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Abstract. Power-law distributions of landslides and rockfalls observed under various conditions suggest a relationship of mass movements to self-organized criticality (SOC). The exponents of the distributions show a considerable variability, but neither a unique correlation to the geological or climatic situation nor to the triggering mechanism has been found. Comparing the observed size distributions with models of SOC may help to understand the origin of the variation in the exponent and finally help to distinguish the governing components in long-term landslide dynamics. However, the three most widespread SOC models either overestimate the number of large events drastically or cannot be consistently related to the physics of mass movements. Introducing the process of time-dependent weakening on a long time scale brings the results closer to the observed statistics, so that time-dependent weakening may play a major part in the long-term dynamics of mass movements.

Abstract
A consideration of non-classical logic in terms of classical one allows us to show a role of designated truth values. In this way we show that our version of non-classical many-valued logic can be based on the structure of genetic code.

The oldest answered question in the social sciences is 'Why do societies collapse?'. I advance a theory of the collapse of societies that is based on self-organized criticality, which is a nonlinear process that produces sudden shifts and fractal patterns in historical time series. More generally, I conjecture that weak, self-organized criticality is ubiquitous in human systems. If this conjecture is correct, it would not only explain the source of total societal collapses but the pattern of most other sorts of human calamities and even the frequency distribution of many mundane day-to-day events.

The concept of 'self-organized criticality' (SOC) has been applied to a variety of problems, ranging from population growth and traffic jams to earthquakes, landslides and forest fires. The technique is now being applied to a wide range of phenomena in astrophysics, such as planetary magnetospheres, solar flares, cataclysmic variable stars, accretion disks, black holes and gamma-ray bursts, and also to phenomena in galactic physics and cosmology. Self-organized Criticality in Astrophysics introduces the concept of SOC and shows that, due to its universality and ubiquity, it is a law of nature. The theoretical framework and specific physical models are described, together with a range of applications in various aspects of astrophyics. The mathematical techniques, including the statistics of random processes, time series analysis, time scale and waiting time distributions, are presented and the results are applied to specific observations of astrophysical phenomena.

Abstract: One of the challenges of monitoring political mobilization on social media is the setting of formalized mobilization criteria to identify early symptoms of political mobilization across different groups. We propose and test a tool for identifying groups that display a high level of political mobilization. This tool is based on the hypothesis that strong engagement of users in group activities and discussions is common to groups in a state of self-organized criticality (SOC). An attribute of SOC, known as pink noise, can be observed in time series. To test this hypothesis, we sourced data on activity in 200 Facebook groups in France and Germany.Keywords: self-organized criticality, pink noise, social media, political mobilization***La théorie de la criticité auto-organisée aide-t-elle à identifier la mobilisation politique sur les réseaux sociaux ?Résumé: L'une des difficultés de la surveillance de la mobilisation politique sur les réseaux sociaux consiste en la définition des critères de formalisation de ces mouvements afin d'identifier les premiers symptômes de mobilisation politique sur les réseaux sociaux. Nous proposons et testons un outil capable d'identifier des groupes qui affichent un fort taux de mobilisation politique. Cet outil repose sur l'hypothèse selon laquelle un fort niveau d'engagement des utilisateurs dans les activités et discussions du groupe est commun aux groupes dans un état de criticité auto-organisée (SOC). L'une des particularités de la SOC, connue sous le nom de pink noise (bruit rose), peut être observée dans les séries temporelles. Afin de tester cette hypothèse, nous avons récolté des statistiques dans 200 groupes Facebook en France et en Allemagne.Mots-clés: criticité auto-organisée, bruit rose, réseaux sociaux, mobilisation politique

The nonlinear dynamical process of self-organized criticality provides a new 'theory of history' that explains a number of unresolved anomalies: Why are the really big events in human history usually unpredictable? Why is it impossible to anticipate sudden political, economic, and social changes? Why do distributions of historical data almost always contain a few extreme events that seem to have had a different cause from all the rest? Why do so many of our 'lessons of history' fail to predict important future events? As people, organizations, and nations become increasingly sensitive to each other's behavior, trivial occurrences sometimes propagate into sudden changes. Such events are unpredictable because in the self-organized criticality environment that characterizes human history, the magnitude of a cause often is unrelated to the magnitude of its effect.

Adopting a particular non-linear perspective resolves numerous paradoxes about collective political behaviour. Self-organized criticality occurs if the sensitivity of individuals or groups to each other's actions increases with the passage of time, and, therefore, sudden changes may occur as cascades. In this way scandals, betrayals, miscalculations and other seemingly insignificant actions can sometimes cause cabinet dissolutions, strikes, riots, electoral landslides, wars and a multitude of other phenomena that, until now, have seemed to have had nothing in common.

Adopting a particular non-linear perspective resolves numerous paradoxes about collective political behaviour. Self-organized criticality occurs if the sensitivity of individuals or groups to each other's actions increases with the missage of time, and, therefore, sudden changes may occur as cascades. In this way scandals, betrayals, miscalculations and other seemingly insignificant actions can sometimes cause cabinet dissolutions, strikes, riots, electoral landslides, wars and a multitude of other phenomena that, until now, have seemed to have had nothing in common. (British Journal of Political Science / FUB)