos and I think I don't have much intuition about them.

First, what they are exactly are? are these shapes in which the matter in the universe is ordered?

Moreover, I read that pancakes corresponds to 1D, and I can't understand it geometrically. I thought that pancakes are large sheets (which is 2D !), filaments are kind of threads and halos are, well.. halos.

Can somebody please give me some intuiton and maybe visualize these structures?

Improve this question
$\endgroup$

1 Answer 1

Reset to default
1
$\begingroup$

Zeldovich pancake is a hypothetical structure that would form from a fluctuation soon after the Big Bang, then inflate to a supergalactical elipsoid and finally colapse. Zeľdovich approximated that on such big scales, the ellipsoid would shrink the fastest along the shortest axis. This would result in a flat elipse – a „pancake“ of galaxies.

Galaxy filaments are the largest known structures in the universe. They really are thread-like and could be likened to mycelium. It is believed that this structure is caused by the dark matter. A flatter subtype of galaxy filament is called a gallaxy wall.

Galactic halo is a much smaller subgalactical structure. Defining feature of a halo is that it's a spherical component of a galaxy. Typically they are made of stars (galactic spheroids), hot gases (galactic coronas) or dark matter (dark matter halos).

Improve this answer
$\endgroup$
2
  • $\begingroup$ Why pancakes are called 1d and not 2d? $\endgroup$
    – user
    Commented Oct 11, 2017 at 12:53
  • $\begingroup$ Lol, they're not. Can you cite any source? $\endgroup$
    – csha
    Commented Oct 12, 2017 at 7:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.