this post was submitted on 01 May 2026
37 points (100.0% liked)

Ask Science

16476 readers
30 users here now

Ask a science question, get a science answer.

Community Rules

Rule 1: Be respectful and inclusive.Treat others with respect, and maintain a positive atmosphere.

Rule 2: No harassment, hate speech, bigotry, or trolling.Avoid any form of harassment, hate speech, bigotry, or offensive behavior.

Rule 3: Engage in constructive discussions.Contribute to meaningful and constructive discussions that enhance scientific understanding.

Rule 4: No AI-generated answers.Strictly prohibit the use of AI-generated answers. Providing answers generated by AI systems is not allowed and may result in a ban.

Rule 5: Follow guidelines and moderators' instructions.Adhere to community guidelines and comply with instructions given by moderators.

Rule 6: Use appropriate language and tone.Communicate using suitable language and maintain a professional and respectful tone.

Rule 7: Report violations.Report any violations of the community rules to the moderators for appropriate action.

Rule 8: Foster a continuous learning environment.Encourage a continuous learning environment where members can share knowledge and engage in scientific discussions.

Rule 9: Source required for answers.Provide credible sources for answers. Failure to include a source may result in the removal of the answer to ensure information reliability.

By adhering to these rules, we create a welcoming and informative environment where science-related questions receive accurate and credible answers. Thank you for your cooperation in making the Ask Science community a valuable resource for scientific knowledge.

We retain the discretion to modify the rules as we deem necessary.

founded 2 years ago
MODERATORS
sabbah@lemmy.world
AradFort@lemmy.world
ken_cleanairsystems@lemmy.sdf.org
count_of_monte_carlo@lemmy.world
37
Why does acceleration break symmetry in special relativity? (lemmy.ca)
submitted 1 day ago by a_gee_dizzle@lemmy.ca to c/askscience@lemmy.world
13 comments fedilink hide all child comments
 

As I understand it, in special relativity, when two bodies are moving away from one another, there is no absolute sense in which one is moving away from the other (e.g. when you jump in the air it is equally true to say that the Earth is moving away from you as it is to say that you are moving away from the Earth; or when a spaceship is going deep into space it's just as true to say that the Earth is moving away from the spaceship as it is to say the spaceship is moving away from Earth).

This has interesting implications when it comes to the more funky aspects of special relativity (i.e. time dilation, length contraction). Because this means that if Bob is moving close to light speed relative to Jane, Bob will perceive Jane as experiencing length contraction and time dilation, but Jane will not experience these things. From her point of view, it is Bob that is experiencing length contraction and time dilation. So both will always experience the other as experiencing these things, because from their point of view it is always the other person moving at near light speeds. So special relativity is symmetrical this way.

As I understand it though, this symmetry breaks when it comes to acceleration. This is how you can have a scenario where e.g. Bob ages a lot compared to Jane (because he accelerated or decelerated more).

So my question is: why does this symmetry in special relativity break when it comes to acceleration?

you are viewing a single comment's thread
view the rest of the comments
[–] a_gee_dizzle@lemmy.ca 3 points 20 hours ago (1 children)

I can confirm that it was

[–] musicalphysics@discuss.online 2 points 19 hours ago (1 children)

Ha! Awesome. Happy to know that even though I’m not a professor anymore there are still places where I can inspire more physics questions.

[–] Apytele@sh.itjust.works 1 points 7 hours ago* (last edited 7 hours ago)

I recently made a comment that "the sun and stars being holes in the fabric of the celestial sphere through which the light of heaven shines through" is a really weird way to describe gravity wells in the fabric of spacetime emotion emitting the energy of solar fusion that created the elements we're all made of but that was mostly a joke and not directly inspired by you.