A new algorithm for anisotropic solutions
نویسندگان
چکیده
We establish a new algorithm that generates a new solution to the Einstein field equations, with an anisotropic matter distribution, from a seed isotropic solution. The new solution is expressed in terms of integrals of an isotropic gravitational potential; and the integration can be completed exactly for particular isotropic seed metrics. A good feature of our approach is that the anisotropic solutions necessarily have an isotropic limit. We find two examples of anisotropic solutions which generalise the isothermal sphere and the Schwarzschild interior sphere. Both examples are expressed in closed form involving elementary functions only. Permanent address: Department of Mathematics & Computer Science, National University of Lesotho, Roma 180, Lesotho; eMail: [email protected] Author for correspondence; email: [email protected]; fax: +2731 26
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