Speaker: Prof. Runqiu Yang (Tianjin University)

Time: 14:00 on Friday, Dec. 22th, 2023

Location: Physics Building 106

Abstract: In this talk I will introduce our work about how to use energy condition constrain the number of horizons inside static black holes. It shows that the numberof horizons of static black holes can be strongly constrained by classic matters.With very general conditions, itproves that if the interior of a static black hole satisfies strong energy condition, there is at most one non-degenerated inner horizon behind the event horizon; in addition, if the event horizon is degenerated, there exists no inner horizon. This result offerssome universal restrictions on the number of horizons. Interestingly and importantly, it also suggests that classical matter not only promotes the formation of event horizon but also prevents the appearance of multiple horizons inside black holes.