Control of black hole evaporation

Ahn, Doyeol, Journal of high energy physics : JHEP v.2007 no.3 , 2007, pp.021 – 021 Contradiction between Hawking’s semi-classical arguments and the string theory on the evaporation of a black hole has been one of the most intriguing problems in fundamental physics. A final-state boundary condition inside the black hole was proposed by Horowitz and Maldacena to resolve this contradiction. We point out that the original Hawking effect can also be regarded as a separate boundary condition at the event horizon for this scenario. Here, we found that the change of the Hawking boundary condition may affect the information transfer from …

Speedup of Grover’s search algorithm and closed timelike curves

Ki Hyuk Yee1, Jeongho Bang2, Paul M Alsing3, Warner A Miller4 and Doyeol Ahn6,1,4,5 Published 17 September 2020 • © 2020 IOP Publishing Ltd The quadratic reduction of query complexity of Grover’s search algorithm (GA), while significant, would not be enough to enjoy exponentially fast data searching in large-scale quantum computation. One of the ways to enhance the speedup in the framework of Grover’s algorithm is to employ a novel quantum operation, i.e., inversion against an unknown state; however, this is not possible at least in quantum theory. We thus extend the Grover algorithm assisted by closed timelike curves (CTCs), in which the unknown-state inversion is achievable …