Below you will find the translation of the article “How to create a universe” by author Paul M. Sutter, published on the Space.com website. The article assumes that you are an “omnipotent chef”, what ingredients and recipes will you use to “treat” the universe?
Paul M. Sutter is an astrophysicist in the Department of Astronomy at Ohio State University and the Flatiron Institute. He is the host of the programs Ask a Spaceman and Space Radio, and is the author of the book How to Die in Space.
Do you want to decode the greatest mysteries of the universe? Let’s start by learning the basics of cosmology – the study of our entire universe.
If you want to “make” a universe, you will need two main ingredients and one additive. To create the universe as we know it today, you need about 25% dark matter and 70% dark energy. Black matter is a completely invisible form of matter that does not interact with light at all. We don’t know exactly what dark matter is made of, but we always know about its presence through its mechanism and its gravitational impact on other objects.
Astronomers map the distribution of dark matter indirectly, thanks to the gravitational force that this type of matter exerts on other objects in the universe. Image source: NASA, ESA and D. Coe (NASA JPL/Caltech and STScI) (opens in a new tab), CC BY
In addition to dark matter, you will need it in large quantities dark energy which is even more mysterious. Dark energy is the name we give to the accelerating expansion of the visible universe, or in other words, the universe is expanding faster and faster. We suspect that dark energy is involved in the vacuum of space-time. Think about it like this. Suppose you have a box containing no matter or radiation, so you think the box is empty. But in reality, the box is still filled with dark energy. However, we only suspect it, but we do not fully understand it.
In short: find enough dark energy and dark matter and you get 95% of what made up the universe for most of its history.
What about optional additives? It is ordinary material which cosmologists often call “baryonic matter”, like protons and neutrons. All forms of matter that make up atoms, molecules, people, planets, stars, galaxies are. The visible matter of the universe (ordinary matter) is not a very important component. But with this, the night sky will be brighter, so it’s worth adding.
This is what makes up the universe today: a little ordinary matter, a lot of dark matter and a lot of dark energy. Dark energy is trying to tear the universe apart, but other than that it doesn’t really participate in the day-to-day activities of the universe.
Dark matter clumps together into a complex, lattice-like pattern of enormous size calledspace network» (cosmic web). It contains spheres of dark matter spanning millions of light years. There are also some Chain (rope) hay son (filament) long dark matter, strung between the spheres. Don’t forget to mention them cosmic void (cosmic void) with almost nothing inside. But aside from being the backbone of the universe, dark matter doesn’t do much else. They are dark and don’t interact with light at all, just stay in place.
Three-dimensional simulation showing galaxies organized in the cosmic web. Photo source: V. Springel, Max-Planck Institut für Astrotrophysik, Garching bei München
Usually, small amounts of material are trapped in this dark web. Small clusters of dark matter are called Halo (halo) surrounds the galaxy. And giant blocks surround an entire cluster of galaxies. Meanwhile, the filament hosts chains of galaxies spanning light years.
The cosmic web is the largest structure discovered in nature, filling our entire visible universe (and probably more, but we can’t see any more). You may be wondering how big is the visible universe? Current estimates say it’s about 90 million light years across, but that’s only a small part of the vast universe.
The story happened before that
How did the universe reach the state we know today? How did dark matter become part of a giant cosmic web? About a hundred years ago, we discovered something astonishing, even before the discovery of dark matter: the universe is expanding.
The visible universe today contains hundreds of billions of galaxies. Photo: NASA, ESA and J. Lotz (STScI)
As the days go by, galaxies move farther and farther away from each other (in general, but there is always a possibility that two galaxies could collide). This means that the universe today is very different from the universe of the past, and even more different from the universe at the beginning. Cosmologists can travel back in time to a time when everything in the universe fit into a tiny, restricted place: 13.77 billion years ago, the entire visible universe was just the size of an apple , a peach and was hot at over a million billion degrees.
An impressive statement! How can we know something as magnificent as the universe from where we sit on Earth? We can say this because there is evidence to support it.
For example, we know that if the universe was very small in the past and is now very large, then it is clear that the universe must have been much hotter in the past (because matter compressed into smaller space must have generate stronger heat). At some point in history, the universe must have been in a plasma state, where electrons were being removed from atoms. Until a certain critical moment, the universe reached a size large enough and a temperature cold enough to form the first atoms, releasing hot, white mist-like radiation. This radiation still exists today, it is propagated throughout the universe, but it is only microwave radiation which is much weaker than before.
We can observe microwave radiation using microwave telescopes. It is in fact the largest source of light ever created in the universe. Up in the sky, every night, the legacy left by the Big Bang is left.
Yes, matter is usually responsible for releasing this type of radiation. So even though it only makes up a small part of the universe, matter still plays an extremely important role.
Original article: How to create a universe
Author: Paul M. Sutter