{{short description|American mathematician}} {{Use mdy dates|date=January 2017}} {{Infobox scientist |name = Moon Duchin |image = |caption = |birth_name = |birth_date = |birth_place = |death_date = |death_place = |citizenship = |fields = Mathematics |workplaces = Cornell University, Tufts University |alma_mater = Harvard University (BA Mathematics and Women's Studies 1998)<ref name="TischBio">{{cite web |title=Moon Duchin |url=https://tischcollege.tufts.edu/people/faculty/moon-duchin |website=Jonathan M. Tisch College of Civic Life |publisher=Tufts University |access-date=2021-09-28 |language=en |date=8 September 2017}}</ref><br>University of Chicago (MS Mathematics 1999, PhD Mathematics 2005)<ref name="TischBio"/> |thesis_title = Thin triangles and a multiplicative ergodic theorem for Teichmüller geometry |thesis_url = https://arxiv.org/abs/math/0508046 |thesis_year = 2005 |doctoral_advisor = Alex Eskin |academic_advisors = |doctoral_students = |notable_students = |known_for = Research in geometric group theory and the mathematics of gerrymandering |influences = |influenced = |awards = Fellow of the American Mathematical Society, Guggenheim Fellowship |signature = |footnotes = }} '''Moon Duchin''' is an American mathematician who works as a professor at The University of Chicago. Her mathematical research concerns geometric topology, geometric group theory, and Teichmüller theory.<ref name="FacProfile">{{cite web |title=Department of Mathematics: People: Moon Duchin |url=http://math.tufts.edu/people/facultyDuchin.htm |website=math.tufts.edu |publisher=Tufts University |accessdate=2019-03-08 |archive-date=February 24, 2019 |archive-url=https://web.archive.org/web/20190224000026/http://math.tufts.edu/people/facultyDuchin.htm |url-status=dead }}</ref> She has done significant research on the mathematics of redistricting and gerrymandering, and founded a research group, MGGG Redistricting Lab, to advance these mathematical studies and their nonpartisan application in the real world of US politics.<ref>{{Cite web|title=Our Mission|url=https://www.mggg.org/|access-date=2021-11-02|website=Metric Geometry and Gerrymandering Group|language=en}}</ref> She is also interested in the cultural studies, philosophy, and history of science.<ref name="FacProfile"/> Duchin was one of the core faculty members and served as director of the Science, Technology, and Society program at Tufts.<ref name="TischBio"/><ref name="FacProfile"/>
==Early life and education== Duchin was born to Faye Duchin, an economist, and Micha Brym.<ref name=":0">{{Cite news |last=Shelton |first=Stacy |date=1993-02-01 |title=Young scholar shines in national tourney |url=https://www.newspapers.com/article/stamford-advocate-young-scholar-shines-i/197401448/ |access-date=2026-05-12 |work=Stamford Advocate |pages=A3, [https://www.newspapers.com/article/stamford-advocate/197401501/ A8]}}</ref> Duchin was given her first name, Moon, by parents "on the science-y fringes of the hippie classification".<ref name="sciam"/> She was given her mother's last name, and her sister was given her father's.<ref name=":0" /> She grew up knowing from a young age that she wanted to become a mathematician.<ref name="sciam"/> As a student at Stamford High School in Connecticut, she completed the regular high school mathematics curriculum in her sophomore year, and continued to learn mathematics through independent study.<ref name="sciam"/> She was active in math and science camps and competitions, and did a summer research project in the geometry of numbers with Noam Elkies.<ref name="sciam">{{citation|title=Blazing a trail for women in math: Moon Duchin|magazine=Scientific American|first=Laura|last=Vanderkam|date=June 23, 2008|url=https://www.scientificamerican.com/article/blazing-a-trail-for-women/}}.</ref>
Duchin studied at Harvard University as an undergraduate, where she was also active in queer organizing,<ref>{{citation|title=Defamatory Poster Appalls Students|first=Kristen|last=Welker|date=December 3, 1994|url=http://www.thecrimson.com/article/1994/12/3/defamatory-poster-appalls-students-pseveral-kirkland/|newspaper=The Harvard Crimson}}</ref> and finished a double major in mathematics and women's studies in 1998.<ref name="sciam"/><ref name="CV">{{cite web |title=Moon Duchin [CV] |url=https://mduchin.math.tufts.edu/CV-2016.pdf |website=math.tufts.edu |publisher=Tufts University |accessdate=2019-03-08}}</ref> At the time, she was unsure how to combine the two majors into a single thesis, so she decided to write two separate ones.<ref name="Strogatz">{{cite web |last1=Strogatz |first1=Steven |title=Moon Duchin on Fair Voting and Random Walks |url=https://www.quantamagazine.org/moon-duchin-on-fair-voting-and-random-walks-20200407/ |website=Quanta Magazine |access-date=2021-09-28 |language=en |date=7 April 2020}}</ref>
As a graduate student in mathematics at the University of Chicago, she continued feminist activism by teaching gender studies and pushing the university to add gender-neutral bathrooms,<ref name="sciam"/><ref>{{citation|url=https://www.lib.uchicago.edu/e/webexhibits/outinthequads/5710.html |title=Closeted/OUT in the Quadrangles: A History of LGBTQ Life at the University of Chicago |publisher=University of Chicago Libraries |year=2015 |accessdate=December 15, 2016 |archive-url=https://web.archive.org/web/20150426111711/https://www.lib.uchicago.edu/e/webexhibits/outinthequads/5710.html |archive-date=April 26, 2015 |url-status=dead}}.</ref> and was mentioned mockingly by name on the Rush Limbaugh show.<ref name="sciam"/> She completed her doctorate in 2005, under the supervision of Alex Eskin.<ref>{{mathgenealogy|id=33220}}</ref> She was a postdoctoral researcher at the University of California at Davis, and the University of Michigan, before joining the Tufts faculty in 2011.<ref name="sciam"/><ref name="CV"/>
==Work== Duchin's mathematical research has focused on geometric topology, geometric group theory, and Teichmüller theory.<ref name="FacProfile" /> For example, one of her results is that, for a broad class of locally flat surfaces, the geometry of the surface is entirely determined by the shortest length in each homotopy class of simple closed curves.<ref>Technically, "shortest length" here means an infimum of lengths, as there is not generally a single shortest representative curve for the class. See Bowman, Joshua Paul (2011). Review of {{citation|last1=Duchin|first1=Moon|title=Length spectra and degeneration of flat metrics|journal=Inventiones Mathematicae|volume=182|issue=2|pages=231–277|year=2010|arxiv=0907.2082|bibcode=2010InMat.182..231D|doi=10.1007/s00222-010-0262-y|mr=2729268|last2=Leininger|first2=Christopher J.|last3=Rafi|first3=Kasra|s2cid=10528656}}.</ref> In 2022 Duchin appeared in the Netflix documentary ''A Trip to Infinity'',<ref>{{Citation |last1=Halperin |first1=Jonathan |title=A Trip to Infinity |date=2022-09-26 |url=https://www.imdb.com/title/tt21929356/ |type=Documentary |publisher=Makemake, Room 608 |access-date=2022-10-22 |last2=Takahashi |first2=Drew}}</ref> discussing the mathematical implications of infinity.
Duchin's expertise in geometry has led her to conduct research on the mathematics of gerrymandering. A key aspect of this research is the geometric notion of the compactness of a given political district, a numerical measure that attempts to quantify how extensively gerrymandered it is.<ref name="scifri-geo">{{Cite web|url=https://www.sciencefriday.com/segments/can-geometry-root-out-gerrymandering/|title=Can Geometry Root Out Gerrymandering?|website=Science Friday|language=en-US|access-date=2019-01-26}}</ref> “What courts have been looking for is one definition of compactness that they can understand, that we can compute, and that they can use as a kind of go-to standard”, she said in an interview with ''The Chronicle of Higher Education''.<ref name="COHE"/>
To help tackle the challenge of finding an agreed-upon standard, Duchin has developed a long-term, wide-ranging project on the mathematics of gerrymandering.<ref name="COHE">{{Cite news|url=https://www.chronicle.com/article/Meet-the-Math-Professor/239260|title=Meet the Math Professor Who's Fighting Gerrymandering With Geometry|date=2017-02-22|work=The Chronicle of Higher Education|access-date=2018-09-05}}</ref> As a part of this project, she founded a summer program to train mathematicians to become expert witnesses in related legal cases.<ref name="MGGG-sites">{{Cite web |url=https://sites.tufts.edu/gerrymandr/project/ |title=Regional Sites – Metric Geometry and Gerrymandering Group |website=sites.tufts.edu |language=en-US |access-date=2018-09-05}}</ref><ref name="newyorker">{{Cite magazine|url=https://www.newyorker.com/tech/elements/a-summer-school-for-mathematicians-fed-up-with-gerrymandering|title=A Summer School for Mathematicians Fed Up with Gerrymandering|magazine=The New Yorker|access-date=2018-09-05|language=en-US}}</ref> In 2016, she founded the Metric Geometry and Gerrymandering Group (MGGG) which is a nonpartisan research group that coordinates and publicizes research on geometry, computing, and their application to the redistricting process in the US.<ref name="MGGG-Team">{{cite web |last1=Metric Geometry and Gerrymandering Group |title=Our Team |url=https://www.mggg.org/team.html |website=Metric Geometry and Gerrymandering Group |accessdate=2021-09-28}}</ref><ref name="Strogatz"/>
In 2018-2019 she took a leave of absence from Tufts, and was a Fellow at the Radcliffe Institute for Advanced Study at Harvard University. Her research focus was "Political Geometry: The Mathematics of Redistricting".<ref name="RIAS">{{cite web |title=Moon Duchin |url=https://www.radcliffe.harvard.edu/people/moon-duchin |website=Radcliffe Institute for Advanced Study at Harvard University |publisher=Harvard University |accessdate=2018-11-10 |language=en |date=5 April 2018}}</ref> In 2018, Governor of Pennsylvania Tom Wolf enlisted Duchin to help him evaluate newly drawn redistricting maps for fairness.<ref>{{Cite web|title=Governor Wolf to Enlist Mathematician to Evaluate Redistricting Maps|url=https://www.governor.pa.gov/newsroom/governor-wolf-enlist-non-partisan-mathematician-evaluate-fairness-redistricting-maps/|date=2018-01-26|website=Governor Tom Wolf|language=en-US|access-date=2020-05-14}}</ref> This happened as a consequence of the Supreme Court of Pennsylvania decision which declared the state's 2011 US congressional districting map to be unconstitutional.<ref>{{Cite web|title=Pennsylvania Supreme Court Holds Congressional Map Violates PA Constitution {{!}} The Public Interest Law Center|url=https://www.pubintlaw.org/cases-and-projects/pennsylvania-supreme-court-holds-congressional-map-violates-pa-constitution/|website=www.pubintlaw.org|language=en|access-date=2020-05-14}}</ref> Duchin prepared a report published on February 15, 2018.<ref>{{Cite web|title=Outlier analysis for Pennsylvania congressional redistricting|url=https://www.governor.pa.gov/wp-content/uploads/2018/02/md-report.pdf|last=Duchin|first=Moon|date=|website=Governor of Pennsylvania|url-status=live|archive-url=https://web.archive.org/web/20200324203546/https://www.governor.pa.gov/wp-content/uploads/2018/02/md-report.pdf|archive-date=March 24, 2020|access-date=May 14, 2020}}</ref><ref>{{Cite news|last=Ingraham|first=Christopher|date=February 13, 2018|title=Pennsylvania governor rejects Republicans' new congressional map|newspaper=The Washington Post|url=https://www.washingtonpost.com/news/wonk/wp/2018/02/13/pennsylvania-governor-rejects-republicans-new-congressional-map/|access-date=May 15, 2020}}</ref>
In 2022, a panel of judges threw out Alabama's soon-to-be-used congressional maps, citing the fact that the percentage of black people in the state had risen to about a quarter of the population. To draw some new, fairer maps, they turned to Duchin, who came up with 4 nearly-similar maps that would put the Black and Democratic-leaning cities of Mobile and Montgomery together, therefore complementing the one Black and blue-leaning district in the state with a second one.<ref>{{Cite web|last=Rakich|first=Ryan Best, Aaron Bycoffe and Nathaniel|date=2021-08-09|title=What Redistricting Looks Like In Every State - Alabama|url=https://projects.fivethirtyeight.com/redistricting-2022-maps/|archive-url=https://web.archive.org/web/20210809100425/https://projects.fivethirtyeight.com/redistricting-2022-maps/|url-status=dead|archive-date=August 9, 2021|access-date=2022-01-27|website=FiveThirtyEight|language=en}}</ref>
Duchin was hired by Cornell University in 2024 as part of the Brooks School of Public Policy and College of Arts and Sciences mathematics department.<ref>{{Cite web |title=Mathematician and redistricting expert joins Brooks School as radical collaboration hire |url=https://news.cornell.edu/stories/2024/09/mathematician-and-redistricting-expert-joins-brooks-school-radical-collaboration |access-date=2026-05-12 |website=Cornell Chronicle |language=en}}</ref> As of 2026, she is a professor at the University of Chicago.<ref>{{Cite web |title=Moon Duchin |url=https://computerscience.uchicago.edu/people/moon-duchin/ |access-date=2026-05-12 |website=Department of Computer Science |language=en-US}}</ref>
==Awards and honors== In 2016 Duchin was named as a Fellow of the American Mathematical Society "for contributions to geometric group theory and Teichmüller theory, and for service to the mathematical community".<ref>[https://www.ams.org/profession/ams-fellows/new-fellows 2017 Class of the Fellows of the AMS], accessed December 11, 2016.</ref> She was also a Mathematical Association of America Distinguished Lecturer for that year, speaking on the mathematics of voting systems.<ref>[http://www.maa.org/meetings/calendar-events/math-and-the-vote Math and the Vote: A Geometer Examines Elections], Mathematical Association of America, accessed December 11, 2016.</ref> In 2018 she was awarded a Guggenheim fellowship.<ref>{{Cite web|url=https://www.gf.org/fellows/all-fellows/moon-duchin/|title=John Simon Guggenheim Foundation {{!}} Moon Duchin|website=Guggenheim Foundation|access-date=September 5, 2018}}</ref>
==References== {{Reflist|30em}}
==External links== * [http://mduchin.math.tufts.edu/ Home page (Tufts University)] * [https://mggg.org/people/mduchin/docs/DuchinCV-2020.pdf Curriculum vitae, including list of publications] * [https://arxiv.org/abs/math/0508046 PhD dissertation]
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{{DEFAULTSORT:Duchin, Moon}} Category:Year of birth missing (living people) Category:Living people Category:21st-century American mathematicians Category:Harvard College alumni Category:University of Chicago alumni Category:Tufts University faculty Category:Fellows of the American Mathematical Society Category:21st-century American women mathematicians Category:American LGBTQ scientists Category:Stamford High School (Stamford, Connecticut) alumni Category:LGBTQ mathematicians Category:American LGBTQ academics Category:21st-century American LGBTQ people