A new measurement of the universe confirmed this Dark energy It represents about 69% of the total.
This leaves the remaining 31% for the material; Both the natural kind – the particles and forces that make up everything we can see – and Dark mattera mysterious gravity poltergeist responsible for movements and effects that currently cannot be explained otherwise.
“Cosmologists believe that only about 20% of all matter is made up of ordinary or ‘baryonic’ matter, which includes stars, galaxies, atoms and life.” He explains Astronomer Mohamed Abdullah from the National Institute for Astronomy and Geophysics Research in Egypt and Chiba University in Japan.
“About 80% of it consists of dark matter, the mysterious nature of which is not yet known, but which may consist of some subatomic particles that have not yet been discovered.”
On the other hand, dark energy is more powerful. We also don’t know What is this?. It’s the name we give to everything that drives a car Accelerating expansion of the universeAnd there’s a lot of that out there. Repeated measurements have found that it makes up most of the matter and energy density in the universe, in an amount that tends to… ranges around 70%.
Galaxy clusters like Abell 370, shown here, can contain hundreds to thousands of gravitationally bound galaxies. (X-ray: NASA/CXC/Penn State Univ./G. Garmire; Optical: NASA/STScI)
Until now, the rate of expansion of the universe It is very difficult to determineBut there are many good reasons why scientists want to do this. Reducing the density of matter and energy in the universe could help scientists Find out what dark energy isHow it has affected the expansion of the universe so far, and what could happen in the future: the universe expanding forever, or reversing and contracting somewhat. Big crisis.
A tried-and-true way to figure out how much dark energy there is is based on galaxy clusters. This is because it consists of matter that has gathered together under the influence of gravity throughout the life of the universe, which is about 13.8 billion years.
By comparing the number of galaxies and cluster mass using numerical simulations, scientists can calculate the ratios of matter and energy.
“How did today’s galaxy clusters form from matter that collapsed over billions of years under the influence of their own gravity?” He explains According to astronomer Gillian Wilson of the University of California Merced, “the number of clusters currently observed, or the so-called ‘cluster abundance,’ is very sensitive to cosmic conditions and, in particular, to the total amount of matter.”
But since most of the mass comes from dark matter, it is difficult to measure the mass of galaxy clusters directly. Instead, the researchers identified the mass of galaxy clusters in their database, which they carefully analyzed using… GalWeight Team Coach To make sure each includes only galaxy clusters, count the number of galaxies in each. Because more massive clusters contain more galaxies, a relationship known as… Percentage of collective wealth (MMR), the researchers were able to estimate the total mass of each of their sample sets.
They then ran numerical simulations to generate clusters of galaxies, with varying proportions of dark energy and matter. The simulations were closest to the observed galaxy clusters for a universe made up of 31% matter.
This is very close (and improved) From the team’s previous effortsWhich produced a percentage of dark energy 68.5% and matter 31.5%. It also agrees very well with other measurements of the density of matter and energy in the universe, suggesting that we are very close to pinpointing it.
“We were able to make the first measurement of matter density using MRR, which is in excellent agreement with what the Planck team obtained using MRR. Cosmic microwave background radiation“, says astronomer Tomoaki Ishiyamafrom Chiba University.
“This work also demonstrates that cluster abundance is a competitive technique for constraining cosmological parameters and complements non-cluster techniques such as CMB anisotropy, Baryonic acoustic oscillations, Type Ia supernovae or Gravity lenses“.
The research was published in Astrophysical Journal.
