What is the cosmic web?

Looking at the night sky, it seems that stars and galaxies are located more or less at random. It is, however, not quite. Despite the randomness, the universe is not a random mess of objects. It may seem surprising, but the Universe has a structure, consisting of massive filaments of galaxies separated by giant voids. Scientists call this the structure of the cosmic web. But why is she so weird? The answer probably lies in the processes that occurred in the first few hundred thousand years after the Big Bang.

What is the voids and galaxy filaments?

You and incredibly lucky. At least, this was an outstanding theoretical physicist Stephen Hawking. According to the scientist, even though we live on an ordinary planet that revolves around an unremarkable star, we have a chance to know the Universe. Today a map is not only closest to the Earth exoplanet, but also the entire observable Universe. And if one look on a map you feel a little dizzy, then get ready for a real ride.

Before you is a map of the observable Universe. That’s crazy, though, right?

To try to imagine the approximate scale of what is happening, let’s start the countdown from the milky Way galaxy. Our closest galactic neighbors, the Andromeda galaxy and galaxy Triangle. As well as about 50 galaxies in the Local group. Space telescope Hubble is not just pictures of these amazing inhabitants of outer space. However, one should not forget that the universe is expanding, which means that the galaxies fly apart from each other in a variety of aspects. We recently wrote about the fact that in the vastness of space, so many things happen, including the collision of three galaxies together.

So look 15 thousand galaxies in the lens of the Hubble telescope

However, in addition to galaxies in the vastness of space, there are nebulae, star clusters, galaxy clusters and even superclusters of galaxies. Some of these objects in the observable Universe has been identified by astronomers in the large-scale structure because of its incredibly large size. The largest of them extend for hundreds and billions of light years. Because of its elongated shape, these objects were called galactic filaments. These threads intertwine, fill empty space or voids (as void), as if forming a three-dimensional web. But that’s not all — the voids and galaxy filaments can form a “great wall” — a relatively flat complexes, clusters and superclusters of galaxies.

Galactic superclusters and the great wall

If there are more than 100 supercluster of thousands of galaxies, this supercluster is called Laniakea, which translated from Hawaiian means “immense heaven.” Beautiful name, isn’t it? The diameter of Laniakea reaches 500 million light years. And so you can better imagine the scale, recall that the diameter of the milky Way galaxy is about 100 thousand light years.

Laniakea and the nearest supercluster of galaxies of the Perseus-Pisces look like this

Thus, the space network consists of interconnected strands of grouped galaxies and gas, stretched across the Universe and separated by giant voids. The largest discovered to date structures is the Great wall of Hercules — Corona Borealis, which has a staggering 10 billion light-years in diameter and contains several billion galaxies. As for the voids, it is the largest void FAC, named after the astronomers Keenan, Barger and Cowie. Diameter KVS is 2 billion light years.

Overall, these features give the Universe a little frothy appearance. However, it is necessary to reduce the magnitude, this pattern disappears and the universe is like a homogeneous piece of galaxies. Astronomers have a great title for this sudden uniformity is the End of Majesty (End of Greatness). On a smaller scale, however, we can see the structure of the Universe. But how did this structure?

It all started with a Big Bang

About 14 billion years ago the Big Bang gave rise to our Universe. In the early universe are incredibly small pairs of particles and antiparticles spontaneously arise and destroy each other. Thus, space itself seemed to be in full swing. Typically, these pairs of particles destroy each other, but the rapid expansion of the early universe prevented it. With the expansion of space, these fluctuations also increased, causing differences in the density of the Universe.

Since matter attracts matter through the force of gravity, these differences explain why matter is “sticky” in some places and not in others. However, this does not fully explain the structure of the cosmic web. In the first 10-30 seconds after the Big Bang, the universe was full of plasma primary, stuck together due to the aforementioned differences. When this material was heavy, it created pressure that counteracted gravity, creating ripples, like the sound wave. Physicists call these ripples baryon acoustic oscillations. Simply put, this ripple is the product of normal matter and dark matter. As we know, dark matter is the most mysterious structure in the Universe. Overall, these and many other processes such as the interaction between ordinary and dark matter has generated a cosmic web, which is a structure of the Universe.

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