The relationship between Stress-Energy tensor and Mass

ShayanJ
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In Einstein field equations,the term that is responsible for curving Space-Time is the Stress-Energy tensor.But we know that mass should be able to curve space-time.So I think every mass distribution should have a Stress-Energy tensor associated with it.
What is that relationship?
Thanks
 
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Volumic mass density is the 00 component of the stress-energy tensor.
 
Shyan said:
In Einstein field equations,the term that is responsible for curving Space-Time is the Stress-Energy tensor.But we know that mass should be able to curve space-time.So I think every mass distribution should have a Stress-Energy tensor associated with it.
What is that relationship?
Thanks

The relationship is explained in Wikipedia here: http://en.wikipedia.org/wiki/Stress–energy_tensor

The simplest case is a perfect fluid at rest. In that case, the nonzero components of the stress-energy tensor T^{\alpha \beta} are:
T^{0 0} = \rho, where rho is the mass-energy density, and
T^{1 1} = T^{2 2} = T^{3 3} = p, where p is the pressure.
 
dextercioby said:
Volumic mass density is the 00 component of the stress-energy tensor.
Energy density, which is proportional to mass density only for a body at rest.
 
Thanks guys
But what about other components?
 
Shyan said:
Thanks guys
But what about other components?

As I said, for a fluid at rest, the three spatial components of the stress-energy tensor are just the pressure.
 
Shyan said:
But what about other components?

The diagram on the Wikipedia page identifies what the various components (or groups of them) represent.
 
Shyan said:
Thanks guys
But what about other components?

In addition to what Steven said, the off diagonal terms are shear stresses.
 
And of course you have momentum density...if you have a moving object or fluid.
 
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