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Cross-checking different sources of mobility information

The pervasive use of new mobile devices has allowed a better characterization in space and time of human concentrations and mobility in general. Besides its theoretical interest, describing mobility is of great importance for a number of practical applications ranging from the forecast of disease spreading to the design of new spaces in urban environments. While classical data sources, such as surveys or census, have a limited level of geographical resolution (e.g., districts, municipalities, counties are typically used) or are restricted to generic workdays or weekends, the data coming from mobile devices can be precisely located both in time and space. Most previous works have used a single data source to study human mobility patterns. Here we perform instead a cross-check analysis by comparing results obtained with data collected from three different sources: Twitter, census and cell phones. The analysis is focused on the urban areas of Barcelona and Madrid, for which data of the three types is available. We assess the correlation between the datasets on different aspects: the spatial distribution of people concentration, the temporal evolution of people density and the mobility patterns of individuals. Our results show that the three data sources are providing comparable information. Even though the representativeness of Twitter geolocated data is lower than that of mobile phone and census data, the correlations between the population density profiles and mobility patterns detected by the three datasets are close to one in a grid with cells of 2x2 and 1x1 square kilometers. This level of correlation supports the feasibility of interchanging the three data sources at the spatio-temporal scales considered.


Cross-checking different sources of mobility information
Maxime Lenormand, Miguel Picornell, Oliva G. Cantu-Ros, Antonia Tugores, Thomas Louail, Ricardo Herranz, Marc Barthelemy, Enrique Frias-Martinez, Jose J. Ramasco

http://arxiv.org/abs/1404.0333

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"The Science of Success" Special Issue | Advances in Complex Systems

The increasing availability of digital data on human activities has led to the emergence of computational social science, a research field at the interface of computer science, mathematical modeling and social sciences. Among the concepts that have attracted much attention, we find "success". The premise of a science of success rests on observing that a difference exists between performance and success: Performance, representing the totality of objectively measurable achievements in a certain domain of activity, like the publication record of a scientist or the winning record of an athlete or a team, captures the actions of an individual entity. In contrast, success, captured by fame, celebrity, popularity, impact or visibility, is a collective measure, representing a community's reaction to and acceptance of an individual entity's performance. The link between these two measures, while is often taken for granted, is actually far from being understood and often controversial.

 

EDITORIAL
Roberta Sinatra and Renaud Lambiotte

Advances in Complex Systems Vol. 21, No. 03n04, 1802001 (2018) https://doi.org/10.1142/S0219525918020010

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The future of hyperdiverse tropical ecosystems

The future of hyperdiverse tropical ecosystems | Papers | Scoop.it

The tropics contain the overwhelming majority of Earth’s biodiversity: their terrestrial, freshwater and marine ecosystems hold more than three-quarters of all species, including almost all shallow-water corals and over 90% of terrestrial birds. However, tropical ecosystems are also subject to pervasive and interacting stressors, such as deforestation, overfishing and climate change, and they are set within a socio-economic context that includes growing pressure from an increasingly globalized world, larger and more affluent tropical populations, and weak governance and response capacities. Concerted local, national and international actions are urgently required to prevent a collapse of tropical biodiversity.

 

The future of hyperdiverse tropical ecosystems
Jos Barlow, et al.
Nature volume 559, pages 517–526 (2018)


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Key Features of Turing Systems are Determined Purely by Network Topology

Turing’s theory of pattern formation is a universal model for self-organization, applicable to many systems in physics, chemistry, and biology. Essential properties of a Turing system, such as the conditions for the existence of patterns and the mechanisms of pattern selection, are well understood in small networks. However, a general set of rules explaining how network topology determines fundamental system properties and constraints has not been found. Here we provide a first general theory of Turing network topology, which proves why three key features of a Turing system are directly determined by the topology: the type of restrictions that apply to the diffusion rates, the robustness of the system, and the phase relations of the molecular species.

 

Key Features of Turing Systems are Determined Purely by Network Topology

Xavier Diego, Luciano Marcon, Patrick Müller, and James Sharpe
Phys. Rev. X 8, 021071

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General complexity: A philosophical and critical perspective

In this paper we argue that a rigorous understanding of the nature and implications of complexityreveals that the underlying assumptions that inform our understanding of complex phenomena are deeply related to general philosophical issues. We draw on a very specific philosophical interpretation of complexity, as informed by the work of Paul Cilliers and Edgar Morin. This interpretation of complexity, we argue, resonates with specific themes in post-structural philosophy in general, and deconstruction in particular. We argue that post-structural terms such as différance carry critical insights into furthering our understanding of complexity. The defining feature that distinguishes the account of complexity offered here to other contemporary theories of complexity is the notion of critique. The critical imperative that can be located in a philosophical interpretation of complexity exposes the limitations of totalising theories and subsequently calls for examining the normativity inherent in the knowledge claims that we make. The conjunction of complexity and post-structuralism inscribes a critical-emancipatory impetus into the complexity approach that is missing from othertheories of complexity. We therefore argue for the importance of critical complexity against reductionist or restricted understandings of complexity.

 

General complexity: A philosophical and critical perspective. Emergence: Complexity and Organization.
June 2018
DOI: 10.emerg/10.17357.c9734094d98458109d25b79d546318af.
Rika Preiser, Minka  Woermann, Oliver Human

 

 

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A dynamical systems approach to gross domestic product forecasting

A dynamical systems approach to gross domestic product forecasting | Papers | Scoop.it
Models developed for gross domestic product (GDP) growth forecasting tend to be extremely complex, relying on a large number of variables and parameters. Such complexity is not always to the benefit of the accuracy of the forecast. Economic complexity constitutes a framework that builds on methods developed for the study of complex systems to construct approaches that are less demanding than standard macroeconomic ones in terms of data requirements, but whose accuracy remains to be systematically benchmarked. Here we develop a forecasting scheme that is shown to outperform the accuracy of the five-year forecast issued by the International Monetary Fund (IMF) by more than 25% on the available data. The model is based on effectively representing economic growth as a two-dimensional dynamical system, defined by GDP per capita and ‘fitness’, a variable computed using only publicly available product-level export data. We show that forecasting errors produced by the method are generally predictable and are also uncorrelated to IMF errors, suggesting that our method is extracting information that is complementary to standard approaches. We believe that our findings are of a very general nature and we plan to extend our validations on larger datasets in future works.

 

A dynamical systems approach to gross domestic product forecasting
A. Tacchella, D. Mazzilli & L. Pietronero
Nature Physicsvolume 14, pages 861–865 (2018)

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Rule Primality, Minimal Generating Sets and Turing-Universality in the Causal Decomposition of Elementary Cellular Automata

New Universality results in Elementary Cellular Automata by emulation of Rule 110 just published by the Journal of Cellular Automata: https://goo.gl/vWQsCk . Also available at: https://arxiv.org/abs/1802.08769  includes a minimal set of only 38 ECAs generating all others under composition and 2 new Turing universal 4-colour cellular automata.

 

"We introduce several concepts such as prime and composite rule, tools and methods for causal composition and decomposition. We discover and prove new universality results in ECA, namely, that the Boolean composition of ECA rules 51 and 118, and 170, 15 and 118 can emulate ECA rule 110 and are thus Turing-universal coupled systems. We construct two 4-colour Turing-universal cellular automata that carries the Boolean composition of the 2 and 3 ECA rules emulating ECA rule 110 under multi-scale coarse-graining. We find that rules generating the ECA rulespace by Boolean composition are of low complexity and comprise prime rules implementing basic operations that when composed enable complex behaviour. We also found a candidate minimal set with only 38 ECA prime rules — and several other small sets — capable of generating all other (non-trivially symmetric) 88 ECA rules under Boolean composition."

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The power of many

Three billion years ago, more or less, life crossed a threshold and began moving toward a multicellular existence. Evidence from multiple directions is showing how this hard-to-fathom leap might have been less difficult than once believed. The evolutionary histories of some groups of organisms record numerous transitions from single-celled to multicellular forms, suggesting the hurdles could not have been so high. Genetic comparisons between simple multicellular organisms and their single-celled relatives have revealed that much of the molecular equipment needed for cells to band together and coordinate their activities may have been in place well before multicellularity evolved. And clever experiments have shown that in the test tube, single-celled life can evolve the beginnings of multicellularity in just a few hundred generations—an evolutionary instant. The end result: the incredible diversity of life seen today.

 

The power of many
Elizabeth Pennisi
Science  29 Jun 2018:
Vol. 360, Issue 6396, pp. 1388-1391
DOI: 10.1126/science.360.6396.1388

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Assessing diversity in multiplex networks

Diversity, understood as the variety of different elements or configurations that an extensive system has, is a crucial property that allows maintaining the system's functionality in a changing environment, where failures, random events or malicious attacks are often unavoidable. Despite the relevance of preserving diversity in the context of ecology, biology, transport, finances, etc., the elements or configurations that more contribute to the diversity are often unknown, and thus, they can not be protected against failures or environmental crises. This is due to the fact that there is no generic framework that allows identifying which elements or configurations have crucial roles in preserving the diversity of the system. Existing methods treat the level of heterogeneity of a system as a measure of its diversity, being unsuitable when systems are composed of a large number of elements with different attributes and types of interactions. Besides, with limited resources, one needs to find the best preservation policy, i.e., one needs to solve an optimization problem. Here we aim to bridge this gap by developing a metric between labeled graphs to compute the diversity of the system, which allows identifying the most relevant components, based on their contribution to a global diversity value. The proposed framework is suitable for large multiplex structures, which are constituted by a set of elements represented as nodes, which have different types of interactions, represented as layers. The proposed method allows us to find, in a genetic network (HIV-1), the elements with the highest diversity values, while in a European airline network, we systematically identify the companies that maximize (and those that less compromise) the variety of options for routes connecting different airports.


Assessing diversity in multiplex networks
L.C. Carpi, T.A. Schieber, P.M. Pardalos, G. Marfany, C. Masoller, A. Díaz-Guilera, M.G. Ravetti

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Vulnerability to pandemics in a rapidly urbanizing society

We examine salient trends of influenza pandemics in Australia, a rapidly urbanizing nation. To do so, we implement state-of-the-art influenza transmission and progression models within a large-scale stochastic computer simulation, generated using comprehensive Australian census datasets from 2006, 2011, and 2016. Our results offer the first simulation-based investigation of a population's sensitivity to pandemics across multiple historical time points, and highlight three significant trends in pandemic patterns over the years: increased peak prevalence, faster spreading rates, and decreasing spatiotemporal bimodality. We attribute these pandemic trends to increases in two key quantities indicative of urbanization: population fraction residing in major cities, and international air traffic. In addition, we identify features of the pandemic's geographic spread that can only be attributed to changes in the commuter mobility network. The generic nature of our model and the ubiquity of urbanization trends around the world make it likely for our results to be applicable in other rapidly urbanizing nations.

 


Vulnerability to pandemics in a rapidly urbanizing society
Cameron Zachreson, Kristopher M. Fair, Oliver M. Cliff, Nathan Harding, Mahendra Piraveenan, Mikhail Prokopenko

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Twenty years of network science

Twenty years of network science | Papers | Scoop.it
The idea that everyone in the world is connected to everyone else by just six degrees of separation was explained by the ‘small-world’ network model 20 years ago. What seemed to be a niche finding turned out to have huge consequences.
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Predicting perturbation patterns from the topology of biological networks

High-throughput technologies, offering unprecedented wealth of quantitative data underlying the makeup of living systems, are changing biology. Notably, the systematic mapping of the relationships between biochemical entities has fueled the rapid development of network biology, offering a suitable framework to describe disease phenotypes and predict potential drug targets. Yet, our ability to develop accurate dynamical models remains limited, due in part to the limited knowledge of the kinetic parameters underlying these interactions. Here, we explore the degree to which we can make reasonably accurate predictions in the absence of the kinetic parameters. We find that simple dynamically agnostic models are sufficient to recover the strength and sign of the biochemical perturbation patterns observed in 87 biological models for which the underlying kinetics is known. Surprisingly, a simple distance-based model achieves 65% accuracy. We show that this predictive power is robust to topological and kinetic parameters perturbations, and we identify key network properties that can increase up to 80% the recovery rate of the true perturbation patterns. We validate our approach using experimental data on the chemotactic pathway in bacteria, finding that a network model of perturbation spreading predicts with ~80% accuracy the directionality of gene expression and phenotype changes in knock-out and overproduction experiments. These findings show that the steady advances in mapping out the topology of biochemical interaction networks opens avenues for accurate perturbation spread modeling, with direct implications for medicine and drug development.

 

Predicting perturbation patterns from the topology of biological networks

Marc Santolini, Albert-Laszlo Barabasi
doi: https://doi.org/10.1101/349324

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Quantifying the ecological diversity and health of online news

Even in developed countries with an active free press, news coverage can be dominated by only a few players. This can lead to a reduction of topical and community diversity. Ownership structures might further limit coverage by implicitly or explicitly biasing editorial policies. In this paper, we apply ecological diversity measures to quantify the health of the Chilean online news ecology using extensive ownership and social media data. Results indicate that high levels concentration characterizes the Chilean media landscape in terms of ownership and topical coverage. Our methods reveal which groups of outlets and ownership exert the greatest influence on news coverage and can be generalized to any nation's news system.

 

Quantifying the ecological diversity and health of online news

Erick Elejalde, Leo Ferres, Eelco Herder, Johan Bollen

Journal of Computational Science

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Vicky Prefers Voltaire to Vogue: Obstacles to the Self-actualisation of Gifted Women within Social Systems

Giftedness is characterized by high intellectual capabilities and ambitions, unconventional thinking, and a drive to learn and be creative. We argue that gifted women face specific obstacles that, for many, have precluded their ability to develop their gifts, hindered their educational development and career, and made them feel frustrated and unfulfilled. We analyse testimonies of gifted women that we collected from across the globe to provide concrete evidence of these hurdles, thereby highlighting their struggles, while noting in particular their experiences of shame, guilt, fear and self-doubt. A full understanding of these issues requires a deconstruction of the symbolic paradigm that underpins the social system we live in. As gifted women are by nature drawn to creative, independent, intellectual pursuits, they deviate from the norms imposed by the social system. The resulting negative reactions frequently lead them to believe there is something intrinsically wrong with them. This produces the painful emotion of shame, which potently suppresses self- actualization.

 

Vicky Prefers Voltaire to Vogue:

Obstacles to the Self-actualisation of Gifted Women within
Social Systems
Kate KINGSBURY & Francis HEYLIGHEN

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Hot streaks in artistic, cultural, and scientific careers

Hot streaks in artistic, cultural, and scientific careers | Papers | Scoop.it

The hot streak—loosely defined as ‘winning begets more winnings’—highlights a specific period during which an individual’s performance is substantially better than his or her typical performance. Although hot streaks have been widely debated in sports, gambling and financial markets over the past several decades, little is known about whether they apply to individual careers. Here, building on rich literature on the lifecycle of creativity, we collected large-scale career histories of individual artists, film directors and scientists, tracing the artworks, films and scientific publications they produced. We find that, across all three domains, hit works within a career show a high degree of temporal regularity, with each career being characterized by bursts of high-impact works occurring in sequence. We demonstrate that these observations can be explained by a simple hot-streak model, allowing us to probe quantitatively the hot streak phenomenon governing individual careers. We find this phenomemon to be remarkably universal across diverse domains: hot streaks are ubiquitous yet usually unique across different careers. The hot streak emerges randomly within an individual’s sequence of works, is temporally localized, and is not associated with any detectable change in productivity. We show that, because works produced during hot streaks garner substantially more impact, the uncovered hot streaks fundamentally drive the collective impact of an individual, and ignoring this leads us to systematically overestimate or underestimate the future impact of a career. These results not only deepen our quantitative understanding of patterns that govern individual ingenuity and success, but also may have implications for identifying and nurturing individuals whose work will have lasting impact.

 

Hot streaks in artistic, cultural, and scientific careers
Lu Liu, Yang Wang, Roberta Sinatra, C. Lee Giles, Chaoming Song & Dashun Wang 
Nature volume 559, pages 396–399 (2018)

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Who would you share your funding with?

Who would you share your funding with? | Papers | Scoop.it
I want to see whether the wisdom of crowds does a better job than conventional grant review at supporting research, says Johan Bollen.
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Optimized flocking of autonomous drones in confined environments

Optimized flocking of autonomous drones in confined environments | Papers | Scoop.it

We address a fundamental issue of collective motion of aerial robots: how to ensure that large flocks of autonomous drones seamlessly navigate in confined spaces. The numerous existing flocking models are rarely tested on actual hardware because they typically neglect some crucial aspects of multirobot systems. Constrained motion and communication capabilities, delays, perturbations, or the presence of barriers should be modeled and treated explicitly because they have large effects on collective behavior during the cooperation of real agents. Handling these issues properly results in additional model complexity and a natural increase in the number of tunable parameters, which calls for appropriate optimization methods to be coupled tightly to model development. In this paper, we propose such a flocking model for real drones incorporating an evolutionary optimization framework with carefully chosen order parameters and fitness functions. We numerically demonstrated that the induced swarm behavior remained stable under realistic conditions for large flock sizes and notably for large velocities. We showed that coherent and realistic collective motion patterns persisted even around perturbing obstacles. Furthermore, we validated our model on real hardware, carrying out field experiments with a self-organized swarm of 30 drones. This is the largest of such aerial outdoor systems without central control reported to date exhibiting flocking with collective collision and object avoidance. The results confirmed the adequacy of our approach. Successfully controlling dozens of quadcopters will enable substantially more efficient task management in various contexts involving drones.

 

Optimized flocking of autonomous drones in confined environments
Gábor Vásárhelyi, Csaba Virágh, Gergő Somorjai, Tamás Nepusz, Agoston E. Eiben and Tamás Vicsek
Science Robotics  18 Jul 2018:
Vol. 3, Issue 20, eaat3536
DOI: 10.1126/scirobotics.aat3536

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Evidence for a conserved quantity in human mobility

Evidence for a conserved quantity in human mobility | Papers | Scoop.it

Recent seminal works on human mobility have shown that individuals constantly exploit a small set of repeatedly visited locations1,2,3. A concurrent study has emphasized the explorative nature of human behaviour, showing that the number of visited places grows steadily over time4,5,6,7. How to reconcile these seemingly contradicting facts remains an open question. Here, we analyse high-resolution multi-year traces of ~40,000 individuals from 4 datasets and show that this tension vanishes when the long-term evolution of mobility patterns is considered. We reveal that mobility patterns evolve significantly yet smoothly, and that the number of familiar locations an individual visits at any point is a conserved quantity with a typical size of ~25. We use this finding to improve state-of-the-art modelling of human mobility4,8. Furthermore, shifting the attention from aggregated quantities to individual behaviour, we show that the size of an individual’s set of preferred locations correlates with their number of social interactions. This result suggests a connection between the conserved quantity we identify, which as we show cannot be understood purely on the basis of time constraints, and the ‘Dunbar number’9,10 describing a cognitive upper limit to an individual’s number of social relations. We anticipate that our work will spark further research linking the study of human mobility and the cognitive and behavioural sciences.

 

Evidence for a conserved quantity in human mobility
Laura Alessandretti, Piotr Sapiezynski, Vedran Sekara, Sune Lehmann & Andrea Baronchelli 
Nature Human Behaviour volume 2, pages 485–491 (2018)

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Does putting your emotions into words make you feel better? Measuring the minute-scale dynamics of emotions from online data

Studies of affect labeling, i.e. putting your feelings into words, indicate that it can attenuate positive and negative emotions. Here we track the evolution of individual emotions for tens of thousands of Twitter users by analyzing the emotional content of their tweets before and after they explicitly report having a strong emotion. Our results reveal how emotions and their expression evolve at the temporal resolution of one minute. While the expression of positive emotions is preceded by a short but steep increase in positive valence and followed by short decay to normal levels, negative emotions build up more slowly, followed by a sharp reversal to previous levels, matching earlier findings of the attenuating effects of affect labeling. We estimate that positive and negative emotions last approximately 1.25 and 1.5 hours from onset to evanescence. A separate analysis for male and female subjects is suggestive of possible gender-specific differences in emotional dynamics.

 

Does putting your emotions into words make you feel better? Measuring the minute-scale dynamics of emotions from online data

Rui Fan, Ali Varamesh, Onur Varol, Alexander Barron, Ingrid van de Leemput, Marten Scheffer, Johan Bollen

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Tomorrow's Earth

Tomorrow's Earth | Papers | Scoop.it
As the human population has grown over recent decades, our profound impact on the entire planet has become starkly apparent. Increasing affluence has led to expectations of good-quality health care, full employment, and the ability to live in cities that are safe, affordable, and clean. Yet these advantages for some come at a cost to others and to the planet itself. Human activities have led to a warming climate, massive landscape conversion, pollution, depletion of natural resources (crucially, fresh water and soil), defaunation, and loss of biodiversity. Today, global human society stands at a decision point. Business-as-usual approaches are likely to lead to catastrophic changes to our planet and our health and well-being. What will it take for universal recognition of our perilous position, and how can we begin to make the often-difficult changes required to live in a more sustainable, cooperative, and compassionate way? In this special series, we call attention to these choices and explore some of the possible routes to a more sustainable future.
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Social Physics: Uncovering Human Behaviour from Communication

In the post year 2000 era the technologies that facilitate human communication have rapidly multiplied. While the adoption of these technologies has hugely impacted the behaviour and sociality of people, specifically in urban but also in rural environments, their "digital footprints" on different data bases have become an active area of research. The existence and accessibility of such large population-level datasets, has allowed scientists to study and model innate human tendencies and social patterns in an unprecedented way that complements traditional research approaches like questionnaire studies. In this review we focus on data analytics and modelling research - we call Social Physics - as it has been carried out using the mobile phone data sets to get insight into the various aspects of human sociality, burstiness in communication, mobility patterns, and daily rhythms.

 

Social Physics: Uncovering Human Behaviour from Communication
Kunal Bhattacharya, Kimmo Kaski

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Methods for Measuring Viability and Evaluating Viability Indicators

Life and other dissipative structures involve nonlinear dynamics that are not amenable to conventional analysis. Advances are being made in theory, modeling, and simulation techniques, but we do not have general principles for designing, controlling, stabilizing, or eliminating these systems. There is thus a need for tools that can transform high-level descriptions of these systems into useful guidance for their modification and design. In this article we introduce new methods for quantifying the viability of dissipative structures. We then present an information-theoretical approach for evaluating the quality of viability indicators, measurable quantities that covary with, and thus can be used to predict or influence, a system's viability.

 

Methods for Measuring Viability and Evaluating Viability Indicators

Matthew D. Egbert and Juan Pérez-Mercader

Artificial Life
Volume 24 | Issue 2 | Spring 2018
p.106-118

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Semantic information, agency, and nonequilibrium statistical physics

Information theory provides various measures of correlations holding between the states of two systems, which are sometimes called measures of "syntactic information". At the same time, the concept of "semantic information" refers to information which is in some sense meaningful rather than merely correlational. Semantic information plays an important role in many fields -- including biology, cognitive science, artificial intelligence -- and there has been a long-standing interest in a quantitative theory of semantic information. In this work, we introduce such a theory, which defines semantic information as the syntactic information that a physical system has about its environment that is causally necessary for the system to maintain its own existence. We operationalize self-maintenance in terms of the ability of the system to maintain a low entropy state, which we use to make connections to results in nonequilibrium statistical physics. Our approach leads naturally to formal definitions of notions like "value of information", "semantic content", and "agency". Our approach is grounded purely in the intrinsic dynamics of a system coupled to some environment, and is applicable to any physical system.


Semantic information, agency, and nonequilibrium statistical physics
Artemy Kolchinsky, David H. Wolpert

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The clock of chemical evolution

Chemical evolution is essential in understanding the origins of life. We present a theory for the evolution of molecule masses and show that small molecules grow by random diffusion and large molecules by a preferential attachment process leading eventually to life's molecules. It reproduces correctly the distribution of molecules found via mass spectroscopy for the Murchison meteorite and estimates the start of chemical evolution back to 12.8 billion years following the birth of stars and supernovae. From the Frontier mass between the random and preferential attachment dynamics the birth time of molecule families can be estimated. Amino acids emerge about 165 million years after the start of evolution. Using the scaling of reaction rates with the distance of the molecules in space we recover correctly the few days emergence time of amino acids in the Miller-Urey experiment. The distribution of interstellar and extragalactic molecules are both consistent with the evolutionary mass distribution, and their age is estimated to 108 and 65 million years after the start of evolution. From the model, we can determine the number of different molecule compositions at the time of the creation of Earth to be 1.6 million and the number of molecule compositions in interstellar space to a mere 719.


The clock of chemical evolution
Stuart A. Kauffman, David P. Jelenfi, Gabor Vattay

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Misinformation and biases infect social media, both intentionally and accidentally

Social media are among the primary sources of news in the U.S. and across the world. Yet users are exposed to content of questionable accuracy, including conspiracy theories, clickbait, hyperpartisan content, pseudo science and even fabricated “fake news” reports.

It’s not surprising that there’s so much disinformation published: Spam and online fraud are lucrative for criminals, and government and political propaganda yield both partisan and financial benefits. But the fact that low-credibility content spreads so quickly and easily suggests that people and the algorithms behind social media platforms are vulnerable to manipulation.

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Universal migration predicts human movements under climate change

Universal migration predicts human movements under climate change | Papers | Scoop.it
Climate change is expected to displace millions of people through impacts like sea level rise, crop failures, and more frequent extreme weather. Yet scientists still cannot predict where these expected climate-induced migrants are likely to go in the coming decades. A new study, published today in Environmental Research Letters, seeks to address this nee

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