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(in reverse chronological order)

**Highlighted Talks:**
(see all talks)

- Louvain-1506:
**Expansions**, Five Chaire de la Vallée-Poussin talks in Louvain-la-Neuve, Belgium, June 1-5, 2015. - CMU-1504:
**Commutators**, Carnegie Mellon University, April 2015. - Georgetown-1503:
**When does a group have a Taylor expansion?**Georgetown University, March 2015. - Hamilton-1412:
**Tangles, Wheels, Balloons**, Hamilton, December 2014. - Fields-1411: Talks at the "Legacy of Vladimir Arnold" Conference:
**Dessert: Hilbert's 13th Problem, in Full Colour**and**Finite Type Invariants of Doodles**, The Fields Institute, November 2014. - Treehouse-1410:
**The 17 Tiling Patterns: Gotta Catch 'Em All!**, Treehouse Talks, October 2014. - ClassroomAdventures-1408:
**The 17 Worlds of Planar Ants**, Classroom Adventures in Mathematics, Toronto, August 2014. - Oberwolfach-1405:
**Some very good formulas for the Alexander polynomial**Oberwolfach, May 2014. - Vienna-1402:
**A Partial Reduction of BF Theory to Combinatorics,**Vienna, February 2014. - ClassroomAdventures-1401:
**Visualizing the Fourth Dimension, and the Simplest Thing I Don't Know About It,**Classroom Adventures in Mathematics, Toronto, January 2014. - HUJI-140101:
**קשרים בארבעה מימדים והבעיה הפתוחה הפשוטה ביותר אודותם,**(Knots in Four Dimensions and the Simplest Open Problem About Them, Hebrew lecture), Jerusalem, January 2014. - Bern-131104:
**The Kashiwara-Vergne Problem and Topology,**Bern, November 2013. - Zurich-1310:
**Informal Talks on the Topology, Combinatorics, and Low and High Algebra of w-Knots,**6 talks in Zurich, October 2013. - Geneva-131024:
**Finite Type Invariants of Ribbon Knotted Balloons and Hoops,**Geneva, October 2013. - Geneva-130917:
**Trees and Wheels and Balloons and Hoops and More Later,**Geneva, September 2013. - ClassroomAdventures-1308:
**On Maps, Machines and Roaches**, Classroom Adventures in Mathematics, August 2013. - Montreal-1306:
**A Quick Introduction to Khovanov Homology,**two talks in Montreal, June 2013 (plus one more on meta-groups). - Aarhus-1305:
**(u, v, and w knots) x (topology, combinatorics, low algebra, and high algebra),**QGM Master Class, Aarhus May-June 2013. - Cambridge-1301:
**Non-Commutative Gaussian Elimination and Rubik's Cube,**Cambridge, January 2013. - Newton-1301:
**Braids and the Grothendieck-Teichmuller Group,**and**Meta-Groups, Meta-Bicrossed-Products, and the Alexander Polynomial,**the Newton Institute, January 2011. - Hamburg-1208:
**A Quick Introduction to Khovanov Homology**and**Balloons and Hoops and their Universal Finite Type Invariant, BF Theory, and an Ultimate Alexander Invariant**, two talks in Hamburg, August 2012. - Caen-1206:
**Caen Workshop on v- and w-Knotted Objects,**about 25 hours of talks over 9 days in June 2012 in Caen, France. - Oregon-1108:
**The Pure Virtual Braid Group is Quadratic,**Oregon, August 2011. - SwissKnots-1105:
**Facts and Dreams About v-Knots and Etingof-Kazhdan,**Swiss Knots 2011, Lake Thun, May 2011. - Tennessee-1103:
**Cosmic Coincidences and Several Other Stories,**Tennnessee, March 2011. - RCI-110213:
**The Hardest Math I've Ever Really Used,**Royal Canadian Institute, Toronto, February 2011. - Chicago-1009:
**From the**and*ax+b*Lie Algebra to the Alexander Polynomial and Beyond,**18 Conjectures,**Chicago, September 2010. - Montpellier-1006:
**I understand Drinfel'd and Alekseev-Torossian, I don't understand Etingof-Kazhdan yet, and I'm clueless about Kontsevich,**three talks in Montpellier, June 2010. - Goettingen-1004:
**u, v, and w-Knots: Topology, Combinatorics and Low and High Algebra**, Courant Lecture Series, Goettingen, April 2010. - Bonn-0908:
**Convolutions on Lie Groups and Lie Algebras and Ribbon 2-Knots**, Bonn, August 2009. - Trieste-0905:
**(u, v, and w knots) x (topology, combinatorics, low algebra, and high algebra)**, Trieste, May 2009. - Sandbjerg-0810:
**The Penultimate Alexander Invariant**, Sandbjerg, Denmark, October 2008. - MSRI-0808:
**Projectivization, W-Knots, Kashiwara-Vergne and Alekseev-Torossian**, MSRI, August 2008. - Fields-0709:
**A Very Non-Planar Very Planar Algebra**, The Fields Institute, September 2007. - Hanoi-0708:
**Following Lin: Expansions for Groups**, Vietnamese Academy of Science and Technology, August 2007. - Aarhus-0706:
**Algebraic Knot Theory**, Århus University, June 2007. - Kyoto-0705:
**The Virtues of Being an Isomorphism**, RIMS, Kyoto May 2007. - UofT-GS-070308:
**A Homological Construction of the Exponential Function**, Graduate Student Seminar, University of Toronto, January 2005. - Utah-0506:
**Local Khovanov Homology - Computations and Mutations**, Snowbird, Utah, June 2005 - UIUC-050311:
**I don't understand Khovanov-Rozansky homology**, University of Illinois at Urbana-Champaign, March 2005. - GWU-050213:
**I've Computed Kh(T(9,5)) and I'm Happy**, George Washington University, February 2005. - UofT-GS-050113:
**Gödel's Incompleteness Theorem**, Graduate Student Seminar, University of Toronto, January 2005. - UWO-040213:
**Probability: Fact, Fiction and Quantum**and**Khovanov Homology for Knots and Links**, University of Western Ontario, February 2004. - UofT-040205:
**"Not Knot" and "Outside In"**, University of Toronto, February 2004. - BIRS-0311:
**Introduction to Perturbative Chern-Simons Theory**and**Introduction to Khovanov Homology**, BIRS, Banff, November 2003. - Wayne-031103:
**The Unreasonable Affinity of Knot Theory and the Algebraic Sciences**, Wayne State University, November 2003. - Davis-010813:
**Algebraic Structures on Spaces of Knots**, University of California at Davis, August 2001. - HUJI-010118: , The Hebrew University, January 2001.
- Fields-010111:
**Knot Invariants, Associators and a Strange Breed of Planar Algebras**, The Fields Institute, January 2001. - MSRI-001206:
**Finite type invariants and a strange breed of planar algebras**, MSRI December 2000. - UCB-000215:
**Embedded Trivalent Graphs and an Infant Conjecture**, Berkeley, February 2000. - UMD-991029:
**On Links, Functions, Integrals and 3-Manifold Invariants**, University of Maryland, October 1999. - JHU-991027:
**The Harish-Chandra-Duflo Isomorphism is as Easy as 1+1=2**, Johns Hopkins University, October 1999. - Srni-9901:
**From Astrology to Topology via Feynman Diagrams and Lie Algebras**, Srni, January 1999.

**Talks Since November 1998:**
(172 listed, 54 highlighted).

Louvain-1506, Toronto-150514, CMU-1504, Georgetown-1503, TCDSB-150213, MUGS-1501, Hamilton-1412, Fields-1411, Treehouse-1410, ClassroomAdventures-1408, CanadaMathCamp-1407, Bannoye-1407, Oberwolfach-1405, Vienna-1402, McMaster-140130, ClassroomAdventures-1401, HUJI-140101, Grenoble-1311, Lausanne-131118, Bern-131104, Zurich-1310, Geneva-131024, Geneva-131008, Zurich-130919, Geneva-130917, ClassroomAdventures-1308, CanadaMathCamp-1308, CUMC-1307, Montreal-1306, Aarhus-1305, Singapore-1305, NhaTrang-1305, Chicago-1303, Toronto-1303, Sheffield-130206, Cambridge-1301, Oxford-130121, Imperial-130118, Newton-1301, Israel-1301, MtAllison-121013, Hamburg-1208, CanadaMathCamp-1208, Caen-1206, Regina-1206, Binghamton-1203, GWU-1203, Buffalo-1203, CanadianPerspectives-1110, StBonaventure-1110, Strasbourg-1109, Oregon-1108, Colombia-1107, Geneva-110531, SwissKnots-1105, Tennessee-1103, RCI-110213, Toronto-110110, Chicago-1009, Montpellier-1006, Toronto-1005, Goettingen-1004, Luminy-1004, UWO-100225, Fields-0911, UofT-GS-090930, Bonn-0908, HUJI-090727, Mathcamp-0907, Paris-0906, Trieste-0905, KSU-090407, Bogota-0902, PSU-090205, Northeastern-081028, Copenhagen-081009, Sandbjerg-0810, MSRI-0808, CUMC-0807, Geneva-0805, Zurich-080513, Oberwolfach-0805, Brown-071114, UofT-GS-071023, Fields-0709, Hanoi-0708, Tianjin-0707, Aarhus-0706, Kyoto-0705, TiTech-070508, Buffalo-070323, UofT-GS-070308, Columbia-070209, HUJI-061228, Uppsala-0609, UofT-0608, Istanbul-0606, Iowa-060120, HUJI-060101, GaTech-051021, UofT-051014, UQAM-051001, Oberwolfach-0506, Utah-0506, Amsterdam-050418, LSU-0504, UIUC-050311, GiftedConference-050215, GWU-050213, MASSU-050119, UofT-GS-050113, UofT-041208, York-041108, Harvard-0410, Buffalo-0410, Oporto-0407, GWU-0405, Microsoft-040413, Rochester-040402, MSU-0402, UWO-040213, UofT-040205, Queens-040123, UofT-031208, BIRS-0311, Wayne-031103, UofT-031002, UIC-030905, Warsaw-030711, Potsdam-030604, Cornell-030501, Harvard-030418, UofT-030331, Columbia-030328, JHU-0303, UNC-0302, HUJI-021230, BU-021101, UofT-021010, McMaster-021005, UQAM-020927, HUJI-020613, BIU-020320, Toronto-0202, Toronto-020211, HUJI-011104, Kyoto-0109, Calgary-010824, Davis-010813, HUJI-010118, Fields-010111, MSRI-001206, CUNY-001205, HUJI-001116, Compugen-001101, Lehigh-0006, Riverside-000429, UCB-0004, UCB-000420, CalTech-000221, UCB-000215, UCSD-000113, GaTech-991203, UMD-991029, JHU-991027, UCB-9910, UCB-990915, Srni-9901, HUJI-981203, Aarhus-9811-2, Aarhus-9811-1, BGU-981103

On first inspection, in their jars, or aquariums, or ouroboriums, they appear to be simply domesticated serpents, writhing as they do suspended in the ether. But of course, there's more to mythological creatures, even domesticated varieties, than meets the eye. Know this about the ouroborus: when one chooses to bite its own tail - a choice which sooner or later every one of its kind is destined to make - it cannot release it. It will spend the rest of its existence as a never-ending loop. It might twist and writhe and flatten and flex, but it is forever hooped.

An ouroborus in a jar on the shelf, from the Planetarium.