Author: cxdig

Anticipating the global redistribution of people and property

Marten Scheffer, W. Neil Adger, Stephen R. Carpenter, Carl Folke, Tim Lenton, Gaia Vince, Frances Westley, Chi Xu

One Earth VOLUME 7, ISSUE 7, P1151-1154, JULY 19, 2024

Climate change will worsen conditions for people in the Global South, while conditions in large parts of the North will improve. Migration seems an effective adaptation strategy. However, making that a win-win for migrants and receiving communities requires revision of the food system, rules for mobility, and strategies for social integration.

Read the full article at: www.cell.com

Antifragility in complex dynamical systems

Cristian Axenie, Oliver López-Corona, Michail A. Makridis, Meisam Akbarzadeh, Matteo Saveriano, Alexandru Stancu & Jeffrey West
npj Complexity volume 1, Article number: 12 (2024)

Antifragility characterizes the benefit of a dynamical system derived from the variability in environmental perturbations. Antifragility carries a precise definition that quantifies a system’s output response to input variability. Systems may respond poorly to perturbations (fragile) or benefit from perturbations (antifragile). In this manuscript, we review a range of applications of antifragility theory in technical systems (e.g., traffic control, robotics) and natural systems (e.g., cancer therapy, antibiotics). While there is a broad overlap in methods used to quantify and apply antifragility across disciplines, there is a need for precisely defining the scales at which antifragility operates. Thus, we provide a brief general introduction to the properties of antifragility in applied systems and review relevant literature for both natural and technical systems’ antifragility. We frame this review within three scales common to technical systems: intrinsic (input–output nonlinearity), inherited (extrinsic environmental signals), and induced (feedback control), with associated counterparts in biological systems: ecological (homogeneous systems), evolutionary (heterogeneous systems), and interventional (control). We use the common noun in designing systems that exhibit antifragile behavior across scales and guide the reader along the spectrum of fragility–adaptiveness–resilience–robustness–antifragility, the principles behind it, and its practical implications.

Read the full article at: www.nature.com

Improving the controllability robustness of complex temporal networks against intelligent attacks

Qian Zhang, Peyman Arebi
Journal of Complex Networks, Volume 12, Issue 4, August 2024, cnae027,

The main goal of controllability network methods on complex temporal networks is to control all nodes with the minimum number of control nodes. Real-world complex temporal networks are faced with many errors and attacks that cause the network structure to be changed in some way so that the controllability processes are disturbed and after that, the controllability robustness of the network decreases. One of the most important attacks on complex temporal networks is intelligent attacks. In this paper, the types of intelligent attacks and their destructive effects on the controllability of complex temporal networks have been investigated. In order to increase the controllability robustness of the network against intelligent attacks, a novel graph model and strategies have been proposed on complex dynamic graph by adding new control nodes or adding new links to the network so that the network is protected against intelligent attacks. The results of simulation and comparing them with conventional methods demonstrate that the proposed node addition strategy has performed better than other methods and the improvement rate in terms of execution time is 60%. On the other hand, the proposed immunization strategy by adding links has kept the network controllable with a smaller number of links (38%) and less execution time (52%) compared to other methods.

Read the full article at: academic.oup.com

Cell–Cell Interactions: How Coupled Boolean Networks Tend to Criticality

Michele Braccini, Paolo Baldini, Andrea Roli

Artificial Life

Biological cells are usually operating in conditions characterized by intercellular signaling and interaction, which are supposed to strongly influence individual cell dynamics. In this work, we study the dynamics of interacting random Boolean networks, focusing on attractor properties and response to perturbations. We observe that the properties of isolated critical Boolean networks are substantially maintained also in interaction settings, while interactions bias the dynamics of chaotic and ordered networks toward that of critical cells. The increase in attractors observed in multicellular scenarios, compared to single cells, allows us to hypothesize that biological processes, such as ontogeny and cell differentiation, leverage interactions to modulate individual and collective cell responses.

Read the full article at: direct.mit.edu

Imitation versus serendipity in ranking dynamics

Federica De Domenico , Fabio Caccioli , Giacomo Livan , Guido Montagna and Oreste Nicrosini

Royal Society Open Science, July 2024 Volume 11 Issue 7

Participants in socio-economic systems are often ranked based on their performance. Rankings conveniently reduce the complexity of such systems to ordered lists. Yet, it has been shown in many contexts that those who reach the top are not necessarily the most talented, as chance plays a role in shaping rankings. Nevertheless, the role played by chance in determining success, i.e. serendipity, is underestimated, and top performers are often imitated by others under the assumption that adopting their strategies will lead to equivalent results. We investigate the tradeoff between imitation and serendipity in an agent-based model. Agents in the model receive payoffs based on their actions and may switch to different actions by either imitating others or through random selection. When imitation prevails, most agents coordinate on a single action, leading to non-meritocratic outcomes, as a minority of them accumulate the majority of payoffs. Yet, such agents are not necessarily the most skilled ones. When serendipity dominates, instead, we observe more egalitarian outcomes. The two regimes are separated by a sharp transition, which we characterize analytically in a simplified setting. We discuss the implications of our findings in a variety of contexts, ranging from academic research to business.

Read the full article at: royalsocietypublishing.org