General Relativity: The Equivalence Principle

The equivalence principle is key to understanding that light is deflected by gravity, and to understanding gravitational redshift.

Category:

Education

Tags:

• gravity
• clocks
• time
• light
• general
• relativity
• equivalence
• principle

[sweetser]

I have had trouble with this standard rocket ship explanation because no advanced culture could construct a rocket ship that accelerates at 9.8 m/s^2 for 4 billion years, like we have on this rock. I thought Ring World was a better model for gravity because it also has tides. Thought experiment: take all the mass in the Earth, make a super dense, thin shell that has all the mass, drill a hole, walk inside. Weight would depend on rotational speed of the shell.

[drdwittman]

@sweetser The point is, it's a thought experiment which allows us to discover otherwise-unexpected consequences of living in a gravitational field. It's not really a "model for gravity."

[fatcornerback]

Thanks!



[fax8]

Thanks for sharing your explaination.. pretty useful.

[moonwebber]

Thanks for explaining redshift! :)

[andrewkbradshaw]

Pretty neat! Great way to explain it.