Network theory

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For the social sciences use of network theory, see Social network.

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Network theory is a subject within applied mathematics and physics, and coincides with graph theory. It has application in a varied range of disciplines including computer science, biology, economics, and sociology. Network theory concerns itself with the study of graphs as a representation of either symmetric relations or, more generally, of asymmetric relations between discrete objects. Typically, the graphs of concern in network theory are complex networks, examples of which include the World Wide Web, the Internet, gene regulatory networks, metabolic networks, social networks, epistemological networks, etc. See list of network theory topics for the scope of the area.

1 Spread of content in networks
2 See also
3 Notes and references
4 External links

[edit] Spread of content in networks

Content in a complex network can spread via two major methods: conserved spread and non-conserved spread. ^[1] In conserved spread, the total amount of content that enters a complex network remains constant as it passes through. The model of conserved spread can best be represented by a pitcher containing a fixed amount of water being poured into a series of funnels connected by tubes (Figure 1). Here, the pitcher represents the original source and the water is the content being spread. The funnels and connecting tubing represent the nodes and the connections between nodes, respectively. As the water passes from one funnel into another, the water disappears instantly from the funnel that was previously exposed to the water. In non-conserved spread, the amount of content changes as it enters and passes through a complex network. The model of non-conserved spread can best be represented by a continuously running faucet running through a series of funnels connected by tubes (Figure 2). Here, the amount of water from the original source is infinite. Also, any funnels that have been exposed to the water continue to experience the water even as it passes into successive funnels. The non-conserved model is the most suitable for explaining the transmission of most infectious diseases.