Two Hierarchies in Science: The Free Flow of Ideas and the Academy

Two Hierarchies in Science: The Free Flow of Ideas and the Academy

Adrian Bejan 

J. A. Jones Distinguished Professor of Mechanical Engineering, Duke University, Durham, North Carolina, USA

31 December 2009
| Citation



Here I show that the pattern of generation of science is in disaccord with the pattern of admission to the academy. The contrast between the two patterns is illustrated with two rankings: the most highly cited authors in all US engineering and the members of the US National Academy of Engineering. Only 2.7% of the academy members are highly cited. This discrepancy raises the question of how the academicians have succeeded in this mode of self-organization. The answer is evident when we examine two drawings: (1) the numbers of highly cited authors versus the ranks of their institutions, and (2) the numbers of academy members versus the ranks of their institutions. Drawing (1) is a natural (Zipf) distribution, which is virtually the same as the hierarchy and scaling of all freely morphing flow structures in nature (e.g. city sizes on the landscape, tree sizes in the forest, and river sizes in the basins). Drawing (2) fails the natural (Zipf) test, and reveals that the flow to the academy is not free, that is, not for everybody.


constructal law, highly cited, national academy, mafias, dark networks, university rankings, Zipf distribution


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