On time-varying collaboration networks

The patterns of scientific collaboration have been frequently investigated in terms of complex networks without reference to time evolution. In the present work, we derive collaborative networks (from the arXiv repository) parameterized along time. By defining the concept of affine group, we identify several interesting trends in scientific collaboration, including the fact that the average size of the affine groups grows exponentially, while the number of authors increases as a power law. We were therefore able to identify, through extrapolation, the possible date when a single affine group is expected to emerge. Characteristic collaboration patterns were identified for each researcher, and their analysis revealed that larger affine groups tend to be less stable.

► We defined the concept of affine group of each author which corresponds to set of scientists if potential similar interests.
► Collaboration patterns were identified for each researcher, and their analysis revealed that larger collaboration groups tend to be less stable.
► We have found that the average size of the affine groups grows exponentially.
► There is a trend of the emergence of a single, giant affine group.
► Collaborations occur preferentially within affine groups.