EP and active/passive mass

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In summary, EP (energy potential) is a measure of the stored energy in an object due to its mass and position. Active mass refers to the mass of an object that is actively participating in a physical process, while passive mass refers to the mass of an object that is not actively participating but is still affected by external forces. These two masses can be equal in some cases, but are typically different due to external forces. The mass of an object directly affects its EP, with heavier objects having a greater EP. EP can be calculated using the formula EP = mgh, where m is the mass, g is the acceleration due to gravity, and h is the height or position of the object.
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If we start from an action in which geometry and matter are non-minimally coupled, can the resulting theory have a covariantly conserved stress-energy tensor (if so, what is the stress-energy tensor in terms of the action?)

In Newtonian physics the EP (equivalence of inertial/passive mass) and the third law (equivalence of passive/active mass, momentum conservation) are not linked. I'd naively guess that violating the EP (minimal coupling) will cause non-conservation of stress-energy-momentum so that these are linked in GR, if not in Newtonian gravity.
 
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@atyy did you have any more insight on this?
 

FAQ: EP and active/passive mass

What is EP in relation to mass?

EP stands for "energy potential" and is a measure of the stored energy in an object due to its mass and position. It is often used in physics to calculate the amount of work that can be done by an object.

How is active mass different from passive mass?

Active mass refers to the mass of an object that is actively participating in a physical process, such as moving or exerting force. Passive mass, on the other hand, refers to the mass of an object that is not actively participating in a physical process but is still affected by external forces.

Can active mass and passive mass be equal?

Yes, active mass and passive mass can be equal in some cases. For example, if an object is at rest and not exerting any force, its active mass and passive mass would be the same. However, in most cases, the two will be different as there is usually some external force acting on an object, causing a difference between its active and passive mass.

How does mass affect an object's EP?

The mass of an object is directly related to its EP. The heavier the object, the greater its EP will be. This is because the object has more stored energy due to its greater mass. Additionally, the position of the object can also affect its EP, as a higher position typically results in a greater EP.

How is EP calculated?

EP can be calculated using the formula EP = mgh, where m is the mass of the object, g is the acceleration due to gravity, and h is the height or position of the object. This formula can be used to calculate the EP for an object at rest or in motion, as long as its mass and position are known.

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