Abstract
Language is a tool for cultural communication, and diffusion is influenced by many factors. However, many studies have highlighted the importance of language status, while the critical factor of minority identity has been neglected. Minority identity is a sociological factor reflecting individual preferences for minority languages. Here, we introduce a framework for characterizing the language diffusion within minority groups, leading to the emergence of new ethnolinguistic phenomena: language segregation and coexistence. This finding challenges the previous assumption that language status alone determines language dynamics. Furthermore, we add a self-minority identity transmission mechanism to understand how language diffusion occurs. Monte Carlo simulations and theoretical analyses reveal that self-minority identity transmission significantly fosters minority language diffusion in both heterogeneous and homogeneous networks, especially in heterogeneous networks, and that increasing the average degree of the network promotes minority language diffusion. Finally, we apply a real-world social network in the Wa minority region of Yunnan, China, to validate that minority language diffusion exhibits a phase transition and that the critical threshold depends on the network structure and the diffusion of self-minority identity. Moreover, we deepen the theoretical understanding of sociolinguistics and provide a theoretical basis and policy recommendations for protecting and promoting minority languages.