Black Holes Feed On Quantum Foam, Says Cosmologist — The Physics arXiv Blog — Medium

Black Holes Feed On Quantum Foam, Says Cosmologist — The Physics arXiv Blog — Medium: “Quantum fluctuations in the form of mini black holes can couple to macroscopic black holes and allow the latter to grow exponentially...”

He says this kind of growth can easily account for the observed size of relatively young supermassive black holes. And he goes on to predict that this mechanism could allow smaller black holes to grow too. In fact, he suggests these smaller objects, which would be difficult to observe from Earth, could make up a significant fraction of the mysterious dark matter that astronomers believe the universe must contain.

...He says that this quantum feeding mechanism must apply to the supermassive black hole at the centre of our galaxy and that consequently, it must be growing at the rate of about 10^-3 solar masses per year.

How to Measure Quantum Foam With a Tabletop Experiment

How to Measure Quantum Foam With a Tabletop Experiment: Bekenstein's goal is to move the block by a distance that is about equal to the Planck length. His method is simple: zap the block with a single photon.

The photon carries a small amount of moment and consequently pushes the block as it enters the glass, giving it some momentum.  As the photon leaves the block, the block comes to rest.

So the result of the photon's passage is that it moves the block a small distance.

Bekenstein's idea is that if this distance is smaller than the Planck length, then the block cannot move and the photon cannot pass through it.

So the experiment involves measuring the number of photons that pass through the block. If the number is fewer than predicted by classical optics, then that proves the existence of quantum foam.

Physicist Discovers How To Make Quantum Foam In A Test Tube - Technology Review

Physicist Discovers How To Make Quantum Foam In A Test Tube - Technology Review: "It turns out that there is a close similarity between the way light is effected by the curvature of spacetime and the way it is influenced by the electromagnetic "space" inside a metamaterial. In fact, there is a formal mathematical analogy between these things. So the behaviour of photons inside a metamaterial is identical to their behaviour in space-time...
So his idea is to create a metamaterial in which the dielectric permittivity is just blow this critical value. Then any thermal fluctuations inside the material ought to raise the permittivity, making the material opaque in that region.
So any photons caught in that region will be trapped. 'They experience total internal reflection at any incidence angle,' says Smolyaninov.
That region is therefore an analogue of a black hole. And the fact that these black holes will spring in and out of existence as the temperature naturally fluctuates means that the metamaterial behaves like quantum foam."