Quantcast
  • Register
PhysicsOverflow is a next-generation academic platform for physicists and astronomers, including a community peer review system and a postgraduate-level discussion forum analogous to MathOverflow.

Welcome to PhysicsOverflow! PhysicsOverflow is an open platform for community peer review and graduate-level Physics discussion.

Please help promote PhysicsOverflow ads elsewhere if you like it.

News

New printer friendly PO pages!

Migration to Bielefeld University was successful!

Please vote for this year's PhysicsOverflow ads!

Please do help out in categorising submissions. Submit a paper to PhysicsOverflow!

... see more

Tools for paper authors

Submit paper
Claim Paper Authorship

Tools for SE users

Search User
Reclaim SE Account
Request Account Merger
Nativise imported posts
Claim post (deleted users)
Import SE post

Users whose questions have been imported from Physics Stack Exchange, Theoretical Physics Stack Exchange, or any other Stack Exchange site are kindly requested to reclaim their account and not to register as a new user.

Public \(\beta\) tools

Report a bug with a feature
Request a new functionality
404 page design
Send feedback

Attributions

(propose a free ad)

Site Statistics

173 submissions , 136 unreviewed
4,271 questions , 1,618 unanswered
5,070 answers , 21,535 comments
1,470 users with positive rep
623 active unimported users
More ...

  Faster than light?

+ 0 like - 1 dislike
85 views

Hi, I have no actual knowledge in physics, but Iv'e been wondering about a specific (theoretical) idea that I had for quite a while now, so I decided to open an account here and ask if it's possible:

Let's say we have a very long pole made out of metal that reaches from earth all the way to some inhabitable planet 1 light year away.
If we were to pull on that pole 1 foot towards us, would it also move in the far away planet, instantaneously? 
Because if it does, isn't that faster than light?
And if not, does that mean the pole's length increased by 1 foot?
And if it is longer now, when the other end of the pole actually moves, will the pole go back to it's original length?
Because if the pole will eventually go back to it's original length, that would mean that metal is an elastic material.

I feel like there are too many contradictions if the answer to my first question is no.
I know it's not possible to actually execute this, but in theory?
 
What are your thoughts about this?

Closed as per community consensus as the post is not graduate-level
asked Aug 2, 2018 in Closed Questions by Eric Krief (-5 points) [ no revision ]
recategorized Aug 26, 2018 by Dilaton

As the pole is too massive, you will tear apart just a piece of it, and here you are.

I know it would be too massive, that's why I said in theory. Let's say it's from a super powerful material, and thin to reduce it's mass. 

In reality every material is "elastic", so a tension wave will propagate along the rod with a sound velocity or so.

Voting to close this question as of too low level.

This is not graduate-level, voting to close. 3000 rep users please upvote the closevote here if you agree.





user contributions licensed under cc by-sa 3.0 with attribution required

Your rights
...