禁漫天堂

鈥淣early extreme black holes attempt to grow hair鈥�

The black holes of Einstein鈥檚 theory of relativity can be described by three parameters: their mass, spin angular momentum, and electric charge. Since two extreme black holes that share these parameters cannot be distinguished, regardless of how they were made, black holes are said to 鈥渉ave no hair鈥�: they have no additional attributes that can be used to tell them apart. 

Physics Professor Gaurav Khanna and Professor Lior Burko of Georgia Gwinnett College  that highlights how they are able to take measurements to discover a black hole鈥檚 hair.

Khanna and Burko used very intensive numerical simulations to generate their results. The simulations involved using dozens of the highest-end Nvidia graphics-processing-units (GPUs) with over 5,000 cores each, in parallel. 鈥淓ach of these GPUs can perform as many as 7 trillion calculations per second; however, even with such computational capacity the simulations look many weeks to complete,鈥� said Khanna.

The team showed that for extreme black holes, hair is a transient behavior. At first, they behave as extreme black holes would, but eventually they behave as regular, non-extreme black holes do. Burko summarized the result, saying, 鈥淣early extreme black holes that attempt to regrow hair will lose it and become bald again.鈥� The team also discusses the observational feature with gravitational waves observatories such as LIGO/VIRGO or LISA which found the smoking-gun detection of nearly extreme black holes.

The research was partially funded by the National Science Foundation and the Office of Naval Research. Computational resources of 禁漫天堂鈥檚 Center for Scientific Computing & Visualization Research were utilized for the research work. The Center promotes the mission of 禁漫天堂 by providing undergraduate and graduate students with high quality discovery-based educational experiences that transcend the traditional boundaries of academic field or department and foster collaborative research in the computational sciences within the University and with researchers at other universities, National Labs, and industry. Khanna serves as the Director of the Center.