Perhaps we can learn more about the hypothetically enigmatic radiation emitted by the real black hole by studying a new type of black hole analog.
The equivalent of Hawking radiation, particles created from disturbances in the quantum fluctuations caused by the black hole’s rupture in spacetime, has been discovered by a team of physicists using a chain of atoms in a single file to imitate the event horizon of a black hole.
According to them, this has the potential to reconcile two currently incompatible cosmological frameworks: the general theory of relativity, which describes gravity as a continuous field known as spacetime, and quantum mechanics, which describes the behavior of discrete particles using the mathematics of probability.
These two seemingly incompatible theories need to reconcile their differences in order to provide a universally applicable theory of quantum gravity.
Here enter black holes, arguably the most peculiar and extreme objects in the cosmos. Extremely dense, no known speed in the Universe can overcome the gravitational pull of a black hole unless the item is far enough away from its center of mass. Not even the speed of light!
The event horizon is the variable distance from a black hole that prevents anything from falling in. Nothing returns to tell us what happens to an object once it passes its border, so we are left to speculate. Nonetheless, Stephen Hawking postulated in 1974 that the event horizon causes a form of radiation very similar to thermal radiation by interrupting quantum fluctuations.
If Hawking radiation does exist, it is currently too weak for detection. It may be impossible to extract it from the shrieking static of the cosmos. However, by simulating black holes in controlled environments, we may investigate its properties.
While others have attempted this before, Lotte Mertens and her team from the University of Amsterdam in the Netherlands have taken it to a new level.
To ‘jump’ from one location to another, electrons followed a line of atoms in a single dimension. The researchers were able to make these qualities disappear by adjusting the ease with which electrons can hop from one state to another, effectively generating an event horizon that disrupted the wave-like behavior of the electrons.
When a portion of the chain was stretched beyond the event horizon, the temperature rise caused by the artificial event horizon was found to be consistent with theoretical predictions for a black hole analog system.
Particles that cross the event horizon get entangled with each other, which may play a crucial role in producing Hawking radiation.
Hawking radiation was only found to be thermal in simulations if the initial conditions mimicked a ‘flat’ spacetime with a specific range of hop amplitudes. This indicates that Hawking radiation might only be thermal under certain conditions and whenever there is a change in the warp of space-time as a result of gravity.
Although the model’s implications for quantum gravity remain unknown, it does provide a technique to investigate the birth of Hawking radiation free from the chaotic dynamics that accompany black hole creation. The researchers claimed that due to its ease of use, it could be implemented in a variety of different experimental configurations.