Alex Fink
I am a Professor of Pure Mathematics in
the School of
Mathematical Sciences at
Queen Mary
University of London.
Office: 312, Maths Building, Mile End campus (number 4 on
this
map)
Telephone: 020 7882 5520
Email: a.fink@qmul.ac.uk
he / him
Support hours: see
my entry on the School's pages. Or email for an appointment.
Here is my CV.
Skip to:
Teaching
Administration
Activities
Group
Research
Publications
Teaching and tutoring
I have no teaching scheduled for the 2023/24 academic year.
Last year I taught
MTH4104, Introduction to Algebra.
In previous years I have taught an advanced graduate module on
Enumerative Combinatorics
at the London Taught Course Centre.
Administration
I am the head of the
Centre for Combinatorics, Algebra and Number Theory (CeCANT).
Activities
The weekly reading group of the
Tropical and Geometric Combinatorics research group at QMUL is currently running.
Some past activities organised:
I have profiles at
500 Queer Scientists and
LGBTQ+ STEM.
Group
I have three current PhD students:
and one current postdoc:
My former students are
Zeinab Toghani was a recent postdoc of mine.
Research
My research interests are principally in
algebraic combinatorics, especially where commutative algebra
or algebraic geometry apply, including
matroid theory and tropical geometry.
I hold EPSRC grant EP/X001229/1 Extensions of matroid Hodge theory. I have previously held EPSRC grant EP/M01245X/1
Algebra and geometry of matroids
and Horizon 2020 Marie SkłodowskaCurie grant No 792432
Tropical differential geometry.
Publications
 Journal articles, conference papers, preprints

 Alex Fink and Jorge Alberto Olarte, Extensions of transversal valuated matroids,
arXiv:2308.05556
(pdf).
 Christopher Eur, Alex Fink, Matt Larson and Hunter Spink, Signed permutohedra, deltamatroids, and beyond,
Proceedings of the London Mathematical Society 128 no. 3 (2024), e12592.
arXiv:2209.06752
(pdf).
 Javier Elizondo, Alex Fink and Cristhian Garay López, Matroids and the space of torusinvariant subvarieties of the Grassmannian with given homology class,
arXiv:2112.15334
(pdf).
 Laura Escobar, Alex Fink, Jenna Rajchgot and Alexander Woo, Gröbner bases, symmetric matrices, and type C Kazhdan–Lusztig varieties,
Journal of the London Mathematical Society 109 no. 2 (2024), e12856. doi:10.1112/jlms.12856.
arXiv:2104.09589
(pdf).
 Alex Fink and Zeinab Toghani, Initial forms and a notion of basis for tropical differential equations, Pacific Journal of Mathematics 318 no. 2 (2022), 453–468. doi:10.2140/pjm.2022.318.453.
arXiv:2004.08258
(pdf).
 Andrew Berget and Alex Fink, Equivariant Ktheory classes of matrix orbit closures, International Mathematics Research Notices 2022 no. 18 (2022), 14105–14133.
arXiv:1904.10047
(pdf).
 Alex Fink, Karola Mészáros and Avery St. Dizier, Zeroone Schubert polynomials,
Mathematische Zeitschrift 297 no. 3 (2020), 1023–1042.
doi:10.1007/s00209020025442.
arXiv:1903.10332
(pdf).
 Alex Fink and Jorge Alberto Olarte, Presentations of transversal valuated matroids, Journal of the London Mathematical Society 105 no. 1 (2022), 24–62,
published online.
arXiv:1903.08288
(pdf).
 Amanda Cameron and Alex Fink, The Tutte polynomial via lattice point counting, Journal of Combinatorial Theory, Series A 188 (2022), 105584.
arXiv:1802.09859
(pdf).
See also the FPSAC 2016 extended abstract.
 Clément Dupont, Alex Fink and Luca Moci,
Universal Tutte characters via combinatorial coalgebras,
Algebraic Combinatorics 1 no. 5 (2018), 603–651.
arXiv:1711.09028
(pdf).
Luca's notes
from his minicourse at Dobbiaco 2018.
 Alex Fink and Luca Moci,
Polytopes and parameter spaces for matroids over valuation rings,
Advances in Mathematics 343 (2019), 449–494.
doi:10.1016/j.aim.2018.11.009.
arXiv:1707.01026
(pdf).
Slides.
 Alex Fink, Karola Mészáros and Avery St. Dizier,
Schubert polynomials as integer point transforms of generalized permutahedra,
Advances in Mathematics 332 (2018), 465–475.
arXiv:1706.04935
(pdf).
 Alex Fink, David E Speyer and Alexander Woo,
A Gröbner basis for the graph of the reciprocal plane,
Journal of Commutative Algebra 12 no. 1 (2020), 77–86.
arXiv:1703.05967
(pdf).
 Alex Fink, Jenna Rajchgot and Seth Sullivant,
Matrix Schubert varieties and Gaussian conditional independence models,
arXiv:1510.04124
(pdf).
Journal of Algebraic Combinatorics 44 no. 4 (2016), 1009–1046.
 Andrew Berget and Alex Fink, Equivariant Chow classes
of matrix orbit closures,
Transformation Groups 22 no. 3 (2016),
published online.
doi:10.1007/s0003101694065.
arXiv:1507.05054
(pdf).
 Andrew Berget and Alex Fink, Matrix orbit closures,
Beiträge zur Algebra und Geometrie 59 no. 3 (2018), 1–34,
published online.
doi:10.1007/s133660180402x.
arXiv:1306.1810
(pdf).
 Alex Fink and Felipe Rincón, Stiefel tropical
linear spaces, Journal of Combinatorial Theory, Series A 135 (2015),
291–331.
arXiv:1305.6329
(pdf).
 Alex Fink and Luca Moci, Matroids over a ring,
Journal of the European Mathematical Society 18 issue 4 (2016), 681–731.
arXiv:1209.6571
(pdf).
Slides: motivation,
some details.
 Alex Fink,
BoijSöderberg
expansions of matroid StanleyReisner rings,
unpublished note.
 Alex Fink, Aviezri Fraenkel, Carlos Santos,
Lim is not slim,
International Journal of Game Theory 43 issue 2 (2014), 269–281.
doi:10.1007/s001820130380z.
Online at IJGT.
 Alex Fink, Lattice games without rational strategies,
Journal of Combinatorial Theory, Series A 119 (2012), 450–459.
doi:10.1016/j.jcta.2011.10.005.
arXiv:1106.1883
(pdf).
Slides.
 Alex Fink and David E Speyer, Kclasses of matroids
and equivariant localization, Duke Math. J. 161 no. 14 (2012),
2699–2723.
arXiv:1004.2403
(pdf).
Slides.
 Alex Fink, Tropical cycles and Chow polytopes,
Beiträge zur Algebra und Geometrie
54 no. 1 (2013), 13–40.
Online at Beiträge.
arXiv:1001.4784
(pdf).
Slides.
Video of the talk, MSRI, 16 October 2009.
 Harm Derksen and Alex Fink, Valuative invariants
for polymatroids, Advances in Mathematics
225 no. 4 (2010), 1840–1892.
doi:10.1016/j.aim.2010.04.016.
arXiv:0908.2988
(pdf).
Slides.
 Alex Fink, The binomial ideal of the intersection axiom
for conditional probabilities,
J. of Algebraic Combinatorics 33 issue 3 (2011), 455–463.
doi:10.1007/s1080101002535.
arXiv:0902.1495
(pdf).
Slides.
 Alex Fink, Richard Nowakowski, Aaron Siegel, David Wolfe,
Toppling conjectures, Games of No Chance 4,
MSRI Publications volume 63, 65–76.
 Alex Fink and Benjamin Iriarte Giraldo,
Bijections between noncrossing and nonnesting partitions
for classical reflection groups, Portugaliae Mathematicae
67 fasc. 3 (2010), 369–401.
arXiv:0810.2613
(pdf).
 Alex Fink and Richard K Guy,
The outercoarseness of the ncube,
Contributions to Discrete Math. 12 no. 2 (2017), #582.
 Alex Fink, Richard Guy and Mark Krusemeyer,
Partitions with parts appearing at most thrice,
Contributions to Discrete Math. 3 (2008), #79.
 Federico Ardila, Alex Fink and Felipe Rincón,
Valuations for matroid polytope subdivisions,
Canadian Journal of Mathematics,
published electronically on July 29, 2010.
doi:10.4153/CJM20100649.
arXiv:0710.4424
(pdf).
 Alex Fink, Jörg Denzinger, and John Aycock,
Extracting NPC behavior from Computer Games using Computer Vision
and Machine Learning Techniques, IEEE Symposium on
Computational Intelligence and Games, 2007, 24–31.
 Alex Fink and Richard Guy,
The numberpad game,
Coll. Math. J. 38 (2007), 260–264.
 Alex Fink,
A generalization of an IMO problem,
Integers, Electronic Journal of Combinatorial Number Theory
6 (2006), #A17.
 Alex Fink and Bill Sands,
Rationals whose sum equals the
reciprocal of their product, Crux Math. 30
(2004), 292–295.
 Doctoral thesis
 My thesis was titled
Matroid polytope subdivisions and valuations. Aside from an introduction all its content appears in the
papers above.
 Expository writing, manuscripts


Matroid subdivisions, and
a computational appendix.
Written for Jack Edmonds' 2015 summer courses on
Polyhedral Combinatorics and Exponential Polytime,
of which I gave a segment.
 Alex Fink and Richard Guy,
Rick's Tricky Six Puzzle:
S_{5} sits specially in S_{6},
Math. Magazine 82 no. 2 (April, 2009). See also Doug Ensley's
interactive supplement with implementations of the puzzle.
 If two were three,
what would Hex be?, 2008,
for Gathering for Gardner 8.
See also my other page
on this game, with an implementation.
 Patulous pegboard polygons,
with Derek Kisman and Richard Guy, 2006, for Gathering for Gardner 7,
in
Mathematical wizardry for a Gardner, AK Peters, 2009.
 Diversions
