White Paper 15, Tensor Representations of ActivityPub Networks

Open Risk White Paper 15: Tensor Representations of ActivityPub Networks

In this third Open Risk White Paper on Connecting the Dots we explore representations of online communication networks that are organized according to the ActivityPub protocol. We discuss the main relevant features of the protocol and the broader application ecosystem around it that shapes emerging online network topologies. We develop a stylized description of ActivityPub compliant networks as a mathematical multilayer network. Tensor representations of such complex graphs generalize the more familiar matrix algebra tools and can be useful in various ways: On the one hand they help empirical work in analyzing the characteristics of such networks, on the other they enable simulating and exploring network behavior.

Structure of the White Paper

  • In this Introduction section we place the white paper in the context of contemporary developments around online networks and motivate the need for mathematical representations to help better understand growing information flows.
  • Section 2 summarizes the technical specification of ActivityPub, focusing on the elements that are important for establishing network representations and mathematical graphs.
  • Section 3 illustrates concretely how ActivityPub networks can be modeled using classic (simple) graph structures. This is an important preliminary step before we discuss more elaborate network models.
  • Finally, Section 4 covers the concept of multi-layer networks and the associated tensor representations in the context of ActivityPub network patterns.


OpenRiskWP15_020224 PDF


 author = {P. Papadopoulos},
 year = {2024},
 note = {\href{https://www.openriskmanagement.com/wp-content/uploads/2024/02/OpenRiskWP15_020224.pdf}{Download URL}},
 title = {{Open Risk WP15: Connecting the Dots: Tensor Representations of ActivityPub Networks}},
 journal = {Open Risk White Papers}