Bounds on 2m/r for static perfect fluids
نویسنده
چکیده
For spherically symmetric relativistic perfect fluid models, the well-known Buchdahl inequality provides the bound 2M/R 6 8/9, where R denotes the surface radius and M the total mass of a solution. By assuming that the ratio p/ρ be bounded, where p is the pressure, ρ the density of solutions, we prove a sharper inequality of the same type, which depends on the actual bound imposed on p/ρ. As a special case, when we assume the dominant energy condition p/ρ 6 1, we obtain 2M/R 6 6/7. ∗ Electronic address: [email protected]
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