Holograms are mostly used as novelty tech with a futuristic twist, but the science behind them may help us finally solve a major problem when it comes to black holes. Black holes are cosmic objects from which nothing, not even light, can escape.
The cardinal theories of physics, relativity, and quantum mechanics don’t play along well when it comes to black holes. For quantum mechanics, black holes need to hold the information of everything they have interacted with and are the sum of everything they have absorbed. For relativity, they are instead simple, smooth, and everything about them can be derived from a handful of parameters such as mass and area.
Holograms come into the fold in an attempt to reconcile these two views. Similar to how holograms are two-dimensional but appear 3D, the holographic principle is the idea that a lot more information is encoded in a state with one less dimension than we are considering, for example in 2D rather than 3D.
In a paper published in Physical Review X
, researchers from SISSA in Italy have tested the holographic principle in the context of gravity, asking if under those theoretical constraints one could make a black hole that would reconcile both quantum mechanics and relativity. And the answer appears to be yes.
"This study is only the first step towards a deeper understanding of these cosmic bodies and of the properties that characterise them when quantum mechanics crosses with general relativity,” the researchers said in a statement
The idea that black holes are like a hologram doesn’t mean they are a realistic illusion, but that while they may look simple and smooth in 3D, all the extra information required by quantum mechanics can be found when considering the object in just two dimensions. And while the study is exciting, it is still exclusively theoretical. This description might be a solution with no bearing in reality. Some evidence for or against might be uncovered soon.
“Everything is more important now at a time when observations in astrophysics are experiencing an incredible development. Just think of the observation of gravitational waves
from the fusion of black holes result of the collaboration between LIGO and Virgo or, indeed, that of the black hole made by the Event Horizon Telescope
that produced this extraordinary image,” the authors commented.
“In the near future, we may be able to test our theoretical predictions regarding quantum gravity, such as those made in this study, by observation. And this, from a scientific point of view, would be something absolutely exceptional."