ABSTRACT
Physical networks are made of nodes and links that are physical objects embedded in a geometric space. Understanding how the mutual volume exclusion between these elements affects the structure and function of physical networks calls for a suitable generalization of network theory. Here, we introduce a network-of-networks framework where we describe the shape of each extended physical node as a network embedded in space and these networks are bound together by physical links. Relying on this representation, we introduce a minimal model of network growth and we show for a general class of physical networks that volume exclusion induces heterogeneity in both node volume and degree, with the two becoming correlated. These emergent properties strongly affect the dynamics on physical networks: by calculating their Laplacian spectrum as a function of the coupling strength between the nodes we show that degree-volume correlations suppress the role of hubs as early spreaders in diffusive dynamics. We apply the network-of-networks framework to describe several real systems and find properties analog to the minimal model networks. The prevalence of these properties points towards general growth mechanisms that do not depend on the specifics of the systems.
ABSTRACT
UNLABELLED: Superior canal dehiscence is a rare syndrome. The symptoms consist of hearing loss, dizziness and autophonia. The patient can be cured with surgery. A 28 year old woman went to several doctors for several months due to diminished hearing, dizziness and autophonia. The symptoms got worse. A work-up led to the diagnosis of superior canal dehiscence in the left ear. She underwent surgery and her symptoms improved. A latency in diagnosis is expected as the syndrome is rare. It's important to think of superior canal dehiscence when patients complain of these symptoms. KEY WORDS: superior canal dehiscence, autophonia, dizziness, hearing deficit. Correspondence: Bryndis Baldvinsdottir, bryndisbaldvins@gmail.com.