The World Doesn't Revolve Around You

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SUMMARY

The discussion centers on the concept of mass and gravitational influence, specifically addressing the question of how much mass an object would need to possess for Earth to revolve around it. Participants clarify that "revolve around" implies a mutual orbit around a shared center of mass. It is established that no object can be truly stationary in space, as all celestial bodies are in motion due to gravitational interactions. Ultimately, the conversation concludes that the question is ill-posed, as there is no definitive answer without precise definitions of terms like "stationary" and "center of mass."

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You know that saying?
"The world doesn't revolve around you"

If by "world" we'll use Earth ... how much mass would one need for the Earth to literally revolve around the subject?

Thanks in advance.
 
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I think you may have to more precisely define "revolve around".
 
Orbit?
Just like the Earth revolved around the sun.
Just like the Earth orbits the sun.
 
Imagine you have two objects mass of the Earth revolving around their center of mass. That means they both revolve around a point lying exactly in the middle between both of them. (For simplicity let's assume they are point masses and they are not destroyed by tidal forces blah blah blah).

Which one revolves around which?
 
Well what if I was stationary. I'm not orbiting around anything.
So if I am not moving, how much mass then?
 
There is no such thing as "stationary". Or, if you want to assume you are stationary and everything happens in a coordinates centered around you, world always revolves around you, no matter what your mass is.

I am afraid you are trying to ignore physical reality and find an answer to ill posed question. There is no answer.
 
The Sun itself is not stationary -- it is being pulled around by the motion of the planets. So even the mass of the Sun is insufficient.
 
I was thinking about something like "center of the mass is inside of the body". But it has to be clearly stated.
 
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