daniel teixeira

PhD candidate at Dalhousie University supervised by Theo Johnson-Freyd. My work revolves around higher category theory, with emphasis in (∞,∞)-categories and where they meet topological physics.

On my mind (Nov '26): (∞,∞)-categories with adjoints, unstraightening of (∞,∞)-categories, simplicial HoTT, formalization.

contact: daniel.teixeira@dal.ca

writing:

activities:

24-25 Oct 26: Cascade Topology Seminar at UBC.

19-23 Oct 26: Motivic Homotopy Theory: Connections and Applications at SLMath.

15 Oct 26: talk at the Dalhousie grad seminar about orbifolds of dyads and other chords.

7 Oct 26: talk at the Dalhousie honors seminar about high school angles.

10 Sept 26: preprint A model structure for cartesian 2-fibrations (a Matemáticas en Cono Sur 2 collaboration) is out.

Fall 26: TA for MATH 4680/5680 - Topics in Logic and Computation. The topic is Lean for Mathematics

Fall 26: reading group on simplicial type theory at Dalhousie. (organized with Hayato)

Aug-Dec 26: segunda edição do Projeto Irerê. (organizo com Thiago)

3-8 Aug 26: talk at the XXIV Encontro Brasileiro de Topologia at the Universidade Federal do Espírito Santo. slides (half-board talk)

6-17 July 26: Elliptic Objects, von Neumann Algebras, and Functorial Field Theory at the Bernoulli Center

22-26 June 26: Summer School on Homotopy Colimits at the University of Regina

15-19 June 26: talk at FMCS 2026 at St. Francis Xavier University. slides (half-board talk)

8-12 June 26: JardineFest at Western University

5-8 June 26: talk at the CT session at the 2026 CMS Summer Meeting. Homotopy Theory session coorganized with Cam and Martin.

25 May - 12 June 26: M2PI 2026. I worked on the Hummingbird project

26 May 26: talk at the III Encontro Brasileiro em Teoria das Categorias. slides

Summer 26: teaching MATH 2001 - Intermediate Calculus. With the online setup in mind, we used an specifications grading system.

16-18 Mar 26: FRG workshop on higher categories and geometry in Chicago. more

3 Mar 26: informal discussion about a categorified Whitehead theorem. notes

Feb-Jun 26: primeira edição do Projeto Irerê. (organizado com Thiago)

10 Jan 26: Dal Math Career Day. (coorganized with Thiago)

Winter 26: reading group on (∞,∞)-categories at Dalhousie

6-8 Dec 25: 2025 CMS Winter Meeting in Toronto

21 Oct 25: talk at the ATCAT about categories as directed spaces. notes

20 Oct 25: talk at the Dalhousie graduate seminar about sines of rational fractions of π. notes

17-18 Oct 25: MSCS 2025 at Cape Breton University.

15 Oct 25: we played the Natural Number Game at the Dalhousie honors seminar.

7 Oct 25: informal talk about reflective localizations. notes

18 Sept 25: notes from the STOAT 2024 on the arXiv.

13-20 Sept 25: Heidelberg Laureate Forum

1-12 Sept 25: Higher Structures school and workshop at the University of Hamburg. gong show notes

Fall 25: TA for MATH 1000 - Differential & Integral Calculus I. These tutorials were good, see here for their workflow.

30 Jul - 2 Aug 25: teaching Scratch at the Dalhousie Indigenous Math Camp 2025.

8 Jul 25: preprint Mutual Influence of Symmetries and Topological Field Theories (joint with Matthew Yu) is out.

6-11 Jul 25: teaching Scratch at the BEA Math Camp. Check out our students' projects here!

30 Jun - 3 Jul 25: Workshop on QFT and Topological Phases via Homotopy Theory and Operator Algebras at Harvard.

18 Jun 25: talk at the FMCS 2025 about a model structure for 2-fibrations. notes

09 Jun 25: talk at the 2025 CMS Summer Meeting about monoidal homotopy bicategories. notes

Summer 25: teaching MATH 1030 - Matrix Theory & Linear Algebra I.

4 Apr 25: judge at the Halifax Sci-Tech expo.

27 Mar 25: judge at the South Shore regional science fair.

11 Mar 25: talk at the ATCAT about monoidal homotopy bicategories. (notes lost to the void)

Winter 25: teaching MATH 2040 - Matrix Theory & Linear Algebra II.

27 Nov 24: talk at the Dalhousie honors seminar about catastrophes and higher categories. slides

26 Nov 24: talk at the ATCAT about a model structure for 2-fibrations. notes

11 Nov 24: talk at the UIUC Graduate Student Homotopy Theory Seminar about H^q(K(G,n),Z/2) and monoidal groupoids.

2-3 Nov 24: Midwest Topology Seminar at the University of Chicago.

Oct-Nov 24: stay at UIUC under supervision of Dan Berwick-Evans.

16 Oct 24: talk at the eCHT Kan seminar Fall 2024 about this paper. notes

14-19 Oct 24: stay at the Perimeter Institute.

2 Oct 24: informal conversation about 2-fibrations. notes

1 Oct 24: talk at the Dalhousie graduate seminar about the Eckmann-Hilton argument in higher dimensions. notes

23-27 Sept 24: Scottish Talbot on fusion 2-categories. notes by Adrien

8 Jul - 2 Aug 24: School on Univalent Mathematics at the University of Minnesota.

20-25 Jul 24: two talks at the Dalhousie Math Camp about Geometry & Topology.

7-12 Jul 24: teaching Scratch at the BEA Math Camp. Check out the student projects here!

3-14 Jun 24: Thematic Program in Field Theory and Topology at the University of Notre Dame. poster

20-24 May 24: Atlantic TQFT Spring School 2024 at the Memorial University of Newfoundland.

29 Apr 24: informal conversation about relating Morse theory, catastrophes, and higher categories. notes

18-22 Mar 24: Higher Categorical Tools for Quantum Phases of Matter at Perimeter Institute.

18-23 Feb 24: Matemáticas en Cono Sur 2 at UdelaR, Montevideo, working in the 2-fibrations group.

Winter 24: teaching a section of MATH 1215 - Life Sciences Calculus.

30 Nov 23: I passed my comprehensive exam. You can see details about my thesis project here.

17 Nov 23: talk at the USP categories seminar about ladders of 2-categories. notes (in Portuguese)

Fall 23: Inclusive STEM Teaching course by the CIRTL Network. At Dalhousie, Sarah Chisholm organized in-person meetings.

Fall 23: online (∞,2)-workshop organized by Moser, Rasekh and Rovelli.

1 Nov 23: talk at the Dalhousie honors seminar about category theory. notes

26 Oct 23: genesis of the spectral sequences reading group at Dalhousie. details

14 Oct 23: talk at the MSCS 2023 about ladders of 2-categories. slides

6 Oct 23: talk at the Dalhousie graduate seminar about the toric code.

3-8 Sept 23: GCS2023 summer school at Les Diablerets, Switzerland.

19-23 Jun 23: École d'été sur les fibrés et leurs connexions at the Université de Sherbrooke.

1-5 May 23: Atlantic TQFT spring school at Wolfville, NS.

8 Mar 23: talk at the Dalhousie honors seminar about the topology of our spacetime. notes

21 Sept 22: talk at the TQFT reading group about the Morita bicategory. notes

22 Feb 22: I defended my master's thesis! Go check it out. 🇧🇷

Dalhousie University is in Mi'kma'ki, the ancestral and unceded territory of the Mi'kmaq.