| © | Dror Bar-Natan: Academic Pensieve: | Random |
Recent prefixes: Afeke VanDerVeen Abbasi Frohlich Dror Gaudreau Scherich Munasinghe Meusburger Dancso ThurstonD Bellingeri Chterental Fresse Ens Stein
All prefixes: 08401 09240 10_327 11_1100 12_240 12_267 14_1100 15-344 15-475 16-1750 16-475 1617-257 17-1750 18-327 18S-AKT AKT09 AKT14 AKT17 Aarhus Abbasi Accra2010 Afeke Alekseev Alexakis Alhawaj Andersen Antolin Archibald BCHKW Bazett Beliakova Bellingeri Bettencourt Bigelow Blazejewski Boden Brin Brochier BrownF Bryden Burgos Caen Carrasco Carter Cattaneo Cheng Chterental Chu Cimasoni Conant Costantino Costello Dalvit Dancso Dema Deng Dolgushev Dror Enriquez Ens Etingof Faifman Fiedler Filmus Freedman Fresse Frohlich Frohman Furusho Gadanidis Gallagher Gaudreau Getzler Godin Gualtieri Halacheva Henriques Hillman Hirasawa Hoell Humbert Hurd Itai Izmaylov JohnsonFreyd KAL Kalka Kamnitzer Karshon Kashaev Katz Kauffman Kazhdan KhesinA Khovanov Kirk Koytcheff Kricker Kuno Kuperberg Lai Lambrechts LazyKnots Le LeD Ledvinka LeeP Leung LiBland LicataT Martel Martins Masbaum Massuyeau Matviichuk McKay McLellan Medabalimi Meusburger Mirny MorganS Morrison Morton-Ferguson Moskovich Mracek Munasinghe Naef Nandakumar Nikolaev Olah Orr Overbay Papakonstantinou Peng Penneys PolyPoly-1605 Polyak Putyra Ramakrishna Rasmussen Raynor Reed Remenik Reshetikhin RobertsonM Roukema Rushworth Samuelson Sazdanovic Schaveling Scherich Schneps Sela Selmani Severa Smirnov Spreer Stein Sternberg SummerHomology2017 Thimotheus ThurstonD ToledanoLaredo Tsimerman VanDerVeen Vaughan Vergne VideoClub Vo WangH Willwacher Winter Yampolsky Yetter ZeilbergerN Zhang Zibrowius Zung deSilva wClips
| Date-Time / Prefix | Comment |
What? A collection of Blackboard Shots (7145, right now, with 180 prefixes), mostly taken
in my office using a ceiling-mounted web camera.
Why? Mostly for my own use and for the use of the other people with whom I share blackboard space. And it is public because the easiest way to make something viewable to a number of people is to make it viewable to the whole world. Oh no! If you found your handwriting here and you don't like it, please let me know and the relevant shot(s) will be removed, no questions asked. How? A ceiling-mounted Logitech QuickCam Pro 9000 web camera is permanently pointed at my blackboard and connected via USB to this web server. The script bbs.php initiates a capture (using luvcview; hit "s" to shoot and "q" to quit), prompts for a file name prefix and a comment, and runs make. The makefile runs MakeDatabase.php (if necessary) to update the ShotDatabase.php. The latter file is used by index.php, which is this page, and also by show.php, used to display individual shots. The makefile also updates bbs.zip, which contains all the above mentioned scripts as well as common.php, showprefix.php, loadnew.php, random.php, the JavaScript actions.js, and the icon bbs.jpg. Finally, $\TeX$-like rendering uses MathJax (automatic on all pages but this one). Exceptions. Some shots are taken by other means and are added manually or using loadnew.php. |
|---|---|---|
| 210415-160909 / Afeke | More cohomology computations. | |
| 210208-164014 / Afeke | Cap products (2). | |
| 210208-163929 / Afeke | Cap products. | |
| 201211-153735 / Afeke | The twisted homology of $\partial X$. | |
| 201105-173823 / Afeke | Reading Kirk's email (2). | |
| 201105-170312 / Afeke | Reading Kirk's email. | |
| 201020-161550 / Afeke | Homological representations (2). | |
| 201020-161519 / Afeke | Homological representations. | |
| 200811-165033 / Afeke | A split sequence? | |
| 200729-155915 / Afeke | Crash recovery. | |
| 200724-160451 / Afeke | A crucial statement in Kassel-Turaev (6). | |
| 200720-154713 / Afeke | A crucial statement in Kassel-Turaev (5). | |
| 200720-154633 / Afeke | A crucial statement in Kassel-Turaev (4). | |
| 200719-213611 / VanDerVeen | $t$ and $w$ generate the centre. | |
| 200717-173256 / VanDerVeen | Abbasi's argument. | |
| 200717-173027 / Abbasi | A short proof of McCool's theorem (3). | |
| 200717-173026 / Abbasi | A short proof of McCool's theorem (2). | |
| 200717-173025 / Abbasi | A short proof of McCool's theorem. | |
| 200715-155330 / Afeke | A crucial statement in Kassel-Turaev (3). | |
| 200714-145937 / Frohlich | Proofs of the Weyl commutation relations (2). | |
| 200714-145936 / Frohlich | Proofs of the Weyl commutation relations. | |
| 200714-125831 / Dror | Verifying the Heisenberg R-matrix. | |
| 200713-171423 / Gaudreau | uB injects into vB. | |
| 200713-160252 / Scherich | Long for w-braids. | |
| 200710-180818 / VanDerVeen | Traces. | |
| 200709-173838 / Afeke | A crucial statement in Kassel-Turaev (2). | |
| 200708-160203 / Frohlich | Are traces trascendental? | |
| 200703-175526 / VanDerVeen | Zipping quadratics and pairing exterior powers. | |
| 200703-160731 / Afeke | A crucial statement in Kassel-Turaev. | |
| 200702-161027 / Frohlich | The Halacheva trace. | |
| 200630-181150 / Abbasi | Basis conjugating automorphisms are generated by $\sigma_{ij}$ (2). | |
| 200630-181149 / Abbasi | Basis conjugating automorphisms are generated by $\sigma_{ij}$. | |
| Date-Time / Prefix | Comment | |
| 200630-181026 / VanDerVeen | Co-invariants, partial traces. | |
| 200627-114335 / Abbasi | Wormholes on $S^3$ (2). | |
| 200627-114334 / Abbasi | Wormholes on $S^3$. | |
| 200626-180156 / VanDerVeen | Mixed-direction homomorphisms. | |
| 200626-160403 / Frohlich | Partial traces. | |
| 200626-132922 / Afeke | $H_1({\mathbb R}^2,{\mathbb Z}^2)$. | |
| 200626-132921 / Afeke | The map $\pi_1\to H_1$ is homomorphic (3). | |
| 200625-171633 / Munasinghe | Understanding $sl_{2+}^\epsilon$. | |
| 200621-180015 / VanDerVeen | Heisenberg calculus (2). | |
| 200621-180014 / VanDerVeen | Heisenberg calculus. | |
| 200621-160318 / Dror | Switching to central variables. | |
| 200619-171742 / Scherich | Combing braids. | |
| 200619-171741 / Scherich | Free groups in virtual braid groups. | |
| 200619-160001 / Abbasi | Towards a proof of McCool's theorem (7). | |
| 200619-160000 / Abbasi | Towards a proof of McCool's theorem (6). | |
| 200619-155959 / Abbasi | Towards a proof of McCool's theorem (5). | |
| 200618-180337 / VanDerVeen | Spinner challenge. | |
| 200618-175701 / VanDerVeen | Composition for O/U tangles. | |
| 200618-160602 / Munasinghe | A genus 2 surface. | |
| 200618-100914 / Meusburger | OU tangles and Hopf words. | |
| 200617-134608 / Afeke | The map $\pi_1\to H_1$ is homomorphic (2). | |
| 200616-182321 / Abbasi | Towards a proof of McCool's theorem (4). | |
| 200616-182320 / Abbasi | Towards a proof of McCool's theorem (3). | |
| 200616-182319 / Abbasi | Towards a proof of McCool's theorem (2). | |
| 200616-182318 / Abbasi | Towards a proof of McCool's theorem. | |
| 200615-194307 / Scherich | The Artin representation. | |
| 200615-172542 / Scherich | Long's $\rho^+$ construction (2). | |
| 200615-153139 / Afeke | The map $\pi_1\to H_1$ is homomorphic. | |
| 200612-182124 / VanDerVeen | Hopf quandles? | |
| 200612-154042 / Frohlich | Minor identities and Plucker coordinates. | |
| 200611-161506 / Abbasi | Gauss diagrams, w-braids. | |
| 200611-155616 / Munasinghe | A representation theory for ${\mathfrak{g}}_\epsilon^+$? | |
| Date-Time / Prefix | Comment | |
| 200610-183444 / Scherich | Long's $\rho^+$ construction. | |
| 200610-170726 / Afeke | Back to $\tilde{H}$ (7). | |
| 200610-170702 / Afeke | Back to $\tilde{H}$ (6). | |
| 200610-091024 / Dancso | A new(?) approach for solving KV degree by degree. | |
| 200609-175618 / VanDerVeen | Proof of connectivity. | |
| 200608-155824 / Afeke | Back to $\tilde{H}$ (5). | |
| 200603-084840 / Dancso | Expansions for acyclic tangles (3). | |
| 200603-084839 / Dancso | Expansions for acyclic tangles (2). | |
| 200601-170137 / Frohlich | Alexander Half Density and palindromicity. | |
| 200601-153318 / Afeke | Back to $\tilde{H}$ (4). | |
| 200601-100322 / Dror | Searching for the perfect OU tangle / VCD. | |
| 200529-165625 / Abbasi | Proof of injectivity (5). | |
| 200529-165624 / Abbasi | Proof of injectivity (4). | |
| 200529-165623 / Abbasi | Proof of injectivity (3). | |
| 200529-165622 / Abbasi | Proof of injectivity (2). | |
| 200529-165621 / Abbasi | Proof of injectivity. | |
| 200529-105142 / Scherich | Generating the augmentation ideal. | |
| 200529-063354 / Dancso | Expansions for acyclic tangles. | |
| 200527-160353 / Afeke | Back to $\tilde{H}$ (3). | |
| 200525-154821 / Afeke | Back to $\tilde{H}$ (2). | |
| 200525-154403 / Afeke | Back to $\tilde{H}$. | |
| 200523-193626 / Dror | Asymptotic Expansions (2). | |
| 200523-193625 / Dror | Asymptotic Expansions. | |
| 200523-193429 / VanDerVeen | Z is central. | |
| 200519-163033 / Abbasi | Conjugators (2). | |
| 200519-162504 / Abbasi | Conjugators. | |
| 200519-150133 / Gaudreau | Bracelets. | |
| 200519-145927 / Gaudreau | $F=G^2$. | |
| 200518-195509 / Dror | Cinnamon Rolls with Filling. | |
| 200518-155434 / Afeke | The n-puncture case. | |
| 200515-165502 / Abbasi | Proving Artin's theorem (2). | |
| 200515-165501 / Abbasi | Proving Artin's theorem. | |
| Date-Time / Prefix | Comment | |
| 200515-145722 / Gaudreau | Reading Ito-Sakurai arXiv:2004.14785. | |
| 200514-081535 / Dror | Garside squared. | |
| 200513-170219 / Afeke | The relations between the $\alpha_n$'s (2). | |
| 200513-170218 / Afeke | The relations between the $\alpha_n$'s. | |
| 200513-160010 / Dror | The Golden Horseshoe. | |
| 200512-105355 / Dror | Cinnamon Rolls. | |
| 200510-195225 / Dror | A multi-diamond case. | |
| 200508-183718 / VanDerVeen | Diamonds (2). | |
| 200508-183717 / VanDerVeen | Diamonds. | |
| 200508-165606 / Dror | More shtrudels. | |
| 200507-172501 / Frohlich | Planar algebras and planar graphs (2). | |
| 200507-172500 / Frohlich | Planar algebras and planar graphs. | |
| 200507-172329 / Dror | Shielding from R1/R2. | |
| 200506-181422 / VanDerVeen | Divisibility and overhangs. | |
| 200506-145051 / Gaudreau | All cut systems are equivalent (2). | |
| 200506-144914 / Gaudreau | All cut systems are equivalent. | |
| 200505-163633 / Abbasi | The Artin representation. | |
| 200505-150712 / ThurstonD | The Extraction Graph. | |
| 200504-165430 / Frohlich | Circle packings, Riemann mappings, and badly drawing knots. | |
| 200504-165429 / Dror | A simple extraction graph. | |
| 200504-165428 / Dror | Long diamonds (4). | |
| 200504-150105 / Afeke | The Abelianization of a kernel (6). | |
| 200504-113848 / Dror | Long diamonds (3). | |
| 200503-151147 / Dror | Long diamonds (2). | |
| 200503-151146 / Dror | Long diamonds. | |
| 200501-164439 / Scherich | OU and VCDs. | |
| 200430-165659 / Bellingeri | Mapping class groups and graphs. | |
| 200430-165512 / Dror | Chterental's counter(?)-example (2). | |
| 200429-163709 / Afeke | The Abelianization of a kernel (5). | |
| 200429-135311 / Dror | Chterental's counter(?)-example. | |
| 200429-124522 / Frohlich | Braid-like and cyclic R-moves. | |
| 200428-210337 / Dancso | The injectivity of $\bar{\Gamma}$ and the Diamond Lemma (2). | |
| Date-Time / Prefix | Comment | |
| 200428-210336 / Dancso | The injectivity of $\bar{\Gamma}$ and the Diamond Lemma. | |
| 200428-141031 / Dror | Another divisibility case. | |
| 200426-140132 / Dror | A bug in the divisibility lemma (2). | |
| 200425-195059 / Dror | A bug in the divisibility lemma. | |
| 200425-192517 / Chterental | Some diamonds (3). | |
| 200425-173535 / Chterental | Some diamonds (2). | |
| 200425-172053 / Chterental | Some diamonds. | |
| 200425-111054 / Gaudreau | Kamada's construction (3). | |
| 200425-111053 / Dror | Lemmas about crossing number. | |
| 200424-160332 / Frohlich | Random. | |
| 200424-150653 / Scherich | A multivariable LKB? | |
| 200424-150652 / Dror | Dealing with R1 (2). | |
| 200424-150651 / Dror | Dealing with R1. | |
| 200423-171420 / Afeke | The Abelianization of a kernel (4). | |
| 200423-171419 / Afeke | Implementing Fox derivatives. | |
| 200422-151530 / Frohlich | Yarn balls and complexity. | |
| 200421-180229 / VanDerVeen | The Diamond Lemma. | |
| 200420-095233 / Dror | R1 issues. | |
| 200417-180125 / VanDerVeen | Riemann mappings and mapping-classs-vector-fields. | |
| 200417-170148 / Afeke | Back to $\tilde{H}$. | |
| 200417-170053 / Afeke | The Abelianization of a kernel (3). | |
| 200417-165539 / Afeke | The Abelianization of a kernel (2). | |
| 200417-165412 / Dror | $\beta|T$. | |
| 200415-170946 / Afeke | The Abelianization of a kernel. | |
| 200415-142703 / Dror | Every UO fixing process terminates. | |
| 200414-182305 / VanDerVeen | Aiming to separate vOU tangles with quantum invariants. | |
| 200414-124207 / Dror | A possible problem case. | |
| 200411-180721 / VanDerVeen | Virtual surgeries. | |
| 200411-144200 / Afeke | $\tilde{H}$ in Kassel-Turaev 3.2.1 (2). | |
| 200408-181534 / VanDerVeen | Random | |
| 200407-152413 / Afeke | $\tilde{H}$ in Kassel-Turaev 3.2.1. | |
| 200405-185919 / VanDerVeen | The injectivity of PvB->OU, following Chterental (3). | |
| Date-Time / Prefix | Comment | |
| 200405-185918 / VanDerVeen | The injectivity of PvB->OU, following Chterental (2). | |
| 200405-185917 / VanDerVeen | The injectivity of PvB->OU, following Chterental. | |
| 200405-152214 / Dror | Uniqueness of OU forms? | |
| 200404-172259 / Gaudreau | Kamada's construction (2). | |
| 200404-172258 / Gaudreau | Kamada's construction. | |
| 200404-150338 / Afeke | Relative homology (2). | |
| 200404-150149 / Afeke | Relative homology. | |
| 200403-160356 / Dror | Reductive OU tangles (2). | |
| 200403-160355 / Dror | Reductive OU tangles. | |
| 200401-151306 / Scherich | An up-then-down braid equivalence. | |
| 200401-151305 / Dror | Random (2). | |
| 200330-192515 / VanDerVeen | Associators and 6j symbols. | |
| 200330-192432 / VanDerVeen | Universal $sl_2$ projectors. | |
| 200330-192229 / VanDerVeen | OU tangles and braids. | |
| 200330-174054 / Dror | Random. | |
| 200330-160014 / Afeke | Back to Kassel-Turaev 3.2.1 (3). | |
| 200330-155613 / Afeke | Back to Kassel-Turaev 3.2.1 (2). | |
| 200330-152542 / Afeke | Back to Kassel-Turaev 3.2.1. | |
| 200329-131536 / Dror | An up-then-down braid relation. | |
| 200328-154555 / Afeke | The intersection form (2). | |
| 200328-153721 / Afeke | The intersection form. | |
| 200327-194535 / VanDerVeen | Connected diagrams, 1PI. | |
| 200327-194405 / VanDerVeen | The Sweedler Algebra. | |
| 200327-160234 / Afeke | The boundary of an intersection (2). | |
| 200327-160233 / Dror | Random. | |
| 200324-154112 / Afeke | The boundary of an intersection. | |
| 200323-210224 / Dror | To do. | |
| 200321-161801 / Dror | Debugging UOFix.nb and CountVPB.nb (2). | |
| 200321-161800 / Dror | Debugging UOFix.nb and CountVPB.nb. | |
| 200320-161700 / Afeke | Kassel-Turaev Section 3.2.1 (2). | |
| 200320-155143 / Afeke | Kassel-Turaev Section 3.2.1. | |
| 200319-194117 / VanDerVeen | UOFix.nb conventions. | |
| Date-Time / Prefix | Comment | |
| 200319-171019 / Frohlich | Conversion between the BV trace and the H trace (2). (more...) | |
| 200319-171018 / Frohlich | Conversion between the BV trace and the H trace. | |
| 200316-043626 / Dror | UOFix conventions. | |
| 200313-012827 / Dror | Failing slide moves (2). | |
| 200313-012826 / Dancso | am, bm, swab; surgeries. | |
| 200312-190540 / VanDerVeen | Misc. | |
| 200312-002719 / Dancso | OU and lazy loops. | |
| 200311-203105 / Dror | Failing slide moves. | |
| 200311-190547 / Afeke | Reading Kirk's email (3). | |
| 200311-190226 / Afeke | Reading Kirk's email. | |
| 200311-190225 / Afeke | Reading Kirk's email (2). | |
| 200310-182912 / Frohlich | The relation between DoPeGDO and $\Gamma$. | |
| 200310-182911 / Frohlich | Linking numbers and traces. | |
| 200306-002621 / Dancso | OU and Enriquez. | |
| 200305-175134 / Afeke | Poincare Duality (2). | |
| 200305-170258 / Frohlich | Setting up the trace equations. | |
| 200304-165010 / Gaudreau | An issue with braid parities. | |
| 200303-175834 / VanDerVeen | Smallness. | |
| 200303-165933 / Afeke | Poincare Duality. | |
| 200302-222448 / Dancso | Degree by degree twisting. | |
| 200302-015418 / Dancso | The Enriquez universal space. | |
| 200226-131424 / Afeke | Supervisory meeting. | |
| 200226-121732 / Frohlich | Supervisory meeting. | |
| 200225-125253 / Gaudreau | Supervisory meeting. | |
| 200219-123606 / Fresse | Quantization of Poisson algebras (2). | |
| 200219-122454 / Fresse | Quantization of Poisson algebras. | |
| 200219-114438 / Fresse | Associated graded and cohomology. | |
| 200218-140232 / Ens | Extending degree by degree (2). | |
| 200218-133719 / Ens | Extending degree by degree. | |
| 200218-122812 / Fresse | Braidors and associators (2). | |
| 200218-112646 / Fresse | Braidors and associators. | |
| 200217-151739 / Afeke | Poincare duality (6). | |
| Date-Time / Prefix | Comment | |
| 200217-145718 / Afeke | Poincare duality (5). | |
| 200217-143014 / Stein | Gauss diagram invariants for links. | |
| 200216-120117 / Gaudreau | Slits and slides. | |
| 200211-131421 / Afeke | Poincare duality (4). | |
| 200211-131325 / Afeke | Poincare duality (3). | |
| 200211-131236 / Afeke | Poincare duality (2). | |
| 200211-131200 / Afeke | Poincare duality. | |
| 200211-130942 / Afeke | Compositions in homological representations. | |
| 200211-120341 / Frohlich | Co-invariants and traces (2). | |
| 200206-092914 / VanDerVeen | $DPG_n$. | |
| 200205-142821 / Frohlich | Co-invariants and traces. | |
| 200205-091751 / VanDerVeen | Affine Lie algebras. | |
| 200205-075527 / VanDerVeen | R2b, R2c, and (left-)(right-)(full-) Hopf algebras. | |
| 200204-121538 / Afeke | Computing the braid action. | |
| 200128-213110 / Frohlich | Finding the $PR^4$ syzygies (3). | |
| 200128-131445 / Afeke | A basis for $H^1(X_0,p;F)$ (7). | |
| 200128-105755 / VanDerVeen | Towards a Seifert formula. | |
| 200127-113252 / Frohlich | Finding the $PR^4$ syzygies (2). | |
| 200127-105531 / Schaveling | Inverting perturbatively, the dihedral symmetry group. | |
| 200122-130202 / Afeke | A basis for $H^1(X_0,p;F)$ (6). | |
| 200122-125435 / Afeke | A basis for $H^1(X_0,p;F)$ (5). | |
| 200122-123958 / Afeke | A basis for $H^1(X_0,p;F)$ (4). | |
| 200122-115708 / Frohlich | Finding the $PR^4$ syzygies. | |
| 200122-115707 / Frohlich | Computing $PR^4$ homology. | |
| 200122-081653 / VanDerVeen | The automorphism group of $gl_{n+}^\epsilon$. | |
| 200116-163137 / VanDerVeen | A representation of $sl_{2+}^\epsilon$. | |
| 200116-163136 / VanDerVeen | The cyclic structure of $gl_{n+}^\epsilon$. | |
| 200115-110130 / VanDerVeen | The general form of a Seifert formula. | |
| 200114-100500 / Schaveling | Quantizing $sl_n$ (3). | |
| 200114-100455 / Schaveling | Quantizing $sl_n$ (2). | |
| 200114-100447 / Schaveling | Quantizing $sl_n$. | |
| 200114-100437 / Schaveling | $sl_3$ computations (6). | |
See All Shots.