<p><a href="https://en.wikipedia.org/wiki/Topological_defect#Cosmological_defects" rel="nofollow noreferrer">A Domain Wall is an &quot;topological defect&quot; and a 2-dimensional singularity.</a> They are widely theorized to exist throughout the universe, but none have been detected yet. I'm having trouble understanding what they actually are though, the wikipedia articles and papers I looked at just have a lot of advanced mathematics.</p>
<ol>
<li>Can light pass through a Wall? Do they emit/reflect any light.</li>
<li>Can matter pass through a Wall? If I were in a spacecraft, and I passed through a Wall, what would I see?</li>
<li>If it is a 2-d singularity, does it have an event horizon?</li>
<li>Does it have charge and spin like a black hole?</li>
</ol>

CC BY-SA 4.0
2023-04-04T21:50:15.600Z
is https://arxiv.org/pdf/hep-th/9604090.pdf the sort of thing you're talking about?  Or https://guava.physics.uiuc.edu/~nigel/courses/569/Essays_Fall2012/Files/LIU.pdf
James K
CC BY-SA 4.0
2023-04-04T22:22:35.053Z
@JamesK The second one, https://en.wikipedia.org/wiki/Topological_defect#Cosmological_defects
qazwsx
CC BY-SA 4.0
2023-04-04T22:32:11.247Z
I'm not sure whether 'wildly' wouldn't be the more appropriate adverb than 'widely'.
planetmaker
CC BY-SA 4.0
2023-04-04T22:33:15.087Z
From wikipedia " if domain walls [...] were present in the observable universe, they would result in significant deviations from what astronomers can see."
James K
CC BY-SA 4.0
2023-04-04T22:48:49.267Z
vaguely related: https://www.youtube.com/watch?v=lYN9GWS1xjM
planetmaker
CC BY-SA 4.0
2023-04-05T07:23:54.250Z
"Significant deviations" is about as vague as you can get
qazwsx
<astrophysics><high-energy-astrophysics><singularity>
What exactly IS a "Domain Wall"?
qazwsx
# What exactly IS a "Domain Wall"?

(Asked by: username_0 on 2023-04-04)

[A Domain Wall is an "topological defect" and a 2-dimensional singularity.](https://en.wikipedia.org/wiki/Topological_defect#Cosmological_defects) They are widely theorized to exist throughout the universe, but none have been detected yet. I'm having trouble understanding what they actually are though, the wikipedia articles and papers I looked at just have a lot of advanced mathematics.

1. Can light pass through a Wall? Do they emit/reflect any light.
2. Can matter pass through a Wall? If I were in a spacecraft, and I passed through a Wall, what would I see?
3. If it is a 2-d singularity, does it have an event horizon?
4. Does it have charge and spin like a black hole?

**Tags:** astrophysics, high-energy-astrophysics, singularity
> **Comments:**
> **username_1**: is https://arxiv.org/pdf/hep-th/9604090.pdf the sort of thing you're talking about?  Or https://guava.physics.uiuc.edu/~nigel/courses/569/Essays_Fall2012/Files/LIU.pdf  
> **username_0**: @JamesK The second one, https://en.wikipedia.org/wiki/Topological_defect#Cosmological_defects  
> **username_2**: I'm not sure whether 'wildly' wouldn't be the more appropriate adverb than 'widely'.  
> **username_1**: From wikipedia " if domain walls [...] were present in the observable universe, they would result in significant deviations from what astronomers can see."  
> **username_2**: vaguely related: https://www.youtube.com/watch?v=lYN9GWS1xjM  
> **username_0**: "Significant deviations" is about as vague as you can get  

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## 0 answers

