In astronomy, Galaxy clusters are just areas where the density of galaxies is above average and voids are areas where the density is below average. Galaxies attract each other, so the material for Galaxy clusters has to come from somewhere, and that somewhere is voids.
That and dark energy. Although this may apply for cosim super-voids and not a void in a cluster, but the expansion of space is faster in areas of space that have less mass than cosmic strings. So if someone built a ship and tried to enter a void they would have to overcome the ‘escape’ (not really but I don’t care enough to use the correct terms correctly) velocity of the galaxy, and the expanding space ahead of them.
Dark matter just makes voids more isolated from each other. Our void is still within the greater Laniakea Supercluster, but our immediate area is very sparse. The only galactic merger that the Milky Way will experience is with Andromeda in 1.5 billion years, and maybe with Traingulum a bit after. But there will be a ton happening in the Virgo Cluster next door as those galaxies are all close enough to each other that gravity is the predominant force in the region. But the galaxies in the middle of the cluster will gather towards their gravitational center, while the galaxies at the periphery of the cluster will form a “shell” of sorts. Voids are just the bubbles that remain from the gathering of clusters.
It’s basically the same reason why it’s so hard to leave Earth. You can’t just jump. Or fly in an aeroplane. You need a rocket with enough fuel. Otherwise you will fall back down again.
Saw a video about this. Apparently galactic voids are pretty hard to enter for reasons that elude my 6am brain. Something to do with gravity.
In astronomy, Galaxy clusters are just areas where the density of galaxies is above average and voids are areas where the density is below average. Galaxies attract each other, so the material for Galaxy clusters has to come from somewhere, and that somewhere is voids.
That and dark energy. Although this may apply for cosim super-voids and not a void in a cluster, but the expansion of space is faster in areas of space that have less mass than cosmic strings. So if someone built a ship and tried to enter a void they would have to overcome the ‘escape’ (not really but I don’t care enough to use the correct terms correctly) velocity of the galaxy, and the expanding space ahead of them.
Dark matter just makes voids more isolated from each other. Our void is still within the greater Laniakea Supercluster, but our immediate area is very sparse. The only galactic merger that the Milky Way will experience is with Andromeda in 1.5 billion years, and maybe with Traingulum a bit after. But there will be a ton happening in the Virgo Cluster next door as those galaxies are all close enough to each other that gravity is the predominant force in the region. But the galaxies in the middle of the cluster will gather towards their gravitational center, while the galaxies at the periphery of the cluster will form a “shell” of sorts. Voids are just the bubbles that remain from the gathering of clusters.
I think it’s to do with the combined gravity of the “strings” of galaxies, stars, etc. being far stronger than nearly nothing.
It’s basically the same reason why it’s so hard to leave Earth. You can’t just jump. Or fly in an aeroplane. You need a rocket with enough fuel. Otherwise you will fall back down again.
So a black hill.