Cover letter
Fanyuan Meng {letter} \openingDear Editor,
We would like to submit the enclosed manuscript, entitled ”Disagreement and fragmentation in growing groups”, for your consideration. Below, we briefly outline the main findings reported in this manuscript and the reasons why it deserves to be considered for publication as a research article to Chaos, Solitons & Fractals.
Social groups emerge spontaneously and continuously and form the building blocks of society. The mechanism behind group formation has thus attracted considerable interest in many disciplines, such as physics, economics, sociology, and psychology. The growth of a social group influences not only the topology of interactions among members (i.e., the structure of the social network) but also the multiplicity of opinions and their dynamics within the group. However, how the group growth shapes the agreement and disagreement among members and their opinions is still an understudied topic. This would be important to understand how disagreement emerges, how groups fragment, and how to prevent it.
To this end, we propose a group formation model in which individuals have binary views on various topics. The number of topics represents the dimensionality of the opinions. In our model, at each time step, new individuals enter the group with a probability proportional to the closeness of opinions with a randomly chosen group member. In addition, this ”admission rule” is subject to noise to model the unpredictability of human relationships.
We construct a compact mathematical formalism that captures all the main features of group formation in our model. Our main result is twofold. First, we find that disagreement among members inevitably emerges in groups that form spontaneously. Second, whatever the dimensionality of opinions, large groups cannot be stable and tend to fragment into small subgroups composed of like-minded members. Our findings advance the understanding of opinion formation in growing groups. They also suggest a complementary explanation to existing ones of the emergence of modularity in the social structure.
Overall, we believe that our paper is of interest to a wide audience and can enrich the publication profile of Chaos, Solitons & Fractals. We confirm that this manuscript has not been published elsewhere and is not under consideration by another journal. All authors have approved the manuscript and agree with its submission to Chaos, Solitons & Fractals.
Yours sincerely,