this post was submitted on 25 Jul 2024
1138 points (99.2% liked)

Science Memes

10340 readers
1814 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.


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
 
you are viewing a single comment's thread
view the rest of the comments
[โ€“] [email protected] 33 points 1 month ago (1 children)

You are being downvoted as if your point was offensive or harmful. You are wrong, but it's totally counter intuitive and I think this is a mistake that everyone makes when studying introductory physics. This would be correct for anything moving at relatively low speeds. But when you're talking about light, or anything that goes so fast that "percentage of the speed of light" starts being a useful unit to describe their speed, this concept starts being a bit weirder.

This is actually the basic principle of Einstein's theory of relativity: the speed of light (in a vacuum) is the same for all observers, regardless of their frame of reference. That means that if the laser pointer emits a laser, the light is moving away from the pointer at the speed of light. If the pointer itself is moving at a speed reeeeeally close to the speed of light... Then the laser will STILL be traveling away from the pointer at the speed of light. And if you, an observer in a frame, see the pointer moving at near the speed of light emit a laser... The laser that the laser emitted is also traveling at the speed of light from your point of view.

And there's no wordplay here. I don't mean that it's light, so of course any speed it travels at is the speed of light. I mean that if you measure its speed from any reference frame, you will get around 300000000 m/s, or around 671 million miles per hour. No matter if you are also traveling at near light speed.

[โ€“] OneWomanCreamTeam 15 points 1 month ago