Abstract
For the few scientists that earn a Nobel prize, the im-, D.J. Scalapino, G. Parisi, pact and relevance of their research work is unquestion- S.G. Louie, R. Jackiw, F. Wilczek able. Among the rest of us, how does one quantify the, C. Vafa, M.B. Maple, D.J. cumulative impact and relevance of an individual’s sci- Gross, M.S. Dresselhaus, S.W. Hawkentific research output? In a world of not unlimited reing. sources such quantification (even if potentially distaste- I argue that h is preferable to other single-number cri-