Correction to: A Core-Envelope Massive Distribution with a Parabolic Density Distribution in the Core
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1 Correction to: General Relativity and Gravitation, Vol. 22, No. 7, 1990 https://doi.org/10.1007/BF00764153
The study carried out by Negi et al.  deals with the construction of a core-envelope model of static and spherical mass distribution characterized by exact solutions of Einstein’s field equations. The core of the model is described by Tolman’s VII solution  matched smoothly at the core-envelope boundary. The region of the envelope is described by Tolman’s V solution  which is finally matched to the vacuum Schwarzschild solution. The core-envelope boundary of the model is assured by matching of all the four variables—pressure (P), energy density (E) and both of the metric parameters \(\nu \) and \(\lambda \) with recourse to the computational method. However, it appears that while computing the core-envelope boundary and other parameters by using Eqs. (19)–(22) and thereafter following the expression for \(w_b\), some error occurred in the computation of Negi et al.  which has affected the results of this paper significantly. I have found that this matching can be ensured for the values of n in the range \(0 < n \le (3/4)\) and that the matching does not exist for the values of \(n > (3/4)\). The last claim is not in agreement with the claim made in the study of Negi et al.  that the matching also exists for the value of \(n = 1\) [\( u = (1/3)\)]. I have carried out this matching for the values of \(n = (1/2)\) and \(n = (3/4)\) [that is for u values = 0.25 and 0.30, respectively], and the results of this study will be presented in a separate paper. The matching for other allowed values of n in the range prescribed above can also be done likewise.