Astrophysicists have devised a new way to simulate a ‘mysterious’ galactic halo of dark matter

Astrophysicists have long sought to discover dark matter, the elusive and invisible force that does not reflect or emit light but is responsible for the massive amount of all matter—about 85 percent by some estimates—in the universe.

One promising avenue of research is the concept of “fuzzy dark matter,” a hypothetical form of mysterious matter that is presumed to be composed of very light scalar particles.

The material type is known to be difficult to simulate due to its unique properties. However, scientists at the University of Zaragoza in Spain and the Institute of Astrophysics in Germany recently proposed a way to simulate the misty dark matter that forms a galactic halo.

Their method, outlined in the paper in Physical Review Lettersimproves on an algorithm introduced by the team in a previous study.

“The numerical challenge for studies focusing on hazy dark matter is that its characteristic features, granular density fluctuations in halos and collapsing filaments, are orders of magnitude smaller than any cosmic simulation box large enough to accurately capture the dynamics of the cosmic web,” explained Bodo Schwab, one of the researchers who They conducted the study, for Phys.org.

“Thus, people have for years tried to combine efficient numerical methods that capture large-scale dynamics with algorithms that require computational computation but can precisely develop these density fluctuations,” Schwab continued.

Uncover the secret of dark matter

Schwabe and his colleague, Jens C. Niemeyer, believe that only the method they have developed is currently able to successfully perform a cosmic simulation of mysterious dark matter. Using their algorithms, they said they were able to simulate the collapse of the universe’s web into threads and halos using what’s known as the “n-body method”. The n-body method breaks down the “initial density field” into small particles that evolve with the effects of gravity.

“The n-body method is a very stable, well-tested and efficient method, but it does not capture the density fluctuations of the interfering dark matter field in strings and halos,” Schwab explained. In a small sub-volume of our simulation box that tracks the center of a predefined halo, we switched to a different algorithm, known as the finite difference method, which directly develops the fuzzy darkness of the material wave function and thus can capture its interference patterns resulting in grain density fluctuations. distinctive”.

Schwabe and Niemeyer combined both the n-body method and the finite difference method, both of which are widely used but rarely combined for cosmological simulations. This upgraded the n-body particles to a state of coherent wave packets known as “Gaussian packets”, resulting in a fuzzy dark matter wave function that allowed them to run their own simulations. The researchers believe their method will help the global scientific community better understand dark matter as a whole.

Although large telescope projects such as NASA’s James Webb aim to help unravel the mysteries of dark matter and dark energy, new approaches to simulating elusive forces at gigantic scales will still be required to understand their findings in the coming years.