# blog

Welcome to my blog. You can browse it by year below, or by

## 2020

- Apr 02, 2020 Some updates
- Mar 17, 2020 Fortnightly links (102)
- Mar 01, 2020 Fortnightly links (101)
- Feb 05, 2020 Fortnightly links (100)
- Feb 03, 2020 Seminar announcement: exceptional collections on partial flag varieties
- Jan 19, 2020 Fortnightly links (99)
- Jan 05, 2020 Fortnightly links (98)

## 2019

- Dec 26, 2019 Fortnightly links (97)
- Dec 21, 2019 Gerby supports TikZ now
- Dec 12, 2019 le superficie algebriche: an update
- Dec 08, 2019 Fortnightly links (96)
- Nov 25, 2019 Fortnightly links (95)
- Nov 10, 2019 Fortnightly links (94)
- Nov 06, 2019 New tool: twisted Hodge diamonds for complete intersections
- Oct 29, 2019 A caveat on the notion of strongly simple
- Oct 28, 2019 Fortnightly links (93)
- Oct 14, 2019 Fortnightly links (92)
- Oct 07, 2019 Belgian–Dutch algebraic geometry day in Antwerp
- Sep 30, 2019 Fortnightly links (91)
- Sep 15, 2019 Fortnightly links (90)
- Sep 10, 2019 Fortnightly links (89)
- Aug 09, 2019 Registration for the Stacks Project Workshop 2020
- Aug 05, 2019 Fortnightly links (88)
- Jul 29, 2019 Fortnightly links (87)
- Jul 16, 2019 A minimal working example to use Gerby
- Jul 15, 2019 Fanography: del Pezzo surfaces
- Jul 08, 2019 Hodge numbers for Quot schemes on curves
- Jul 07, 2019 Fortnightly links (86)
- Jun 24, 2019 Fortnightly links (85)
- Jun 21, 2019 Stacks Project Workshop 2020: website
- Jun 11, 2019 Fortnightly links (84)
- May 24, 2019 Stacks Project Workshop 2
- May 13, 2019 Fortnightly links (83)
- May 09, 2019 Hodge numbers for O'Grady 10
- May 01, 2019 Fortnightly links (82)
- Apr 14, 2019 Fortnightly links (81)
- Mar 25, 2019 Fortnightly links (80)
- Mar 14, 2019 Moving to the University of Bonn
- Feb 03, 2019 Fortnightly links (79)
- Jan 27, 2019 New tool: Hodge diamond cutter
- Jan 16, 2019 Hodge numbers for Hilbert squares and Hilbert cubes
- Jan 13, 2019 Fortnightly links (78)
- Jan 04, 2019 Hodge numbers for partial flag varieties
- Jan 03, 2019 Fanography: updates
- Jan 01, 2019 Fortnightly links (77)

## 2018

- Dec 26, 2018 Roots of Hilbert polynomials for Fano toric varieties
- Dec 10, 2018 Fortnightly links (76)
- Dec 05, 2018 Recent CTAN additions: dynkin-diagrams, rank-2-roots
- Nov 25, 2018 Fortnightly links (75)
- Nov 22, 2018 Hodge diamonds and polyvector parallelograms
- Nov 14, 2018 Fortnightly links (74)
- Nov 01, 2018 Hodge numbers for generalised Kummer varieties
- Oct 31, 2018 Fortnightly links (73)
- Oct 18, 2018 Fortnightly links (72)
- Oct 17, 2018 Introducing Kerodon
- Oct 15, 2018 Fanography: a tool to visually study the geography of Fano 3-folds
- Oct 05, 2018 Fortnightly links (71)
- Sep 17, 2018 Fortnightly links (70)
- Sep 04, 2018 Fortnightly links (69)
- Aug 23, 2018 Index of partial flag varieties
- Aug 22, 2018 Rank of the Grothendieck group of partial flag varieties
- Aug 14, 2018 Hilbert squares of higher-dimensional hyperkähler varieties are not hyperkähler
- Aug 13, 2018 Fortnightly links (68)
- Aug 02, 2018 Fortnightly links (67)
- Jul 15, 2018 Fortnightly links (66)
- Jul 10, 2018 Peter Scholze is a new director of the Max Planck Institute for Mathematics
- Jul 03, 2018 Fortnightly links (65)
- Jun 18, 2018 Fortnightly links (64)
- Jun 15, 2018 Brill–Noether pictures
- Jun 04, 2018 Fortnightly links (63)
- May 23, 2018 Fortnightly links (62)
- May 21, 2018 A new website for the Stacks project (2)
- May 20, 2018 A website for Gerby
- May 06, 2018 Fortnightly links (61)
- Apr 22, 2018 Fortnightly links (60)
- Apr 09, 2018 My course on Hochschild (co)homology starts tomorrow
- Apr 08, 2018 Fortnightly links (59)
- Mar 30, 2018 Fortnightly links (58)
- Mar 18, 2018 Golyshev's periodic table for Fano 3-folds of rank 1
- Mar 13, 2018 Fortnightly links (57)
- Feb 27, 2018 Fortnightly links (56)
- Feb 11, 2018 Fortnightly links (55)
- Feb 01, 2018 Course announcement: Hochschild (co)homology
- Jan 28, 2018 Fortnightly links (54)
- Jan 27, 2018 Hodge numbers for complete intersections
- Jan 21, 2018 Hodge numbers for $\operatorname{M}_C(r,\mathcal{L})$
- Jan 14, 2018 Fortnightly links (53)
- Jan 05, 2018 Introducing Gerby: the tools and website
- Jan 01, 2018 Fortnightly links (52)

## 2017

- Dec 17, 2017 Fortnightly links (51)
- Dec 04, 2017 Fortnightly links (50)
- Nov 19, 2017 Fortnightly links (49)
- Nov 18, 2017 Hodge numbers for $\operatorname{Hilb}^nS$
- Nov 13, 2017 Ragnar-Olaf Buchweitz (1952–2017)
- Oct 29, 2017 Fortnightly links (48)
- Oct 15, 2017 Fortnightly links (47)
- Oct 04, 2017 Starting my postdoc
- Oct 02, 2017 Fortnightly links (46)
- Sep 17, 2017 Fortnightly links (45)
- Sep 13, 2017 Open access journals in algebraic geometry
- Sep 11, 2017 The Stacks project now uses HTTPS
- Sep 03, 2017 Fortnightly links (44)
- Aug 27, 2017 Introducing Gerby: plasTeX
- Aug 20, 2017 Fortnightly links (43)
- Aug 09, 2017 The Stacks project workshop: the aftermath
- Aug 06, 2017 Fortnightly links (42)
- Jul 23, 2017 Fortnightly links (40) and (41)
- Jun 25, 2017 Fortnightly links (39)
- Jun 14, 2017 Dimensions of partial flag varieties
- Jun 11, 2017 Fortnightly links (38)
- May 28, 2017 Fortnightly links (37)
- May 20, 2017 Fugue and the guitar
- May 14, 2017 Fortnightly links (36)
- Apr 30, 2017 Fortnightly links (35)
- Apr 16, 2017 Fortnightly links (34)
- Apr 09, 2017 On Bondal's counterexample to the Jordan-Hölder property: non-extendability
- Apr 08, 2017 On Bondal's counterexample to the Jordan-Hölder property: exceptionality
- Apr 02, 2017 Fortnightly links (33)
- Mar 26, 2017 Do you want to be my colleague?
- Mar 25, 2017 Nikita Koshkin's 24 preludes and fugues are now published
- Mar 19, 2017 Fortnightly links (32)
- Mar 05, 2017 Fortnightly links (31)
- Feb 27, 2017 Summer school: Quadratic forms and local-global principles
- Feb 19, 2017 Fortnightly links (30)
- Feb 05, 2017 Fortnightly links (29)
- Jan 25, 2017 One week left to register for the Stacks project workshop
- Jan 22, 2017 Fortnightly links (28)
- Jan 08, 2017 Fortnightly links (27)

## 2016

- Dec 26, 2016 Fortnightly links (26)
- Dec 11, 2016 Fortnightly links (25)
- Nov 30, 2016 Improved open and closed immersions in tikz-cd
- Nov 27, 2016 Fortnightly links (24)
- Nov 21, 2016 Gorenstein weighted projective spaces and Egyptian fractions
- Nov 13, 2016 Fortnightly links (23)
- Nov 08, 2016 Registration for the Stacks Project Workshop
- Nov 05, 2016 Announcing bibgetter
- Oct 30, 2016 Fortnightly links (22)
- Oct 24, 2016 Aligning table columns on a mathematical operator
- Oct 16, 2016 Fortnightly links (21)
- Oct 11, 2016 The great debate: is it del Pezzo or Del Pezzo?
- Oct 05, 2016 List of mentors for Stacks Project Workshop
- Oct 03, 2016 According to Groth. IV.22
- Oct 02, 2016 Fortnightly links (20)
- Sep 25, 2016 Live blogging the Antwerp conference (3)
- Sep 22, 2016 Live blogging the Antwerp conference (2)
- Sep 20, 2016 Live blogging the Antwerp conference
- Sep 19, 2016 Fortnightly links (19)
- Sep 11, 2016 Is it the Cartan, Coxeter or Gram matrix?
- Sep 06, 2016 Stacks Project Workshop
- Sep 04, 2016 Fortnightly links (18)
- Aug 30, 2016 Computing relations in Jacobi algebras
- Aug 26, 2016 Moving from WordPress to Jekyll
- Aug 25, 2016 Abstracts for the Antwerp conference
- Aug 21, 2016 Fortnightly links (17)
- Aug 19, 2016 Do you want to be my colleague?
- Aug 18, 2016 Two fuzzy projective lines
- Aug 17, 2016 The ICRA award goes to Greg Stevenson and Qiu Yu
- Aug 14, 2016 When is an algebraic geometer skilful enough?
- Aug 07, 2016 Fortnightly links (16)
- Jul 31, 2016 Announcing ncag.info
- Jul 23, 2016 Fortnightly links (15)
- Jul 10, 2016 Fortnightly links (14)
- Jul 07, 2016 Stacks project website bug fixing
- Jul 05, 2016 When is D(Qcoh X) compactly generated by a single perfect complex?
- Jul 02, 2016 Stacks project citations
- Jun 26, 2016 Fortnightly links (13)
- Jun 12, 2016 Fortnightly links (12)
- May 29, 2016 Fortnightly links (11)
- May 26, 2016 Alternative visualisation of the structure of the Stacks project
- May 22, 2016 On a conjecture by Novakovic
- May 15, 2016 Fortnightly links (10)
- May 11, 2016 New paper: Noncommutative quadrics and Hilbert schemes of points
- May 01, 2016 Fortnightly links (9)
- Apr 29, 2016 Do you want to be my colleague?
- Apr 22, 2016 More cheat sheets
- Apr 20, 2016 The Brauer group of Brauer-Severi varieties
- Apr 17, 2016 Fortnightly links (8)
- Apr 06, 2016 AlphaGo versus computer playback of music
- Apr 05, 2016 Non-commutative, derived and homotopical methods in geometry
- Apr 03, 2016 Fortnightly links (7)
- Mar 20, 2016 Fortnightly links (6)
- Mar 06, 2016 Fortnightly links (5)
- Feb 21, 2016 Fortnightly links (4)
- Feb 09, 2016 Genera of complete intersection curves
- Feb 07, 2016 Fortnightly links (3)
- Feb 03, 2016 The Stacks project has 5000 pages
- Jan 31, 2016 Announcement: IMAGINARY@Antwerpen
- Jan 30, 2016 Announcement: MGM@UA
- Jan 26, 2016 Nonrationality of the generic cubic fourfold
- Jan 24, 2016 Fortnightly links (2)
- Jan 10, 2016 Fortnightly links

## 2015

- Dec 28, 2015 Algebraic geometry fun facts for the festivities: Enriques surfaces are never complete intersections
- Dec 27, 2015 Algebraic geometry fun facts for the festivities: genera of complete intersection curves
- Dec 26, 2015 Algebraic geometry fun facts for the festivities: direct products of quasicoherent sheaves are not exact
- Dec 25, 2015 Algebraic geometry fun facts for the festivities: absolute flatification
- Dec 24, 2015 Algebraic geometry fun facts for the festivities: cohomology vanishing
- Dec 23, 2015 "Look ma, no Hodge theory"
- Dec 22, 2015 texloganalyser
- Dec 21, 2015 On "Towards MathJax 3.0"
- Nov 11, 2015 Simons Collaboration on Homological Mirror Symmetry
- Nov 09, 2015 Today I learned...
- Sep 26, 2015 A cheat sheet on recollements
- Sep 13, 2015 Interactive analysis of Bach's Das Wohltemperierte Klavier
- Sep 12, 2015 Linkdump: alpof
- Sep 05, 2015 Excellent notes on algebraic stacks
- Aug 19, 2015 What makes the Kronecker quiver special?
- Aug 16, 2015 Cohomology tables in Macaulay2
- Jul 29, 2015 A map of Calabi--Yau 3-folds
- Jul 28, 2015 Remote access for MathSciNet
- Jul 15, 2015 le superficie algebriche
- Jul 01, 2015 New feature for the Stacks project: detailed tag edits
- Mar 09, 2015 Works of Sasha Rosenberg
- Mar 01, 2015 A new map of Spec Z[x]
- Feb 24, 2015 Announcement for a seminar

## 2014

- Dec 07, 2014 Brute forcing first species counterpoint
- Nov 27, 2014 Examples of spectral sequences in algebra and algebraic geometry
- Nov 24, 2014 Nitpicking on Čech cohomology notation
- Nov 23, 2014 Adding an equation to the table of contents
- Nov 20, 2014 What to do if a proof is psychologically uncomfortable?
- Nov 17, 2014 Bernhard Keller won the Prix Sophie Germain
- Nov 11, 2014 How do I properly cite a preprint in `biblatex`?
- Nov 06, 2014 Software for computations in algebraic geometry
- Oct 30, 2014 Visualisation of Schubert classes in Gr(2,4) and Gr(2,5)
- Oct 30, 2014 On rational surface singularities
- Oct 23, 2014 Three filtrations on the Grothendieck ring of a scheme
- Oct 16, 2014 Only five smooth projective toric Fano surfaces
- Oct 09, 2014 What are Chern classes?
- Oct 02, 2014 Why homotopy colimits in triangulated categories are defined the way they are
- Aug 01, 2014 Comparison of topologies
- Jul 24, 2014 New feature for the Stacks project: slogans
- Jul 06, 2014 Notes on stratification of triangulated categories
- Jun 17, 2014 New version of Hodge diamonds and Serre duality tables for complete intersections
- Jun 13, 2014 Table of contents for Thomason--Trobaugh
- Jun 07, 2014 Phantom categories do exist
- Apr 25, 2014 TikZ workshop: the slides
- Apr 24, 2014 Announcement: TikZ workshop
- Apr 04, 2014 Do phantom categories exist?
- Apr 03, 2014 New feature for the Stacks project: references
- Mar 22, 2014 Serre's diagonal trick
- Mar 05, 2014 Noncommutative geometry on the arXiv
- Feb 23, 2014 Notes on depth and updates
- Jan 29, 2014 Notes on Riemann-Roch, Serre duality and Grothendieck duality
- Jan 29, 2014 Announcing a seminar
- Jan 16, 2014 A visualisation of Serre duality and Hodge diamonds

## 2013

- Dec 31, 2013 The fppf topology is generated by Zariski coverings and surjective finite locally free morphisms
- Nov 27, 2013 Modular group algebras of finite representation type
- Nov 14, 2013 Possible noncommutative progress on the standard conjectures
- Oct 25, 2013 Why Hochschild cohomology is not functorial
- Jul 30, 2013 A new website for the Stacks project: the sequel
- May 24, 2013 Every projective variety is a quiver Grassmannian: the algorithm
- Apr 20, 2013 Autour de la Géométrie Algébrique Dérivée
- Mar 13, 2013 Open and closed immersions in tikz-cd
- Feb 16, 2013 Random thoughts about Rubik's cubes
- Feb 09, 2013 GAGA in 24+epsilon tweets
- Feb 04, 2013 Categories for todos
- Jan 07, 2013 An online bibliography for the Stacks project

## 2012

- Dec 30, 2012 More 'Infinite Jest' web goodies
- Dec 15, 2012 Online view for the Stacks project
- Dec 14, 2012 An atlas of the affine line over the integers (Spec Z[x])
- Sep 14, 2012 Perfect groups of infinite commutator length: example
- Sep 11, 2012 Perfect groups of infinite commutator length: setup
- Sep 10, 2012 Personal update
- Jul 19, 2012 A new website for the Stacks project
- Jun 21, 2012 Some trivia on derived subgroups
- Jun 19, 2012 Why should I be using TeX for graphics?
- Apr 20, 2012 A Pygments lexer for GAP
- Mar 29, 2012 How to write Čech cohomology groups in LaTeX
- Mar 27, 2012 Enumerating all matrices in Jordan normal form
- Feb 09, 2012 A beamer theme for the University of Ghent
- Jan 09, 2012 The flaw in all Western music is related to the Riemann zeta function

## 2011

- Dec 18, 2011 Alternating beams for semi-quavers in Lilypond
- Dec 14, 2011 Changing \href{}{} to produce footnotes
- Dec 05, 2011 Dutch LaTeX course
- Nov 04, 2011 \uparrow and its variations are variable-sized delimiters
- Oct 30, 2011 Meanwhile at #angs@t / angs+
- Oct 06, 2011 The abc-conjecture
- Sep 25, 2011 Counterpoint in Gregorian modes
- Sep 17, 2011 Struggling with Oz
- Sep 17, 2011 Some remarks on Gregorian modes
- Aug 27, 2011 An update to dutch.lbx in babelbib
- Aug 24, 2011 How to use \thanks in memoir's titlingpage
- Aug 18, 2011 Development of the Fuxian counterpoint project is now available at GitHub
- Aug 17, 2011 Solution's to Vakil's Foundations of Algebraic Geometry
- Aug 16, 2011 Installing the Mozart Programming System
- Aug 16, 2011 Installing Strasheela
- Aug 15, 2011 Computational composition: the kick start
- Jul 23, 2011 Adding ~/.texmf to TeX Live 2011's directories, or installing beamer themes
- Jul 05, 2011 Guest post: Inheritance in Pygments' LatexFormatter
- Jun 19, 2011 Solutions to Tennison's Sheaf theory
- Jun 06, 2011 A visual exploration of the filmography of James O. Incandenza and the world of David Foster Wallace's "Infinite Jest."
- May 29, 2011 Math joke
- May 25, 2011 A LaTeX version of Mumford's impression of Spec Z[x], or some TikZ tricks
- May 08, 2011 An algorithm to determine the intersection multiplicity of two curves
- Apr 18, 2011 Alice's Adventures in Wonderland, or 3 math novels
- Mar 15, 2011 A correct implementation of the Dutch language in babelbib
- Mar 06, 2011 How to change Pygments styles and a University of Antwerp style
- Feb 26, 2011 Relative paths in multiple documents
- Feb 20, 2011 Why LaTeX beamer needs fragile when using verbatim
- Jan 05, 2011 Ska comics

## 2010

- Dec 30, 2010 Lessons learned from blogging
- Dec 27, 2010 An H-tree in TikZ
- Dec 25, 2010 Photographs of the Paris metro
- Dec 24, 2010 An extension to our \function macro: injective and surjective functions using optional parameters
- Dec 21, 2010 thmtools: a rant
- Dec 18, 2010 My good practice concerning inline mathematical formulas
- Dec 15, 2010 \twoheadrightarrow is in amssymb
- Dec 15, 2010 How to let a command automatically adapt to the current mathematical style
- Dec 12, 2010 A Turing machine in LaTeX: the follow-up
- Dec 09, 2010 This is how I feel nowadays
- Dec 06, 2010 The power of \mathclap (and \substack)
- Dec 03, 2010 A mathematical joke
- Dec 01, 2010 Article on Grothendieck and an interesting quote
- Nov 28, 2010 Wiggly text marker lines in TeX
- Nov 23, 2010 LaTeX in Vim just got a little more awesome
- Nov 22, 2010 A note on fontenc
- Nov 16, 2010 Caveat: correct spacing in quotient
- Nov 13, 2010 Automated handling of whitespace in commands using xspace
- Nov 11, 2010 Howto: Draw algebraic curves using PGF/TikZ
- Nov 08, 2010 The Stacks Project
- Nov 01, 2010 How to make the TikZ option raw output aware of segments
- Nov 01, 2010 How not to read the source of pgfplots
- Oct 24, 2010 Polynomial division
- Oct 14, 2010 Literate programming
- Oct 14, 2010 Antwerp ACM Student Chapter and Te(ch/X)Talks
- Oct 02, 2010 Direct and inverse limit in LaTeX
- Sep 13, 2010 PhilTeX
- Aug 27, 2010 Paris
- Aug 20, 2010 Ingrid Daubechies elected as president of the International Mathematical Union
- Aug 16, 2010 Introduction