From the wiki article :
Perelman resigned from his research post in Steklov Institute of Mathematics and in 2006 stated that he had quit professional mathematics, owing to feeling disappointed over the ethical standards in the field. >
Anybody have any idea what the ethical standards might be that he's referring to? Not sure if there's a scandal or something or just an overall sense of displeasure with the field.

For any not in the loop: https://en.wikipedia.org/wiki/Grigori_Perelman
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