Local universe skeleton created
The existence of dark matter, which occupies about 85% of the
entire Universe, has not been proven today. At the same time,
more and more scientists have no doubt that dark matter does
exist. This situation can be compared with gravitational waves,
the existence of which Albert Einstein predicted, but they were
discovered several years ago. Although it is impossible to directly
observe dark matter, since it does not enter into electromagnetic
interaction with photons, it is a generally accepted concept.
Scientists have made many conclusions about the existence and
behavior of dark matter by observing its gravitational influence
on other space objects.
Cosmologists believe that dark matter serves as the filamentous
skeleton of the cosmic web, which in turn constitutes the
large-scale structure of the Universe, partially controlling the
movement of galaxies and other cosmic systems. Another difficult
task is the direct measurement of the distribution of dark matter
in our local universe, so in the course of the work astrophysicists
used artificial intelligence to create a new map.
The "local universe", into which we are entering, is an area with
a radius of about 1 billion light years, where galaxies and
associated space objects "are essentially frozen in their present
configurations," and the effects of cosmic evolution are negligible
- astronomers explain.
According to (
https://bit.ly/302zBL7) Big Think, one of the authors
of the scientific work Donghui Jong, assistant professor of
astronomy and astrophysics at the University of Pennsylvania, it is
much easier to study the distribution of dark matter in the most
distant objects, since they accurately reflect the incredibly
distant past our universe. So, the space web maps created earlier
were based on simulating the evolution of the Universe 13.8 billion
years ago. These efforts required a huge amount of computation and,
in fact, did not provide an accurate idea of the local universe,
which prompted researchers to develop a new approach.
The AI was trained to simulate galaxies similar to the Milky Way
using (
https://bit.ly/3lJCCaJ) Illustris-TNG, an ongoing series of
simulations featuring galaxies, dark matter, gases and other matter.
As the authors of the scientific work explained
(
https://bit.ly/3rJIXXE) to journalists, if you enter specific
information into the model, it will be able to fill in the gaps based
on already processed data. Scientists additionally confirmed the
mapping by applying it to real local data of galaxies from the
Cosmicflows-3 catalog, which contains information on the distances
of almost 18 thousand galaxies.
The map obtained by the researchers is amazing. For the first time
in history, it was possible to consider the main structures in the local
Universe, including the Milky Way. Astrophysicists have also
described nearby galaxies and a "local void" - a nearby region
of empty space. Moreover, the map allowed scientists to discover
new structures. Thus, astrophysicists can "ask" a computer to
develop a map for billions of years to see what will happen in the
local universe. What's more, they can now create a new model to
literally take a virtual journey back in time.
