While these findings apply primarily to the analog black hole they created, theoretical studies could help to confirm if they can also be applied to real black holes. Overall, the findings appear to confirm that the radiation emitted by black holes is stationary, as predicted by Hawking. 'We thus took 97,000 repetitions of the experiment a total of 124 days of continuous measurement.' 'We had to collect a lot of data to see these correlations,' Steinhauer said. Once they identified these pairs of sound waves, the researchers tried to determine whether there were so-called correlations between them. When trying to identify the Hawking radiation emitted by the analog black hole they created, Steinhauer and his colleagues thus looked for similar pairs of sound waves, one coming out of the black hole and one moving into it. Hawking radiation is composed of pairs of photons (i.e., light particles): one emerging from a black hole and another falling back into it. That's what we wanted to confirm in our study, and we did.' 'Hawking suggested that black holes are just like regular stars, which radiate a certain type of radiation all the time, constantly. 'A black hole is supposed to radiate like a black body, which is essentially a warm object that emits a constant infrared radiation (i.e., black body radiation),' Steinhauer said. In their new study, they set out to investigate whether the radiation emitted by their black hole is also stationary (i.e., if it remains constant over time). In one of their previous studies, Steinhauer and his colleagues were able to confirm this prediction in their artificial black hole. This process was repeated many times, for months.Īccording to Hawking's predictions, the radiation emitted by black holes is spontaneous. To observe its evolution over time, they thus had to produce the black hole, take a picture of it and then create another one.

Every time the researchers took a picture of it, the black hole was destroyed. The artificial black hole created by Steinhauer and his colleagues was approximately 0.1 millimeters long and was made of a gas composed of 8000 rubidium atoms, which is a relatively low number of atoms. Yet this radiation starts from nothing, comes out, and goes towards Earth.' That is really weird because there's nothing there it's empty space. 'Hawking radiation starts just outside the event horizon, where light can barely escape. 'If you go inside the event horizon, there's no way to get out, even for light,' Jeff Steinhauer, one of the researchers who carried out the study, told. More specifically, they examined whether the equivalent of Hawking radiation in an 'artificial black hole' created in a laboratory setting was stationary. Researchers at Technion- Israel Institute of Technology have recently carried out a study aimed at testing Hawking's theoretical predictions. According to his predictions, this radiation is spontaneous (i.e., it arises from nothing) and stationary (i.e., its intensity does not change much over time). Theoretical physicist Stephen Hawking predicted that while nothing can escape from within them, black holes spontaneously emit a limited amount of light, which is known as Hawking radiation.

Black hole removal