Gravitational Time and Length Change, Looking for mass formula

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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