Scientists are closer to being capable of detecting Hawking radiation, a mysterious thermal radiation believed to be caused by an event horizon. It is difficult to even understand the radiation concept.
A new proposal proposes creating a special type of quantum circuit that acts as a "black hole laser", simulating some properties of a real black hole. Similar to previous studies, experts could observe and study Hawking radiation in the same way as they did with real black holes.
It is quite simple. The basic principle of black holes is that they are objects that warp spacetime to the point where no wave of light can escape. You can swap spacetime for water and make it flow fast enough to cause waves to pass through too slowly. This is a very basic model.
A variety of examples may also include a "white hole" equivalent, a type of backwards-black hole in which waves can only escape but cannot enter.
Researchers propose a new material that is not found in nature. It has a structure so that the particles can move at a faster speed than the light passing through it.
Illustration of the black hole laser within the circuit. (Katayama Scientific Reports 2021).
Haruna Katayama, a Japanese physicist from Hiroshima University, says that Hawking radiation can travel back and forth between the horizons because of the metamaterial element.
The goal is to amplify the Hawking radiation sufficiently to allow it to be measured. Katayama also uses the Josephson effect, a phenomenon that creates a continuous flow without voltage.
This proposal, which uses the Josephson effect and the metamaterial, promises to go beyond any previous attempts at imagining what a blackhole laser might look like.
This circuit could possibly produce what is known as a "soliton". The research suggests that such a waveform may be localized and self-reinforcing and can hold its speed and form until external factors break it down.
Katayama says that unlike other black hole lasers, this version has a black/white hole cavity within a single soliton. Hawking radiation is then emitted outside the soliton to allow us to evaluate it.
The system would ultimately allow for a quantum correlation between two particles, one inside and one out, to be mathematically measured without the need to observe them simultaneously.
This is how Hawking radiation, also known as entangled particle pair production, is believed to be made. The discovery of it would bring us closer to a circular and unified theory of everything that ties together quantum mechanics, general relativity, and other aspects.
There are still many challenges to making this black hole laser a reality. However, if scientists can correctly configure it, it may allow us to see Hawking radiation and give us the tools we need to control it, opening up new possibilities.
Katayama says, "In the future we would like to create this system for quantum communications between distinct spacetimes using Hawking radio."
Scientific Reports published the research.