Zhuo Qun Song

Canadian mathematician best known for winning five IMO gold medals (2010-2015), a record at the time. Princeton Mathematics graduate (2019); worked as a Quantitative Researcher at Citadel (2019-2021) and held Jane Street trading internships (2017, 2018). Since 2022 a Mathematics PhD student at the University of Illinois Urbana-Champaign.

Notes9

• Quant employment verification: CONFIRMED. Zhuo Qun (Alex) Song held an actual quantitative-finance role: Quantitative Researcher at Citadel (Citadel Enterprise Americas), per Wikipedia ('previously a Quantitative Researcher at Citadel') and efinancialcareers (18 Aug 2023), which states he worked at Citadel as a quant researcher for two years and at Jane Street; the LinkedIn index additionally lists Citadel Quantitative Researcher (Greater Chicago, 2019-2021) and Jane Street Trading Internships (2017, 2018). Employer classification: Citadel (citadel.com) and Jane Street (janestreet.com) are hedge fund / proprietary trading firms that run quantitative and systematic trading; both are genuine quantitative-finance employers, not merely 'quant'-named. Identity is supported: the same person is the five-time IMO gold medalist (Princeton Math 2019, UIUC Math PhD). The Citadel role and Jane Street internships therefore establish employment; competitions, camps, scholarships and offers do not.
• The efinancialcareers article (18 Aug 2023) states Song 'worked at both Jane Street and Citadel' and describes the Citadel quant researcher role as lasting two years, which corroborates the LinkedIn-index dated entry (2019-2021) with an independent primary-source-style report rather than index-only data.
• Wikipedia lists his education as Princeton and states he was previously a Quantitative Researcher at Citadel, corroborating that the finance role is past, not current.
• The LinkedIn index labels Citadel as his current employer while its own dated role history ends that Citadel post in 2021 and his education shows an ongoing UIUC Mathematics PhD from 2022; the entries conflict, so Citadel is treated as a PAST role and current employment is not asserted from the index.
• UIUC Department of Mathematics directory lists Alex Song (zqsong2) with research area Number Theory, confirming current academic affiliation and public institutional email [contact omitted].
• LinkedIn index (index-only, not independent confirmation) lists prior roles: Citadel Quantitative Researcher (Greater Chicago Area, 2019-2021, 2 yrs); Jane Street Trading Intern (Greater New York City Area, 2018); Jane Street Trading Intern (2017); and an Emory University analytical number theory REU participant (2016).
• Laureates.ca biography: born in Tianjin, China in 1997; parents immigrated to Canada in 2002 and settled in Waterloo, Ontario; began math competitions in Grade 1, attended the 2010 CMS Winter Camp, and won 1st place in the Canadian Math Olympiad before his first IMO.
• IMU/IMO official contestant record lists Zhuo Qun (Alex) Song competing for Canada across 2010-2015 (contestant 19624); the Wikipedia results table shows golds in 2015, 2014 and 2013 with the earlier years below, and public summaries describe '5 golds' - the exact per-year medal set (2010 vs gold) should be read from the official IMO page.
• Co-author of 'Bounded Gaps Between Products of Distinct Primes' (arXiv:1607.03887), a number-theory research paper, showing sustained mathematical research output beyond competitions.
• Po-Shen Loh (public post) notes Song 'is an instructor at that program' for Jane Street's AMP program, a teaching affiliation distinct from his trading internships there.
• Wikidata lists employer 'Citadel Enterprise Americas' for Song, an additional database record (index-style, not independent primary confirmation) of the Citadel role.
• Laureates.ca states his parents moved the family from Canada to the US (framed around his mathematical development), indicating the family relocated rather than an individual decision; no source states a reason for later moves.