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Active Mass Under Pressure

Juergen Ehlers·Istvan Ozsvath·Engelbert Schucking
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Abstract

After a historical introduction to Poisson's equation for Newtonian gravity, its analog for static gravitational fields in Einstein's theory is reviewed. It appears that the pressure contribution to the active mass density in Einstein's theory might also be noticeable at the Newtonian level. A form of its surprising appearance, first noticed by Richard Chase Tolman, was discussed half a century ago in the Hamburg Relativity Seminar and is resolved here.

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Juergen Ehlers, Istvan Ozsvath, Engelbert Schucking. 2005-05-10. Active Mass Under Pressure. https://doi.org/10.1119/1.2198881

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