A quasiblack hole is an object in which its boundary is situated at a surface called the quasihorizon, defined by its own gravitational radius. We elucidate under which conditions a quasiblack hole can form under the presence of matter with nonzero pressure. It is supposed that in the outer region an extremal quasihorizon forms, whereas inside, the quasihorizon can be either nonextremal or extremal. It is shown that in both cases, nonextremal or extremal inside, a well-defined quasiblack hole always admits a continuous pressure at its own quasihorizon. Both the nonextremal and extremal cases inside can be divided into two situations, one in which there is no electromagnetic field, and the other in which there is an electromagnetic field. The situation with no electromagnetic field requires a negative matter pressure (tension) on the boundary. On the other hand, the situation with an electromagnetic field demands zero matter pressure on the boundary. So in this situation an electrified quasiblack hole can be obtained by the gradual compactification of a relativistic star with the usual zero pressure boundary condition. For the nonextremal case inside the density necessarily acquires a jump on the boundary, a fact with no harmful consequences whatsoever, whereas for the extremal case the density is continuous at the boundary. For the extremal case inside we also state and prove the proposition that such a quasiblack hole cannot be made from phantom matter at the quasihorizon. The regularity condition for the extremal case, but not for the nonextremal one, can be obtained from the known regularity condition for usual black holes.
本文从多方状态方程出发，研究了各向异性压力和电磁场作用下的Einstein-麦克斯韦方程组。场方程的新的精确解是根据初等函数生成的。Feroze和Siddiqui（Gen Relativ Gravit 43：1025，2011）和Maharaj和Mafa Takisa（Gen Relativ Gravit 44：1419，2012）的不带电溶液的特殊情况被恢复。从一般的处理中，我们也得到了中性各向异性引力体的多面体的精确解。图形显示，能量密度，切向压力和各向异性的配置文件是一致的，与早期的治疗，这表明在描述相对论性致密星的相关性。
