Gravitational Time and Length Change, Looking for mass formula

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Mass remains constant in a gravitational field, despite the effects of gravitational time dilation and length contraction. While these phenomena affect the perception of time and size from an outside observer's perspective, they do not alter the intrinsic mass of an object. The discussion highlights confusion around the relationship between Planck time and Planck length, clarifying that they do not equate to an object's proper time or length. The conversation emphasizes the need for clear references and formulas to understand these concepts better. Overall, the consensus is that mass does not change due to gravitational effects.
mcjosep
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Hi, Just curious if anyone knows of a formula that would show how mass changes in a gravitational field? I have seen the formulas for gravitational time dilation and length contraction (which are rather similar) and was wondering is mass changes the same way.

Thanks
 
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Mass does not change in a gravitational field.
 
mcjosep said:
I have seen the formulas for gravitational time dilation and length contraction (which are rather similar)

What formulas have you seen for "gravitational length contraction"?
 
Just to pick an extreme, a 1kg ball is a meter away from the event horizon of a black hole. So, to an outside observer, time is almost not moving at all for the 1 kg ball and its size has shrunk to almost a point due to gravitational length and time dilation but the ball would still be 1 kg?
 
PeterDonis said:
What formulas have you seen for "gravitational length contraction"?

hmm i just figured since Planck time and Planck length are related by a factor of c that they would change the same.
 
mcjosep said:
its size has shrunk to almost a point due to gravitational length

What are you basing this on? What formula? Do you have a reference?

mcjosep said:
i just figured since Planck time and Planck length are related by a factor of c that they would change the same.

The Planck time and Planck length are not the same as the length of an object or its proper time.
 

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