Why wasn't Lu Jeu Sham awarded the 1998 Nobel Prize with Walter Kohn? [closed]

Reviewing part of the history behind computational chemistry for my thesis I could not understand why only Walter Kohn was awarded the 1998 Nobel Prize in Chemistry (with John Pople getting the other half) if Lu Jeu Sham was equally important for laying the foundations of Density Functional Theory.

This post from Chemistry World suggests that Sham was excluded because he is not a "middle aged white man". I don't want to be provocative but was it even given a reason why only Kohn's name was immortalized while the 1965 paper is clearly authored by both men?

• Who would give such a reason officially? Aug 18 '21 at 19:50
• I know nothing about the development of DFT, but it is conceivable that the committee considered more than just the co-authorship of the original paper. Perhaps later papers were seen as driving the whole thing forward at least as much or more than the original one. Aug 18 '21 at 20:11
• The question may be better suited for SE site History of science and mathematics ( hsm.stackexchange.com ) Aug 19 '21 at 5:10
• Thank you. I believe that the two answers provided have a good reasoning and I am satisfied. Thank you so much. Aug 20 '21 at 12:02

Unfortunately, there is very rarely going to be an official statement as to why someone did not receive the Nobel Prize. A number of factors probably played into the decision. One of the big ones is that by rule, a single Nobel prize can be awarded to at most 3 individuals and at most 2 different works. This means that if third person were added to this prize, they would either be getting equal credit with Kohn for creating DFT or with Pople for development of computational methods.

You could make an argument for Sham or Hohenberg to be included on the DFT side, but with Kohn being an author on both the 1964 Hohenberg paper that introduced DFT and an author on the 1965 paper that made it practical through the KS formulation, its not unreasonable to claim that Kohn deserved more of the credit than either Sham or Hohenberg. Its also worth noting that Sham was Kohn's postdoc and Hohenberg had only just begun working at Bell Labs at the time of these publications; there could be a tendency to ascribe the work to the senior-most researcher.

There are a number of other factors you can consider (e.g. why assume Kohn's credit should be split rather than Pople's), but there will likely never be a definitive answer. The selection process is subjective and opaque. As the linked article suggests, it can be controversial and there are probably dozens of figures throughout history who you could argue deserved a Nobel Prize. But the prize is only awarded once a year to at most 2 works/3 people, so inevitably some works/researchers will be missed.

Some elements of the nomination are known (e.g., laureates of previous years may suggest as regularly do chemistry professors in Norwegian universities), but not all - especially not the discussions of the committees to elect up to three laureates per year and division. Thus, complementary to @Tyberius' answer, first paragraph, I would add paragraph 10 of the statutes of the Nobel Foundation as an obstacle here. At least at present time.

To quote:

§ 10.

No appeals may be made against the decision of a prize-awarding body with regard to the award of a prize.

Proposals received for the award of a prize, and investigations and opinions concerning the award of a prize, may not be divulged. Should divergent opinions have been expressed in connection with the decision of a prize-awarding body concerning the award of a prize, this may not be included in the record or otherwise divulged.

A prize-awarding body may, however, after due consideration in each individual case, permit access to material which formed the basis for the evaluation and decision concerning a prize, for purposes of research in intellectual history. Such permission may not, however, be granted until at least 50 years have elapsed after the date on which the decision in question was made.

(Any emphasize by italics was added by mine.)

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