Test Exploration of Active Galactic Nuclei

The observations show that among the BL Lac objects,the four objects IE 0317+186,Mark 421,ON+231 and BL Lac all have the intense variations in their luminosities with greater amplitudes and shorter timescales.In this paper,it has been proved that if this phenomenon is explained by the unstability of the accretion disk of the central kerr black hqle of the BL Lac objects,then the mass of the central compact object and the size of its radiant region may be estimated by using the maximal and minimal-timescales.of the variations in luminosities and light curves of the BL Lac objects.