Topic

In modern systems the classical modeling paradigm using static graphs may be restrictive or oversimplifying, as the interactions among the elementary system units usually change over time in a highly dynamic manner. For example, friendships are added and removed over time in a social network and links in a communication network may change dynamically, either according to a specific known pattern (satellites following a trajectory) or in an unpredictable manner (mobile ad hoc networks). The common characteristic in all these application areas is that the system structure, i.e. graph topology, is subject to discrete changes over time. In such dynamically changing graphs the notion of vertex adjacency needs to be revisited and various graph concepts, e.g. reachability and connectedness, now crucially depend on the exact temporal ordering of the edges' presence.

A temporal graph is a graph that changes over time. Assuming discrete time and a fixed set \(V\) of vertices, a temporal graph can be viewed as a discrete sequence \(G_1, G_2, \ldots\) of static graphs, each with vertex set \(V\). Many notions and algorithms from the static case can be naturally transferred in a meaningful way to their temporal counterpart, while in other cases new approaches are needed to define the appropriate temporal notions. In particular, some problems become radically different and substantially more difficult when the time dimension is additionally taken into account.

In this one-day workshop, recent advances in the area of temporal / dynamically changing graphs will be presented, as well as some of the key challenges will be highlighted. As this research area grows and broadens, our aim is to bring together people from theoretical and practical communities of temporal graphs in order to establish new and strengthen existing links between these communities.

The topic of the workshop is of high interest and relevance to ICALP track A, as it mainly focuses on algorithms and computational complexity, but it can also straddle to parameterized complexity, structural graph theory, combinatorial optimization, distributed and mobile computing, as well as randomness in computation.

This workshop is the sequel of the six previous workshops at ICALP 2023 (in Paderborn and online, hybrid mode), ICALP 2022 (in Paris and online, hybrid mode), ICALP 2021 (online), ICALP 2020 (online), ICALP 2019 (in Patras), and ICALP 2018 (in Prague).

Some (almost half) of the presentations are given by invitation only, while the remaining presentations will be contributed talks. Everyone is welcome to register and attend (either physically or online).

Practical information

Every presentation is given 30 minutes in total, which is expected to be 20-25 minutes of talk and 5-10 minutes for questions and change-over. The presentations are grouped into four sessions (two in the morning and two in the afternoon). Details of the speakers and the schedule will be announced over time.

For those who cannot attend in person, the meeting will also be hosted on zoom. The link will be announced over time.

Workshop organizers*

• George B. Mertzios (Durham University, UK)

• Paul G. Spirakis (University of Liverpool, UK and University of Patras, Greece)

• Eleni C. Akrida (Durham University, UK)

• Viktor Zamaraev (University of Liverpool, UK)

* Partially supported by the EPSRC grants EP/P020372/1 and EP/P02002X/1, and by the EEE/CS University of Liverpool Initiative NeST.