Networks in the Natural World: Formation of the Universe
When I think of networks, my mind tends to picture large social media graphs with clusters of nodes, interconnected with lines to represent friendships between certain individuals. However, this same phenomenon of a network can be found naturally outside of this representation. Astronomers have known about a cosmic web of filaments connecting all the galaxies in the universe for some time, but until recently, they have not been able to physically see the structure of this network. According to the articles linked below, after the Big Bang, highly ionized gases and dark matter formed clusters spanning the entire universe. Some clusters contained more matter than others, eventually resulting in the formation of many different celestial structures such as “stars, galaxies, and galactic clusters”. As noted from the article written by The Daily Galaxy, “’The filaments are like bridges connecting the denser regions in the cosmic web’”, and astronomers have found that galaxies in the cosmic web have a much higher chance of forming stars, and it seems that the evolution of galaxies can be accelerated through connections from filaments.
In relation to topics discussed in class, it is clear that there are many similarities between the networks our minds tend to think of (social networks, the brain, etc), and those found in the natural world. For an example, let’s use a social network such as Facebook, and define a cluster of people as having strong ties with one another, and any ties connecting clusters would act as “bridges” connecting two groups of people. We can already see that the cosmic web behaves in a very similar fashion. The clusters in this situation would represent galaxies, and instead of the nodes representing people, nodes would instead define stars, clouds of gas, and other celestial bodies. The filaments as described above would serve two functions: they would act as “bridges” by connecting galaxies together, as well as connect the internal nodes within each cluster together.
Going a step further, we can relate forming friendships as seen through the social media example, to the formation of stars in a particular galaxy. Looking at the social media example, individuals in clusters tend to be comprised of a distinct friend group – have similar interests, ideas, etc. – and if person A is a mutual friend of many people in a cluster, it is very likely that person A will be included in that friend group. Similarly, galaxies in the universe are not all identical, and it can be inferred that the nodes within galaxies – i.e stars, other celestial bodies, etc. – have a certain “flavor” that makes them unique to other clusters, but similar with each other. As the filaments between galaxies allow for the formation of new celestial bodies, the growth of a galaxy cluster by the addition of a star is very similar to the growth of a friend group by the introduction of a mutual friend since in both situations, the corresponding node being added to the particular cluster is a representative of that cluster – i.e shares many similarities with the other nodes.
Through these articles, it is clear that the idea of a network is not necessarily something that needs to be based on technology, but rather it is an abstract idea that can be applied to many different facets of life; including the universe we all live in today.
Links:
http://io9.com/our-first-glimpse-of-the-web-that-connects-all-galaxies-1505762919