A new study suggests that dark matter interacts with gravity non-locally

A new SISSA study suggests that dark matter interacts with gravity in non-local ways, challenging traditional theories and offering new insights into the nature of dark matter. Using fractional calculus, the researchers found that this nonlocal interaction more accurately describes the motion of stars, especially in small galaxies.

Isaac Newton described his theory of gravity as a force that acts instantly in space: a planet immediately feels the effects of another astronomical object, regardless of the distance between them. This aspect inspired Einstein to create the famous theory of general relativity, in which gravity becomes a local deformation of space-time.

The locality principle states that an object is directly influenced only by its environment: distant objects cannot communicate instantly, only what is here and now counts. However, in the last century, with the birth and development of quantum mechanics, physicists discovered that non-local phenomena not only exist but are fundamental to understanding the nature of reality.

Now, a new study from SISSA – Scuola Internazionale Superiore di Studi Avanzati, recently published in EL Revista de Astrofísica, suggests that dark matter, one of the most mysterious components of the Universe, interacts with gravity in a non-local way. According to the authors, the Ph. For students Francesco Benetti and Giovanni Gandolfi, as well as their supervisor Andrea Lapi, this discovery could offer a new perspective on the still unclear nature of dark matter.

Dark matter is a fundamental component of nature: it is responsible for the formation of the structures we see in the Universe today and surrounds the luminous matter of galaxies, thus contributing to the movement of the stars we see in the sky. However, the nature of dark matter, including its interaction with gravity in small galaxies, remains a mystery.

“Over the past decades, the scientific community has made great efforts to understand these enigmatic phenomena, but many questions remain unanswered. To explore the nature of dark matter and its interaction with gravity, a new approach might be needed,” the study authors explain. New SISSA research has explored precisely this fascinating pathway.

The study proposes a new model of non-local interaction between the dark matter of a galaxy and gravity: “It is as if all the matter in the universe tells the dark matter of a galaxy how to move,” say the authors.

Fractional calculus, a mathematical tool first developed in the 17th century and recently used in various fields of physics, was used to model this non-locality. The power of this calculation has never before been tested in astrophysics.

“We wondered if fractional calculus could be the key to understanding the mysterious nature of dark matter and its interaction with gravity, and surprisingly, experimental results in thousands of galaxies of different types showed that the new model more accurately describes the movement of the stars than that. of stars. to the standard theory of gravity,” the authors explain.

This non-locality seems to arise as a collective behavior of dark matter particles within a confined system, being particularly relevant in small galaxies. A deeper understanding of this phenomenon could bring us closer to what dark matter really is.

“However, many unanswered questions remain,” the authors note. “How exactly does non-locality arise? What are its implications within larger structures, such as galaxy clusters, or in the phenomenon of gravitational lensing, which makes it possible to observe distant celestial objects?

Furthermore, it will be necessary to reconsider the standard model of cosmology considering this new mechanism.

More studies will be done to explore all of these implications and more. We would not be surprised to find that the newly proposed non-locality could answer other unresolved questions about the Universe.

Advances in understanding the nature of dark matter represent an important step towards a better understanding of our Universe. Ongoing research continues to provide new insights and bring us closer to a comprehensive understanding of the phenomena around us.

Source: “Dark matter in split gravity. I. Galactic-Scale Astrophysical Proofs” by Francesco Benetti, Andrea Lapi, Giovanni Gandolfi, Paolo Salucci, and Luigi Danese, May 31, 2023, The Journal of Astrophysics.
DOI: 10.3847/1538-4357/acc8ca