They manage to simulate gravitational quantum entanglement

Quantum gravitational entanglement simulated

Circuit executed by IBM's quantum computer, which simulates the creation of quantum entanglement through gravity. / UAM

A researcher at the Universidad Autónoma de Madrid has simulated on an IBM quantum computer the creation of quantum entanglement by means of the gravitational field. This theoretical work could help future experimental validation of gravity as a quantum force.

Quantum gravitational entanglement simulated
Circuit executed by IBM's quantum computer, which simulates the creation of quantum entanglement through gravity. / UAM

Theoretical physicist Carlos Sabin of the Autonomous University of Madrid (UAM) has carried out a simulation in a IBM quantum computer that could be useful on the way to proving that gravity is a quantum force.

Although an actual experiment has not yet been performed, this advance is a step toward a better understanding of the quantum nature of gravity.

The study, published in the journal EPJ Quantum Technologyreveals how experimental groups could use these findings to empirically verify the quantum character of the gravitational field.

Experimental groups could use the results of this simulation to empirically verify the quantum character of the gravitational field.

"While the experimental proposals to generate entanglement through gravity are still beyond our current technological capabilities, it is conceivable that this will change in a few years, says Sabin.

"This evolution would allow direct verification of the quantum aspects of gravity," he adds, "but in the meantime, I have turned to one of IBM's quantum computers to simulate these experiments. 


Towards a quantum theory of gravity

To date, we do not have a quantum theory of gravityunlike other fundamental forces such as electromagnetism. There are theoretical proposals, such as the famous string theorybut its experimental verification remains beyond the reach of current technologies.

Recently, a more modest approach has been developed which aims to simply demonstrate the quantum nature of gravitywithout the need to reveal all the underlying quantum theory.

This approach is based on the idea that, if we manage to generate quantum entanglement between systems governed by quantum physics through purely gravitational means, we may be able to confirm that the gravity is, in fact, a quantum forceeven without knowing the complete theory.

If quantum entanglement between systems governed by quantum physics is achieved through gravitational means, it could be confirmed that gravity is a quantum force.

"He entanglement is the term we use to describe certain correlations between measurement results that are only possible in quantum systems. These correlations are extremely useful for the development of new technologies, including quantum computers," explains Sabin.

As part of his research, Sabin translated the results of a specific experiment - conducted by scientists at University College London (UK) and the University of Groningen (The Netherlands) - into the language of the quantum bits (cubits) and the transformations between them (quantum logic gates). He then implemented the simulation over the Internet on a quantum computer and analyzed the results, comparing them with theoretical ideals.

"Using modern techniques to 'mitigate' experimental errors, I have found that the results obtained are practically identical to the theoretical ones. This indicates that the entanglement generated between the cubits would be equivalent to that which would have been generated by gravity between quantum systems in a real experiment," concludes the researcher.

Reference:

Sabin, C. (2023). "Digital quantum simulation of quantum gravitational entanglement with IBM quantum computers". EPJ Quantum Technology, 2023

 
Source: SINC/UAM
Octavio Alonso