<p>Lorentz symmetry is only global in flat space times; in free falling general relativistic reference frames, it is a local symmetry. So you don’t even have to go as far as outside the observable universe to find situations where Lorentz symmetry isn’t global, it’s happening right here in our observable universe whenever you have strong gravity regimes.</p>
<p><a href="https://arxiv.org/pdf/1403.7785.pdf" rel="nofollow noreferrer">Here</a> is a paper as a source for these claims.</p>
<p>It seems like your understanding of global vs local symmetries was kind of off to begin with and then compounded by ChatGPT; whether a symmetry is global or local is not a inside-the-observable-universe vs outside-the-observable-universe. With any luck, perhaps <a href="https://physics.stackexchange.com/questions/48188/local-and-global-symmetries">this question</a> on the physics SE can clear some stuff up for you on your misunderstandings there.</p>

CC BY-SA 4.0
2023-03-02T18:18:41.300Z
Well, I thought that we knew mathematically speaking that there could not be global symmetries in our universe but there were no observations, hence that is why I assumed that this would occur outside the observable universe. Anyways, it is not clear to me whether a symmetry that holds locally but not globally, then means that they hold true in some cases/regions of the universe and not others... @JustinT
vengaq
CC BY-SA 4.0
2023-03-02T20:21:31.133Z
Sorry I'm not totally sure I am understanding what you're saying. For example, baryon number is a global U1 symmetry (except under non-perturbative weak force interactions); what do you mean there are no observations?
Justin T
CC BY-SA 4.0
2023-02-27T03:31:57.120Z
2023-02-27T03:31:57.120Z
Justin T
<p>Perhaps this may be a stupid question but anyways here it goes...</p>
<p>If the Lorentz symmetry is not global but rather local, wouldn't that mean that is possible that other Hubble spheres outside our observable universe could have other symmetries or an absence of the Lorentz symmetry? I mean, does this mean that the Lorentz symmetry could hold in our local region of spacetime (that is, our observable universe) but, as it does not hold globally, there could be other regions where it would not hold?</p>

CC BY-SA 4.0
2023-02-26T18:38:03.860Z
Hello vengaq.  Asking a chat AI is like saying "I asked my dumb friend who knows nothing about science".  In other words, it isn't really "doing research".  The only difference is that your dumb friend might have the sense to say "I don't know" but Chat GTP doesn't. So, what actual research led you to ask this question?  I'd recommend removing all the GTP stuff, as it is only a distraction.
James K
CC BY-SA 4.0
2023-02-26T18:41:39.307Z
At a glance, Chat GTP doesn't have a clue what you are talking about. It is chatting about crystals in the first answer and about things like charge symmetry in the second answer.  Again.  I strongly recommend removing **everything** related to the AI answer.
James K
CC BY-SA 4.0
2023-02-27T01:14:16.360Z
@JamesK sorry, it's done
vengaq
<cosmology><general-relativity><observable-universe><special-relativity>
Other Hubble spheres with no Lorentz symmetry?
vengaq
# Other Hubble spheres with no Lorentz symmetry?

(Asked by: username_0 on 2023-02-26)

Perhaps this may be a stupid question but anyways here it goes...

If the Lorentz symmetry is not global but rather local, wouldn't that mean that is possible that other Hubble spheres outside our observable universe could have other symmetries or an absence of the Lorentz symmetry? I mean, does this mean that the Lorentz symmetry could hold in our local region of spacetime (that is, our observable universe) but, as it does not hold globally, there could be other regions where it would not hold?

**Tags:** cosmology, general-relativity, observable-universe, special-relativity

> **Comments:**
> **username_1**: Hello username_0.  Asking a chat AI is like saying "I asked my dumb friend who knows nothing about science".  In other words, it isn't really "doing research".  The only difference is that your dumb friend might have the sense to say "I don't know" but Chat GTP doesn't. So, what actual research led you to ask this question?  I'd recommend removing all the GTP stuff, as it is only a distraction.  
> **username_1**: At a glance, Chat GTP doesn't have a clue what you are talking about. It is chatting about crystals in the first answer and about things like charge symmetry in the second answer.  Again.  I strongly recommend removing **everything** related to the AI answer.  
> **username_0**: @username_1 sorry, it's done  

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## 1 answers

### Answer by username_2 on 2023-02-27. Score: 3

Lorentz symmetry is only global in flat space times; in free falling general relativistic reference frames, it is a local symmetry. So you don’t even have to go as far as outside the observable universe to find situations where Lorentz symmetry isn’t global, it’s happening right here in our observable universe whenever you have strong gravity regimes.

[Here](https://arxiv.org/pdf/1403.7785.pdf) is a paper as a source for these claims.

It seems like your understanding of global vs local symmetries was kind of off to begin with and then compounded by ChatGPT; whether a symmetry is global or local is not a inside-the-observable-universe vs outside-the-observable-universe. With any luck, perhaps [this question](https://physics.stackexchange.com/questions/48188/local-and-global-symmetries) on the physics SE can clear some stuff up for you on your misunderstandings there.

> **Comments:**
> **username_0**: Well, I thought that we knew mathematically speaking that there could not be global symmetries in our universe but there were no observations, hence that is why I assumed that this would occur outside the observable universe. Anyways, it is not clear to me whether a symmetry that holds locally but not globally, then means that they hold true in some cases/regions of the universe and not others... @username_2  
> **username_2**: Sorry I'm not totally sure I am understanding what you're saying. For example, baryon number is a global U1 symmetry (except under non-perturbative weak force interactions); what do you mean there are no observations?  

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