Scientists have revealed that hologram theory may be true in "realistic models" of the universe.
The "holographic principle" asserts that a mathematical description of the universe actually requires one fewer dimension than it seems. What has been perceived as three dimensional might just be the image of two dimensional processes on a huge cosmic horizon.
Results obtained by scientists at TU Wien (Vienna) now suggested that the holographic principle even holds in a flat spacetime.
Everybody knows holograms from credit cards or banknotes. They are two dimensional, but to human eye they appear three dimensional. The universe could behave quite similarly.
Daniel Grumiller (TU Wien) said that in 1997, the physicist Juan Maldacena proposed the idea that there was a correspondence between gravitational theories in curved anti-de-sitter spaces on the one hand and quantum field theories in spaces with one fewer dimension on the other.
Gravitational phenomena are described in a theory with three spatial dimensions, the behavior of quantum particles is calculated in a theory with just two spatial dimensions - and the results of both calculations can be mapped onto each other.
It was like finding out that equations from astronomy textbook could also be used to repair a CD-player. But this method has proven to be very successful. More than ten thousand scientific papers about Maldacena's "AdS-CFT-correspondence" have been published to date.
Grumiller has suspected for quite some time that a correspondence principle could also hold true for our real universe. To test this hypothesis, gravitational theories have to be constructed, which do not require exotic anti-de-sitter spaces, but live in a flat space. For three years, he and his team at TU Wien (Vienna) have been working on that, in cooperation with the University of Edinburgh, Harvard, IISER Pune, the MIT and the University of Kyoto.
When quantum particles are entangled, they cannot be described individually. They form a single quantum object, even if they are located far apart. There is a measure for the amount of entanglement in a quantum system, called "entropy of entanglement."
Together with Arjun Bagchi, Rudranil Basu and Max Riegler, Grumiller managed to show that this entropy of entanglement takes the same value in flat quantum gravity and in a low dimension quantum field theory.
This however, does not yet prove that humans live in a hologram, but apparently there is growing evidence for the validity of the correspondence principle in the universe.
The study is published in the journal Physical Review Letters.
