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Centrifugal force for the observer in a rotating frame is a force as real as the force of gravity. However I know that gravitational force is an interaction between a mass and another. And the agent responsible is called graviton if I am not mistaken.

Centrifugal force on the other hand feels like gravity but no one is pulling or pushing. And it's even called ghost or pseudo force.

My question is that does centrifugal force appear only because of rotation or there are fundamental particles (photons, gravitons etc..) behind it?

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    $\begingroup$ In some way; a force is just whatever you want to define a force as. If you go by Newton’s Laws; centrifugal is not a force, as there is no ‘reaction’ force. If you just call a force anything that causes acceleration in some (not necessarily inertial) frame, then centrifugal is a real force. That being said; this very classical discussion is very far removed from QFT where force mediators start appearing. In QFT; even ‘foundational’ things like the definition of vacuum, or what constitues a ‘particle’; in some formal sense become observer dependent; especially in some accelerated frame $\endgroup$ Commented Sep 22, 2018 at 20:38
  • $\begingroup$ So am I kind of asking a question about apples that it is actually about oranges in some way?:) $\endgroup$ Commented Sep 22, 2018 at 20:42
  • $\begingroup$ It is the walls (or floor or whatever) that is pushing. That is what you feel. $\endgroup$
    – user137289
    Commented Sep 22, 2018 at 20:54
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    $\begingroup$ Gravitational force mediated by virtual gravitons is a naive popular interpretation. Gravitons cannot explain the curvature of spacetime. So gravity cannot be made just another quantum theory like QED or QCD. To unite gravity with the Quantum Field Theory, both must be changed to make spacetime variable instead of independent. In the meantime, according to the QFT approach, the centrifugal force in the rotating frame should be caused by gravitons. As Joshua Lin has mentioned above, in QFT, the existence of particles is observer dependent. These gravitons would exist only in the rotating frame. $\endgroup$
    – safesphere
    Commented Sep 23, 2018 at 7:53

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Are there any fundamental interactions behind centrifugal force?

Actually, there is no centrifugal force and therefore there is no physical interaction or agency behind it.

Imagine a bead on a frictionless rotating rod. The bead appears to accelerate radially relative to the rod, but, since there is no friction, there is no force acting on the bead in that direction.

Or imagine letting go on a merry-go-round - you are moving away from the center of rotation because there is no force holding you back.

What is a real force is a centripetal force, which forces objects to stay on a circle and, as the real force, is has a real physical interaction behind it, like a tension of a rope, the gravity forcing satellites go around the Earth or a normal reaction in a centrifuge.

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  • $\begingroup$ wouldn't a object will rotate in a circle only if it's centripetal and it's centrifugal acceleration or forces are same. If there is only one inward force namely centripetal force then it'll fall to the centre. @V.F $\endgroup$ Commented Sep 23, 2018 at 3:10
  • $\begingroup$ @Nobody recognizeable it's indeed constantly falling to the centre. $\endgroup$ Commented Sep 23, 2018 at 6:52
  • $\begingroup$ @physicsguy19 how's that revolving then. The distance from centre is same for all positions. If that's moving in a circle $\endgroup$ Commented Sep 23, 2018 at 7:59
  • $\begingroup$ @physicsguy19 and in the case the object will have to move spirally. $\endgroup$ Commented Sep 23, 2018 at 8:05
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    $\begingroup$ @Nobody Recognizeable check this figure. encrypted-tbn3.gstatic.com/… $\endgroup$ Commented Sep 23, 2018 at 9:05
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The force you feel in a centrifuge is due to the time rate of change of your velocity vector, which you experience as an acceleration. You get the same feeling in a car when you hit the gas, and in that case what is changing is the magnitude of your velocity vector and not its direction. In the centrifuge case, what is changing is the direction and not the magnitude of your velocity vector.

In either case, gravity is not involved, gravitons are not exchanged, and the forces are transmitted physically i.e., by material bodies pressing against each other while the electron clouds surrounding the atoms those bodies are made of resist that compression.

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  • $\begingroup$ so its of electromagnetic origin? $\endgroup$ Commented Sep 22, 2018 at 20:54
  • $\begingroup$ except for gravity, the pushes and pulls we humans experience in our ordinary lives are all electromagnetic in origin. $\endgroup$ Commented Sep 22, 2018 at 23:07

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