Extreme black holes have hair that can be combed

Black holes are considered to be one of the most mysterious things in the universe. Part of their conspiracy stems from the fact that they are in fact the simplest solutions to Einstein’s field equations of general relativity. In fact, black holes can be characterized entirely by only three physical quantities: their mass, spin, and charge. Because they have no additional “hairy” qualities to identify them, black holes are said to have “no hair”. Black holes of the same mass, spin, and charge are equal to each other.

Professor Gaurav Khanna of the University of Massachusetts Dartmouth and his former student at Rhode Island University, Dr. . In particular, the team studied exceptional black hole-2 holes that are “saturated” with maximum charge or spin that can potentially carry. They discovered that there is a quantity that can be built from a spatial time curve on a black hole horizon that is protected, and can be measured by a distant observer. Because this amount depends on how the black hole is formed, and not just on the three classical features, it violates the specificity of the black hole.

This amount constitutes “gravitational hair” and is potentially measurable by recent and upcoming gravitational wave observations, such as LIGO and LISA. This new hair formation follows the same amount of growth that was found by Angelopoulos, Eratakis and Gajik in the context of a simple “toy” model using scalar field and rounded black holes, and extending it to rotating gravitational distortions. Ones.

“This new result is surprising,” Berko said, “because black hole specific theorems are well established, and in particular their extension to black holes. There must be an assumption of the theorem that is not satisfied, to explain how.” The theorem does not apply in this case. “Indeed, the team followed the previous work by Eratakis, who discovered that the outer dislocations of extreme black holes decay, however, also do for regular black holes, some appetite fields along the event horizon. Develops indefinitely. “The specificity theorem assumes freedom of time. But the occurrence of Eratakis clearly violates the freedom of time along the event horizon. This is the loophole through which hair can come out and be combed at great distances by the gravitational wave observatory,” Burko said. . Unlike other work involving hair in black hole scaling, Berko notes that “in this work we are working with the vacuum Einstein principle, without additional dynamic fields altering the principle and which may violate the principle of strong equilibrium.”

The team used very intensive numerical similarities to generate their results. In parallel, simulations using high-end Nvidia graphics-processing-units (GPUs) with 5,000 cores each. Khanna said that each of these GPUs can calculate up to 7 trillion per second, however, despite this type of computing capacity, the simulation takes several weeks.

Provided by thesis research