this post was submitted on 30 Oct 2024
564 points (95.8% liked)

Science Memes

10923 readers
2274 users here now

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.

Rules

  1. Don't throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.

Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 2 years ago
MODERATORS
[email protected]
[email protected]
[email protected]
564
You have 8 seconds. (mander.xyz)
submitted 1 week ago by [email protected] to c/[email protected]
133 comments fedilink hide all child comments
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 23 points 1 week ago* (last edited 1 week ago) (2 children)

I don't understand. What's a uniform gravitational field and why does being inside one feels like standing in an accelerating elevator?

[–] [email protected] 28 points 1 week ago (1 children)

This is a joke about Einstein's form of the Equivalence Principle:

https://en.m.wikipedia.org/wiki/Equivalence_principle

[–] [email protected] 8 points 1 week ago* (last edited 1 week ago) (1 children)

Thanks. Let's see:

The weak equivalence principle, also known as the universality of free fall or the Galilean equivalence principle can be stated in many ways.

And

"... in a uniform gravitational field all objects, regardless of their composition, fall with precisely the same acceleration." "The weak equivalence principle implicitly assumes that the falling objects are bound by non-gravitational forces."[11]

I'm just beginning to understand. I'm not there yet.

[–] [email protected] 29 points 1 week ago (1 children)

If you are standing in a closed box, there is no experiment you can make that tells you whether that box is standing on earth, or is on a rocket in space accelerating at 9.81m/s²

This has a bunch of interesting implications about the nature of spacetime

[–] [email protected] 12 points 1 week ago* (last edited 1 week ago) (1 children)

It's just that normal gravity on earth feels exactly like being in an accelerating elevator in space. So you can't tell the difference from the inside. Like in the elevator you can ask them, whether you're still on earth or accelerating in space. Einstein used this thought experiment to develop the general theory of relativity.

Basically Einstein thinking about that weird feeling you get in your gut when an elevator starts upwards led to him concluding that mass bends spacetime making light from distant stars go in curves around the sun, which was confirmed during the next available solar eclipse.

[–] [email protected] 3 points 1 week ago

Aaah. I understand. :)