BEGIN:VCALENDAR VERSION:2.0 PRODID:-// - ECPv6.16.3//NONSGML v1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH X-ORIGINAL-URL:https://aarms.math.ca X-WR-CALDESC:Events for REFRESH-INTERVAL;VALUE=DURATION:PT1H X-Robots-Tag:noindex X-PUBLISHED-TTL:PT1H BEGIN:VTIMEZONE TZID:UTC BEGIN:STANDARD TZOFFSETFROM:+0000 TZOFFSETTO:+0000 TZNAME:UTC DTSTART:20220101T000000 END:STANDARD END:VTIMEZONE BEGIN:VTIMEZONE TZID:America/Halifax BEGIN:DAYLIGHT TZOFFSETFROM:-0400 TZOFFSETTO:-0300 TZNAME:ADT DTSTART:20220313T060000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0300 TZOFFSETTO:-0400 TZNAME:AST DTSTART:20221106T050000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:-0400 TZOFFSETTO:-0300 TZNAME:ADT DTSTART:20230312T060000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0300 TZOFFSETTO:-0400 TZNAME:AST DTSTART:20231105T050000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:-0400 TZOFFSETTO:-0300 TZNAME:ADT DTSTART:20240310T060000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0300 TZOFFSETTO:-0400 TZNAME:AST DTSTART:20241103T050000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTART;TZID=UTC:20231129T153000 DTEND;TZID=UTC:20231129T163000 DTSTAMP:20260611T184459 CREATED:20231124T122206Z LAST-MODIFIED:20231124T122206Z UID:7462-1701271800-1701275400@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Speaker: Jordan Barrett\, Toronto Metropolitan University\nTitle: Graph burning\, the burning number conjecture\, and burning density \nAbstract: Graph burning is a discrete time process on a graph that acts as a simple model for the spread of social contagion in a network. Graph burning was introduced by Bonato\, Janssen and Roshanbin in 2014\, and with this introduction came the now famous “burning number conjecture”. In the first half of my talk\, I will introduce graph burning and give a brief overview of the progress made towards the burning number conjecture. Then\, for the remainder of the talk\, I will introduce a variation of graph burning in which the graph grows over time. In this variation\, if the graph grows fast enough then we may never be able to burn all of the vertices at any given time. We are instead interested in the “burning density”\, i.e.\, the limiting ratio of burning vertices to all vertices. The talk will conclude with some new results by Gunderson\, Nir\, Pralat\, and myself\, classifying the obtainable burning densities on growing grid-graphs. \nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-7/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20231124 DTEND;VALUE=DATE:20231125 DTSTAMP:20260611T184459 CREATED:20230922T153457Z LAST-MODIFIED:20230922T153847Z UID:7316-1700784000-1700870399@aarms.math.ca SUMMARY:University of New Brunswick Data Challenge 2023 DESCRIPTION:The UNB Data Challenge 2023 will bring together two competitive tracks\, Data Visualization (8th Annual)\, and Data Analytics (4th Annual) on Nov. 24\, 2023\, in a virtual format! Take up the challenge and demonstrate the power of data.\nParticipants and teams will have the chance to showcase their ability to tell a story driven by data in unique competitive formats. Teams can participate in both tracks. It is an ideal setting for citizens to get engaged\, meet leaders in academia\, government\, and private organizations\, and explore the world of data science. URL:https://aarms.math.ca/event/university-of-new-brunswick-data-challenge-2023/ LOCATION:University of New Brunswick (Fredericton Campus)\, Fredericton\, New Brunswick\, Canada CATEGORIES:AARMS outreach events END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20231122T153000 DTEND;TZID=UTC:20231122T163000 DTSTAMP:20260611T184459 CREATED:20231118T113007Z LAST-MODIFIED:20231118T113007Z UID:7454-1700667000-1700670600@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Speaker:  Santiago Guzman-Pro\, TU Dresden\nTitle:          Forbidden Tournaments and the Orientation (Completion) Problem\n\nAbstract:   For a fixed finite set of  oriented graphs F\,  the F-free  orientation problem asks\nwhether a given finite undirected graph G has an F-free orientation\, i.e.\, whether the edges\nof  G  can be  oriented so that the  resulting  oriented  graph does not contain  any oriented\ngraph from F as an oriented (induced) subgraph. It was first noted by Bang-Jensen\, Huang\,\nand Prisner that when F is a set of oriented paths on 3 vertices\, this problem easily reduces\nto 2-SAT\, and thus is solvable in polynomial-time. This was later extended to sets of oriented\ngraphs on 3 vertices (G.P.\ and Hernández-Cruz 2017). Towards a complete understanding\nof the complexity of the F-free orientation problem\,  we consider the case when  F is a set of\nfinite  tournaments.     We prove that  for every  such  F\,  this problem is in P or NP-complete.Specifically\, we show that either the F-free orientation problem can be reduced (in polynomial-\ntime) to a system of Boolean linear equations\, or the F-free orientation problem is NP-complete.\nThis  dichotomy result is  accompanied  by a  classification  statement  which\, given a set of\ntournaments  F\,   allows  us  to decide  whether  the  F-free  orientation  problem  is in  P  or\nNP-complete. We reduce this classification task to a complete complexity classification of the\norientation completion problem for F\, which is the variant of the problem above where the input\nis a partially oriented graph instead of an undirected graph\, introduced by Bang-Jensen\, Huang\,\nand Zhu (2017). Our proof uses results from the theory of constraint satisfaction\, and a result\nof Agarwal and Kompatscher (2018) about infinite permutation groups and transformation monoids.\n\nThis is joint work with Manuel Bodirsky. URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-6/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20231101T153000 DTEND;TZID=UTC:20231101T163000 DTSTAMP:20260611T184459 CREATED:20231028T105516Z LAST-MODIFIED:20231028T105516Z UID:7402-1698852600-1698856200@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Detecting (Di)Graphical Regular Representations \nSpeaker: Joy Morris\, U. Lethbridge \nAbstract: Graphical and Digraphical Regular Representations (GRRs and DRRs) are a concrete way to visualise the regular action of a group\, using (di)graphs. More precisely\, a GRR or DRR on the group $G$ is a (di)graph whose automorphism group is isomorphic to the regular action of $G$ on itself by right-multiplication.\n\nFor a (di)graph to be a DRR or GRR on $G$\, it must be a Cayley (di)graph on $G$. Whenever the group $G$ admits an automorphism that fixes the connection set of the Cayley (di)graph setwise\, this induces a nontrivial graph automorphism that fixes the identity vertex\, which means that the (di)graph is not a DRR or GRR. Checking whether or not there is any group automorphism that fixes a particular connection set can be done very quickly and easily compared with checking whether or not any nontrivial graph automorphism fixes some vertex\, so it would be nice to know if there are circumstances under which the simpler test is enough to guarantee whether or not the Cayley graph is a GRR or DRR. I will present a number of results on this question.\n\n\nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n  URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-5/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20231018T153000 DTEND;TZID=UTC:20231018T163000 DTSTAMP:20260611T184459 CREATED:20231012T115001Z LAST-MODIFIED:20231012T223528Z UID:7376-1697643000-1697646600@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Two short talks by grad students Alex Clow and William Kellough. ‘Live’ viewing in Chase 227 for those at Dalhousie. \nTalk 1:\nAlex Clow\, Simon Fraser University\nPolynomially Bounding the Oriented Chromatic Number in Euler Genus \nIn this talk we consider the oriented chromatic number of graphs with bounded Euler genus. In particular\, we present our proofs that the oriented chromatic number is at most $g^{6400}$ for sufficiently large $g$ and at least $\Omega((\frac{g^2}{\log g})^{1/3})$. This is a major improvement over the previous best upper bound which is exponential in genus. We conclude the talk by discussing directions for future study. Joint work with Peter Bradshaw and Jingwei Xu from the University of Illinois at Urbana Champaign. \nTalk 2:\nWilliam Kellough\, Memorial University\nHow to Catch a Cheating Robber on Strong Products \nCops and Robbers is a pursuit-evasion game played on the vertices of a graph. One player controls a set of cops and the other player controls a robber. The cops win if a cop can move to the vertex occupied by the robber in finitely many turns\, otherwise the robber wins. In this talk\, we consider a variation of Cops and Robbers where both players move simultaneously and the robber “cheats” by knowing how the cops will move each round. We will give bounds on the minimum number of cops needed to win this game when played on the strong product of two graphs. This is joint work with Nancy Clarke and Danny Dyer. \nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-4/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20231016 DTEND;VALUE=DATE:20231021 DTSTAMP:20260611T184459 CREATED:20230204T181746Z LAST-MODIFIED:20230204T181746Z UID:7080-1697414400-1697846399@aarms.math.ca SUMMARY:Women in Commutative Algebra II DESCRIPTION:The purpose of this event is to establish and enhance research networks among women and female identifying mathematicians who work in the areas of mathematics related to commutative algebra. It will be the second of its kind. The first one (Banff 2019) was an amazing success\, with many of the groups still working together. It has led to a strong network that besides research\, provides visibility for women and many opportunities for professional development. It has also served as an example for younger women. We are hoping that WICA II\, with its European location\, will be more accessible to a larger geographic area. \nWe need general funds\, as most of the sources we apply to are targetted to special regions. Any support from AARMS will be appreciated. If we do not raise enough funds\, the event will go ahead but we will have to reduce the number of participants. URL:https://aarms.math.ca/event/women-in-commutative-algebra-ii/ LOCATION:Trento\, Trento\, Italy CATEGORIES:AARMS sponsored events END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20231013 DTEND;VALUE=DATE:20231016 DTSTAMP:20260611T184459 CREATED:20230525T105834Z LAST-MODIFIED:20230525T105834Z UID:7220-1697155200-1697414399@aarms.math.ca SUMMARY:2023 Science Atlantic MSCS Conference DESCRIPTION:The Science Atlantic Mathematics\, Statistics\, and Computer Science Conference is an annual regional event. It provides a platform for undergraduate students in Mathematics\, Statistics and Computer Science at Atlantic Canadian universities to disseminate their research projects\, participate in contests\, and network with other students in the region. It also serves as a networking event for faculty members of Atlantic Canadian universities. In 2023\, University of Prince Edward Island will host the conference in Charlottetown\, PEI. The dates of the conference is October 13- 15\, 2023. Some of the major programs are as follows: Field Lecture\, Blundon Lecture\, Sedgewick Lecture\, Contributed Student’s talks\, Mathematics Competition\, CS Programming Competition\, AARMS Session\, Science Atlantic joint Math/CS meeting\, Science Atlantic Math and Stats. meeting\, Science Atlantic CS meeting\, Graduate Student’s Session etc. URL:https://aarms.math.ca/event/2023-science-atlantic-mscs-conference/ LOCATION:University of Prince Edward Island\, Charlottetown\, Prince Edward Island\, Canada CATEGORIES:AARMS sponsored events ORGANIZER;CN="Shafiqul Islam":MAILTO:sislam@upei.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20231004T153000 DTEND;TZID=UTC:20231004T163000 DTSTAMP:20260611T184459 CREATED:20230930T100717Z LAST-MODIFIED:20230930T100717Z UID:7351-1696433400-1696437000@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Speaker: Iain Beaton\, Acadia University\nTitle: On the Unimodality of Nearly-Well Dominated Trees\n\n\nAbstract: A polynomial is said to be unimodal if its coefficients are non-decreasing and then non-increasing. The domination polynomial of a graph G is the generating function of the number of dominating sets of each cardinality in G\, and its coefficients have been conjectured to be unimodal. In this talk we will show the domination polynomial of a tree T is unimodal so long as the sizes of the minimal dominating sets of T do not differ by too much. We will also discuss a version of this result for directed trees and its connection to the unimodality conjecture for the independence polynomial of a well-covered tree.\n\n \nZoom link:\n\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n\n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-3/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230920T153000 DTEND;TZID=UTC:20230920T163000 DTSTAMP:20260611T184459 CREATED:20230915T200900Z LAST-MODIFIED:20230915T200900Z UID:7306-1695223800-1695227400@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar DESCRIPTION:Time: 3.30pm\, Atlantic time\, Wednesday Sept.20\nSpeaker: Jessica McDonald\, Auburn University\n\nTitle: On flows (and group-connectivity) in signed graphs \nAbstract:\n\n\n\n\n\n\nIn this talk we’ll start by discussing flows in signed graphs and how it generalizes the usual notion of integer flows in graphs. In particular\, flow-colouring duality of graphs in the plane can be re-interpreted using signed graphs in the projective plane. Also\, where a flow in a graph can be viewed as a sum of flows on cycles\, in a signed graph\, positive cycles and barbells are the key structures to consider. We’ll share a new result\, joint with K. Nurse and A. Brewer-Castano\, about flows in 3-edge-connected signed graphs. In fact\, this result holds for the stronger notion of group-connectivity\, which was introduced as a generalization of flows by Jaeger\, Linial\, Payan\, and Tarsi in 1992. Building on their work and also on work by Li\, Luo\, Ma and Zhang (2018)\, we (mostly) establish a group-connected analog of Seymour’s 6-flow Theorem for signed graphs. \n\n\n\n\n\n\nZoom link:\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-2/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230821 DTEND;VALUE=DATE:20230828 DTSTAMP:20260611T184459 CREATED:20230131T104337Z LAST-MODIFIED:20230131T104337Z UID:7056-1692576000-1693180799@aarms.math.ca SUMMARY:Groups\, Rings\, Lie and Hopf Algebras. Fifth Edition DESCRIPTION:Our next International workshop “Groups\, Rings\, Lie and Hopf Algebras. V” will be held at the Harlow campus of Memorial University in the United Kingdom on August 21 – 27\, 2022. This is the first time the venue of our workshop will be outside North America. The web site of their campus is  here. \nThe organizing committee consists of Yuri Bahturin (Memorial University)\, Mikhail Kotchetov (Memorial University)\, Kirill Zaynullin (University of Ottawa)\, and Alexander Premet (University of Manchester). \nA preliminary list of speakers includes: \n\nAljadeff\, Eli (Technion)\nAra\, Pere (Universitat Autònoma de Barcelona)\nBaird\, Tom (Memorial University)\nBaranov\, Alexander (University of Leicester)\nBillig\, Yuly (Carleton University)\nBrzeziński\, Tomasz (Swansea University)\nElduque\, Alberto (Universidad de Zaragoza)\nJespers\, Eric (Vrije Universiteit Brussel)\nMartinez-Pedroza\, Eduardo  (Memorial University)\nMinasyan\, Ashot (University of Southampton)\nNeher\, Erhard (University of Ottawa)\nSchweigert\, Christoph (University of Hamburg)\nSierra\, Susan (University of Edinburgh)\nShpektorov\, Sergei (University of Birmingham)\nSmoktunowicz\, Agata (University of Edinburgh)\nSommerhäuser\, Yorck (Memorial University)\nTraustason\, Gunnar (University of Bath)\nVaughan-Lee\, Michael (University of Oxford)\nZalesski\, Alexandre (University of East Anglia)\n\nThe workshop is organized in the framework of the collaborative research group “Groups\, Rings\, Lie and Hopf Algebras” of the Atlantic Association for Research in the Mathematical Sciences (AARMS). An updated list of speakers and other information will be posted on this page. \nIf you are interested in attending the workshop\, please send an email to this address (aac@mun.ca) with GRLHA23 in the subject line by May 15\, 2023. If you would like to give a talk\, please include the title and abstract. \nThere are limited funds available to cover accommodation on the Harlow campus. If you would like to request this support\, please write to aac@mun.ca; if you are not a member of the collaborative research group\, please attach your CV. URL:https://aarms.math.ca/event/groups-rings-lie-and-hopf-algebras-fifth-edition/ LOCATION:Memorial University (Harlow Campus)\, 44 Market Street\, Harlow\, United Kingdom CATEGORIES:AARMS workshops and conferences ORGANIZER;CN="Mikhail Kotchetov":MAILTO:Mikhail@mun.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230731 DTEND;VALUE=DATE:20230802 DTSTAMP:20260611T184459 CREATED:20230801T124723Z LAST-MODIFIED:20230801T124723Z UID:7273-1690761600-1690934399@aarms.math.ca SUMMARY:2nd workshop of AARMS CRG on Mathematical Foundations of Scientific Machine Learning DESCRIPTION:This is the 2nd workshop of the AARMS Collaborative Research Group on Mathematical Foundations in Scientific Machine Learning\, which will be held on the Fredericton Campus of the University of New Brunswick on Jul 31 – Aug 01\, 2023. \nThe theme of the workshop is as broad as the scientific research programs of the partners in the AARMS CRG group\, including Machine Learning approaches in Mathematics\, Geophysics\, Chemistry\, Statistics\, etc. URL:https://aarms.math.ca/event/2nd-workshop-of-aarms-crg-on-mathematical-foundations-of-scientific-machine-learning/ LOCATION:University of New Brunswick (Fredericton Campus)\, Fredericton\, New Brunswick\, Canada CATEGORIES:AARMS workshops and conferences ORGANIZER;CN="Nicholas Touikan":MAILTO:nicholas.touikan@unb.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230731 DTEND;VALUE=DATE:20230805 DTSTAMP:20260611T184459 CREATED:20230204T180819Z LAST-MODIFIED:20230204T180819Z UID:7069-1690761600-1691193599@aarms.math.ca SUMMARY:6th International Conference on Applied Category Theory DESCRIPTION:Established in 2018\, the annual International Conference on Applied Category Theory brings together researchers\, programmers\, scientists and industry who seek to apply the foundational field of category theory to fields outside of mathematics. The ACT Adjoint School is annual research school adjoining the conference. The research school is aimed at fostering an open-hearted and open-minded environment where new applied category theorists develop the skills of research\, welcoming new researchers into cutting-edge research programs in applied category theory\, and to grow and strengthen the applied category theory community. The research school convenes online once every two weeks for 4 months before the conference and concludes research projects during the in-person research week before the conference. URL:https://aarms.math.ca/event/6th-international-conference-on-applied-category-theory/ LOCATION:University of Maryland\, college Park\, MD\, United States CATEGORIES:AARMS sponsored events ORGANIZER;CN="Priyaa Varshinee Srinivasan":MAILTO:priyaavarshinee.srin@ucalgary.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230730T130000 DTEND;TZID=UTC:20230730T173000 DTSTAMP:20260611T184459 CREATED:20230712T231641Z LAST-MODIFIED:20230717T144343Z UID:7247-1690722000-1690738200@aarms.math.ca SUMMARY:Bridges Math and Art Family Day DESCRIPTION:AARMS would like to invite everyone to the Bridges 2023 Math and Art family day!  This exciting event is part of the Bridges 2023 conference on Math and Art\, and will be held at the Halifax Central Library on Sunday\, July 30 from 1:00 pm to 5:30 pm.  Family day incorporates hands-on workshops\, mathematical poetry reading\, a short film festival\, and a mathematical art exhibition in the nearby Medjuck Building on Dalhousie’s Sexton Campus. URL:https://aarms.math.ca/event/bridges-math-and-art-family-day/ LOCATION:Halifax Central Library CATEGORIES:AARMS outreach events END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230727T200000 DTEND;TZID=UTC:20230727T213000 DTSTAMP:20260611T184459 CREATED:20230712T232857Z LAST-MODIFIED:20230712T235100Z UID:7251-1690488000-1690493400@aarms.math.ca SUMMARY:Public Lecture: The hat\, the turtle and the spectre DESCRIPTION:Come hear about the recent solution to a longstanding unsolved problem in geometry: it is possible for a single shape to tile the plane without any sort of repeating pattern? The “hat”\, it turns out\, solves this problem. It’s the first known aperiodic monotile\, also known as an “Einstein”. In this public lecture\, Craig Kaplan from the University of Waterloo (a member of the collaboration that discovered the “hat”)\, will talk about some background concepts from tiling theory and the history of the search for aperiodic shapes. The story of this discovery of the hat and the proof of its aperiodicity\, as well as two other closely related shapes\, the “turtle” and the “spectre”\, will dazzle you with their application to derive more results about aperiodic tilings. \nThis talk will be in the Irving Oil Auditorium in the Richard Murray Design Building on Thursday\, July 27 from 8:00 pm – 9:30 pm. \nRead more about the recent discovery of the aperiodic monotile: \n\nElusive ‘Einstein’ Solves a Longstanding Math Problem (New York Times)\nNewfound Mathematical ‘Einstein’ Shape Creates a Never-Repeating Pattern (Scientific American)\n‘The miracle that disrupts order’: mathematicians invent new ‘einstein’ shape (The Guardian)\nMathematicians say they have invented an ‘impossible’ tile that never repeats (CTV news) URL:https://aarms.math.ca/event/public-lecture-the-hat-the-turtle-and-the-spectre/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230727 DTEND;VALUE=DATE:20230801 DTSTAMP:20260611T184459 CREATED:20230712T231020Z LAST-MODIFIED:20230712T231020Z UID:7244-1690416000-1690847999@aarms.math.ca SUMMARY:Bridges Halifax 2023 DESCRIPTION:This conference is the premier international\, interdisciplinary conference connecting mathematics and art. The goal of the Bridges meetings is to foster research\, practice\, and new interest in mathematical connections to art\, music\, architecture\, education and culture. All too often\, mathematics can seem disconnected from or even antithetical to these other topics. We believe that mathematics and art can inform and enrich each other\, that there are great ideas waiting to be found in the mathematical analysis of art\, and that artistic thinking and activities can enliven what we understand about mathematics. \nThe Bridges conference brings together an interdisciplinary group of mathematicians\, scientists\, engineers\, artists\, educators\, musicians\, writers\, computer scientists\, sculptors\, dancers\, weavers\, model builders and many others in an atmosphere of mutual exchange and inspiration. \n  URL:https://aarms.math.ca/event/bridges-halifax-2023/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada CATEGORIES:AARMS workshops and conferences END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230711 DTEND;VALUE=DATE:20230715 DTSTAMP:20260611T184459 CREATED:20230204T180025Z LAST-MODIFIED:20230204T180025Z UID:7064-1689033600-1689379199@aarms.math.ca SUMMARY:29th Workshop on Logic\, Language\, Information and Computation DESCRIPTION:WoLLIC is an annual international forum on inter-disciplinary research involving formal logic\, computing and programming theory\, and natural language and reasoning. Each meeting includes invited talks and tutorials as well as contributed papers. The 29th WoLLIC will be held at Dalhousie University in Halifax\, Nova Scotia\, Canada\, July 11–14\, 2023. The conference typically covers the following topics: foundations of computing\, programming and Artificial Intelligence (AI); novel computation models and paradigms; broad notions of proof and belief; proof mining\, type theory\, effective learnability and explainable AI; formal methods in software and hardware development; logical approach to natural language and reasoning; logics of programs\, actions and resources; foundational aspects of information organization\, search\, flow\, sharing\, and protection; foundations of mathematics; philosophical logic; philosophy of language. URL:https://aarms.math.ca/event/29th-workshop-on-logic-language-information-and-computation/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada CATEGORIES:AARMS sponsored events ORGANIZER;CN="Peter Selinger":MAILTO:Peter.Selinger@Dal.Ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230710 DTEND;VALUE=DATE:20230715 DTSTAMP:20260611T184459 CREATED:20230204T182700Z LAST-MODIFIED:20230204T182700Z UID:7084-1688947200-1689379199@aarms.math.ca SUMMARY:Junior Math and Computer Science Camp DESCRIPTION:This week-long day camp is an opportunity for students entering grades 5 or 6 in the Annapolis Valley to participate in fun and enriching science-based activities with Acadia faculty and students to develop their curiosity and enjoyment of math and computer science. It represents an important piece of a multi-year plan to develop the science skills of young students in the Annapolis Valley by bringing young students into the Acadia University outreach program. This will begin the process of positively engaging students with math and computer science at a critical time in their education. Bursaries are provided for those who qualify for financial assistance. URL:https://aarms.math.ca/event/junior-math-and-computer-science-camp-3/ LOCATION:Acadia University\, Wolfville\, Nova Scotia\, Canada CATEGORIES:AARMS outreach events ORGANIZER;CN="Caroline Cochran":MAILTO:caroline.cochran@acadiau.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230616 DTEND;VALUE=DATE:20230619 DTSTAMP:20260611T184459 CREATED:20230204T180250Z LAST-MODIFIED:20230204T180250Z UID:7066-1686873600-1687132799@aarms.math.ca SUMMARY:Theory Canada 15 DESCRIPTION:Theory Canada is an annual meeting which brings together Canadian theorists from across the country in order to foster collaborations and exchange of ideas across the disciplines of theoretical physics. It is organized by the Division of Theoretical Physics of the Canadian Association of Physicists (CAP). Theory Canada 15 will be held at Mount Allison University from June 16-18\, 2023\, just before the main CAP meeting which will be in Fredericton. URL:https://aarms.math.ca/event/theory-canada-15/ LOCATION:Mount Allison University\, Sackville\, New Brunswick\, Canada CATEGORIES:AARMS sponsored events END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230605 DTEND;VALUE=DATE:20230609 DTSTAMP:20260611T184459 CREATED:20230204T181459Z LAST-MODIFIED:20230204T181459Z UID:7076-1685923200-1686268799@aarms.math.ca SUMMARY:Canadian Discrete and Algorithmic Mathematics conference DESCRIPTION:The Canadian Discrete and Algorithmic Mathematics (CanaDAM) is the pre-eminent conference in its area in Canada. It has been\nheld every two years since its founding in 2009. The general topic of the conference is the theory and application of\ndiscrete structures; the goal is to highlight the most salient trends in the field. CanaDAM will bring together researchers\nfrom the various disciplines with which discrete and algorithmic mathematics interact. Particular areas of interest include\ngraphs and digraphs\, hypergraphs\, matroids\, ordered sets\, designs\, coding theory\, enumeration\, combinatorics of words\,\ndiscrete optimization\, discrete and computational geometry\, lattice point enumeration\, combinatorial algorithms\,\ncomputational complexity\, and applications of discrete and algorithmic mathematics\, such as web graphs\, computational\nbiology\, telecommunication networks\, and information processing. CanaDAM strongly encourages participation from students and\npostdocs. We hope to see you there! URL:https://aarms.math.ca/event/canadian-discrete-and-algorithmic-mathematics-conference/ LOCATION:Winnipeg\, Manitoba\, Canada CATEGORIES:AARMS sponsored events ORGANIZER;CN="Mike Newman":MAILTO:mnewman@uottawa.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230510 DTEND;VALUE=DATE:20230512 DTSTAMP:20260611T184459 CREATED:20230204T181142Z LAST-MODIFIED:20230326T100317Z UID:7073-1683676800-1683849599@aarms.math.ca SUMMARY:East Coast Combinatorics Conference 2023 DESCRIPTION:The East Coast Combinatorics Conference is a 2-day annual event that brings together researchers in graph theory\, design theory\, and other areas of combinatorics. There will be two plenary speakers\, and a number of contributed talks\, in addition to opportunities for collaboration. The event brings together established researchers and those in the early stages of their academic careers and provides opportunities for subsequent collaborative research projects. We encourage participation by students since they greatly benefit from the opportunity to meet and interact with their peers across the region\, as well as to hear about the many and varied research interests of faculty. URL:https://aarms.math.ca/event/east-coast-combinatorics-conference-2023/ LOCATION:Acadia University\, Wolfville\, Nova Scotia\, Canada CATEGORIES:AARMS workshops and conferences ORGANIZER;CN="Nancy Clarke":MAILTO:nancy.clarke@acadiau.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230501 DTEND;VALUE=DATE:20230506 DTSTAMP:20260611T184459 CREATED:20230204T171542Z LAST-MODIFIED:20230206T104959Z UID:7060-1682899200-1683331199@aarms.math.ca SUMMARY:Topological Quantum Field Theory Spring School DESCRIPTION:Topological Quantum Field Theory lives at the intersection of category theory\, algebraic topology\, representation theory\, and theoretical physics. Physically\, TQFTs describe and control the symmetries of quantum systems\, including quantum symmetries\, anomalous symmetries\, and higher-form symmetries. Mathematically\, TQFTs provide a dictionary between manifold topology and structures in representation theory\, and as such allow computations and results to move between these separate fields. This school\, aimed at math PhD students from Atlantic Canada\, will consist of three 5-hour minicourses related to TQFTs\, plus problem sessions and discussion time; students are expected to be familiar with the basic language of category theory\, but are not expected to have any specialized knowledge in the field. The minicourses will be: Factorization Algebras (Araminta Amabel); Spectral Sequences (Arun Debray); Fusion Categories (Colleen Delaney). URL:https://aarms.math.ca/event/topological-quantum-field-theory-spring-school/ LOCATION:Old Orchard Inn and Conference Centre\, 153 Greenwich Road S.\, Wolfville\, Nova Scotia\, Canada CATEGORIES:AARMS sponsored events ORGANIZER;CN="Theo Johnson-Freyd":MAILTO:theojf@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Halifax:20230331T160000 DTEND;TZID=America/Halifax:20230331T170000 DTSTAMP:20260611T184459 CREATED:20200904T115630Z LAST-MODIFIED:20230224T143704Z UID:7130-1680278400-1680282000@aarms.math.ca SUMMARY:Dalhousie-AARMS AAMP Seminar: Erick Schulz (ETH Zürich) DESCRIPTION:Title + Abstract: TBD\nThe Dalhousie-AARMS Analysis-Applied Math-Physics Seminar takes place on Fridays from 4 – 5 pm Atlantic Time over either Zoom and/or in Chase 227 depending on the speaker.  If you would like to attend\, please email the organizers for connection details. URL:https://aarms.math.ca/event/dalhousie-aarms-aamp-seminar-steven-lester-kings-college-london-2-2-3-2-2-2-4-2-2-2-2-2-2-2-2-3/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada CATEGORIES:AAMP Seminar ORGANIZER;CN="Suresh Eswarathasan":MAILTO:sr766936@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230329T153000 DTEND;TZID=UTC:20230329T163000 DTSTAMP:20260611T184459 CREATED:20230325T113759Z LAST-MODIFIED:20230325T113833Z UID:7190-1680103800-1680107400@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar: Calum MacRury\, University of Toronto DESCRIPTION:Approximation Schemes for Resource Minimization for Fire Containment\nThe semi-random graph process is an example of an adaptive process for constructing a graph in which random edges are added step by step.  It is adaptive in that there is an online algorithm which has partial control over which random edges are added. Through intelligent decision-making\, the objective of the algorithm is to force the graph to satisfy a fixed graph property with high probability in as few rounds as possible. We first provide upper and lower bounds on the performance of an optimal algorithm when the property corresponds to being Hamiltonian or to containing a perfect matching. This part of the talk is based on joint works with Pawel Pralat and Jane Gao.Afterwards\, we introduce a formal definition of an adaptive random graph process which generalizes both the semi-random graph process\, as well as the Achlioptas process. In this model\, we define a condition called edge-replaceability  which we prove is sufficient for a property to have a sharp threshold. Intuitively\, a property has a sharp threshold if the optimal algorithm’s “success probability” transitions from almost $0$ to almost $1$ in a negligible number of steps.  We apply our result to the semi-random graph process to show that the properties of being Hamiltonian  and of containing a perfect matching each have a sharp threshold. This part of the talk is based on a joint work with Erlang Surya. URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-calum-macrury-university-of-toronto/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230322T153000 DTEND;TZID=UTC:20230322T163000 DTSTAMP:20260611T184459 CREATED:20230319T132045Z LAST-MODIFIED:20230319T132045Z UID:7186-1679499000-1679502600@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar: Mohammad Salavatipour\, U. Alberta DESCRIPTION:Approximation Schemes for Resource Minimization for Fire Containment\nResource Minimization Fire Containment (RMFC) is a natural model for optimal inhibition of\nharmful spreading phenomena on a graph. In the RMFC problem on trees\, we are given an undirected\ntree G\, and a vertex r where the fire starts at\, called root. At each time step\, the firefighters\ncan protect up to B vertices of the graph while the fire spreads from burning vertices to all their\nneighbors that have not been protected so far. The task is to find the smallest B that allows for\nsaving all the leaves of the tree. The problem is hard to approximate up to any factor better than 2\neven on trees unless P = NP. \nIn this talk we present an asymptotic QPTAS for RMFC on trees. More specifically\, let \eps > 0\,\nand F be an instance of RMFC where the optimum number of firefighters to save all the leaves is\nOPT(F). We present an algorithm which uses at most \ceil(1 + \eps )OPT(F)\rceil many firefighters at each\ntime step and runs in time n^O(\log\log n). This suggests that the existence of an asymptotic PTAS is\nplausible especially since the exponent is O(log log n). \n————————————————————-\nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09 \nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-mohammad-salavatipour-u-alberta/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Halifax:20230317T160000 DTEND;TZID=America/Halifax:20230317T170000 DTSTAMP:20260611T184459 CREATED:20200904T115630Z LAST-MODIFIED:20230314T085635Z UID:7000-1679068800-1679072400@aarms.math.ca SUMMARY:Dalhousie-AARMS AAMP Seminar: Milivoje Lukic (Rice U.) DESCRIPTION:Title: Universality limits for orthogonal polynomialsAbstract: It is often expected that the local statistical behavior ofeigenvalues of some system depends only on its local properties; forinstance\, the local distribution of zeros of orthogonal polynomials shoulddepend only on the local properties of the measure of orthogonality. Thisphenomenon is studied using an object called the Christoffel-Darbouxkernel. The most commonly studied case is known as bulk universality\,where the rescaled limit of Christoffel-Darboux kernels converges to thesine kernel.In this talk\, we will survey this subject\, prior results\, and a recentresult which gives for the first time a completely local sufficientcondition for bulk universality. The new approach is based on a matrixversion of the Christoffel-Darboux kernel and the de Branges theory ofcanonical systems\, and it applies to other self-adjoint systems with 2×2transfer matrices such as continuum Schrodinger and Dirac operators.The talk is based on joint work with Benjamin Eichinger (TechnicalUniversity Wien) and Brian Simanek (Baylor University).\nThe Dalhousie-AARMS Analysis-Applied Math-Physics Seminar takes place on Fridays from 4 – 5 pm Atlantic Time over either Zoom and/or in Chase 227 depending on the speaker.  If you would like to attend\, please email the organizers for connection details. URL:https://aarms.math.ca/event/dalhousie-aarms-aamp-seminar-steven-lester-kings-college-london-2-2-3-2-2-2-4-2-2-2-2-2-2-2-2/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada CATEGORIES:AAMP Seminar ORGANIZER;CN="Suresh Eswarathasan":MAILTO:sr766936@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230315T153000 DTEND;TZID=UTC:20230315T163000 DTSTAMP:20260611T184459 CREATED:20230315T123936Z LAST-MODIFIED:20230315T123936Z UID:7144-1678894200-1678897800@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar: Caleb Jones and Rylo Ashmore (Memorial University) DESCRIPTION:Speaker 1: Caleb Jones\, Memorial University\n \nTitle: Extending Graph Burning to Hypergraphs\n \nAbstract:\nWe introduce a round-based model much like graph burning which applies to hypergraphs. The rules for this new model are very natural\,and generalize the original model of graph burning. We also introduce a variant called lazy hypergraph burning\, along with a new parameter\, the lazy burning number. Interestingly\, lazily burning a graph is trivial\, while lazily burning a hypergraph can be quite complicated. Moreover\, the lazy burning model is a useful tool for analyzing the round-based model on hypergraphs. We obtain bounds on the burning number and lazy burning number of a hypergraph in terms of its parameters.\n \n \nSpeaker 2: Rylo Ashmore\, Memorial University\n \nTitle: Herding Cats Stuck in Trees.\n \nAbstract:\nIn the game of Cat Herding on a graph\, one player (the herder) will omnipresently delete edges\, while the other player (the cat) is on a vertex of the graph\, and will move along any path to a new vertex. Eventually\, the cat is isolated on a single vertex\, and the cat’s objective is to delay this event\, while the herder tries to hasten it. In an optimally played game\, the number of cuts the herder made to isolate the cat is the cat number of the graph. In this talk\, we will investigate this graph parameter for both dense and sparse graphs. We will see an argument that the asymptotic behaviour of the cat number of complete graphs is n^2/3. We also look at an unexpected connection between cat herding on trees and Fibonacci numbers. In particular\, we will see that trees with maximum cat number amongst graphs with n vertices have cat number asymptotically log_φ (n).\n\nZoom link: https://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09 \n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-caleb-jones-and-rylo-ashmore-memorial-university/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;VALUE=DATE:20230313 DTEND;VALUE=DATE:20230318 DTSTAMP:20260611T184459 CREATED:20230228T164404Z LAST-MODIFIED:20230228T164444Z UID:7135-1678665600-1679097599@aarms.math.ca SUMMARY:Automorphisms And Derivations In Affine Algebraic Geometry DESCRIPTION:Mini-course by Professor Leonid Makar-Limanov\, Wayne University\,  USA \nBrief description of the mini course\nAfter this course you will know the proofs of several classical theorems of Affine Algebraic Geometry. The original proofs of these theorems were quite involved and a much longer course would be needed for their exposition. \nIn the first lecture we will discuss the theorems of Heinrich Jung and Rudolf Rentschler. The first one describes all invertible transformations of the plane by polynomials and the second all generalized shifts of the plane. Algebraically speaking\, Jung’s theorem describes all automorphisms of the ring of polynomials with two variables and Rentschler theorem describes all subgroups of this group which are isomorphic to the group of complex numbers under addition. If we have time\, we will  discuss the groups of polynomial automorphisms of several other surfaces. \nThe second lecture is devoted to the following topic: if a cylinder is given\, is it possible to recover the base of this cylinder. In general the answer is no\, but we discuss two cases when this is possible. We show that if the cylinder over a curve is given then we can recover this curve (this is the theorem of Shreeram Abhyankar\, Paul Eakin\, and William Heinzer). If the cylinder over a surface is isomorphic to a three-dimensional space then the surface is isomorphic to a plane (this is a theorem of Takao Fujita). \nHere is an algebraic translation: \nIf A is an integral domain of transcendence degree one and A[x1\, x2\,…\, xn] is given\, we can recover A up to an isomorphism. If A is an integral domain of transcendence degree two and A[x] is isomorphic to C[y1\,y2\,y3] then A is isomorphic to C[z1\,z2].  The main tool used in these two lectures is locally nilpotent derivations. \nIn the third lecture we prove one of the most famous theorems in affine algebraic geometry\, the AMS Theorem (after Abhyankar\, Tsuong-tsieng Moh\, Masakazu Suzuki): any smooth “good” embedding of a line to a plane is the image of a coordinate line under an automorphism of the plane. Algebraically\, this means the following: if two polynomials f(t)\, g(t)∈ C[t] generate C[t] then the smaller of the degrees of f(t)\, g(t) divides the larger of the degrees of f(t)\, g(t). The main tool here is a new algorithm for finding an irreducible dependence between two polynomials in one variable. \nThe lectures will be delivered during three time periods\, as shown below. They will take place at the St. John’s campus of Memorial University and will be broadcast via Webex. All the times are in Newfoundland Time (NST=UTC-3:30). \nMonday\, March 13th: TBA \nTuesday\, March 14th: TBA \nThursday\, March 16th: TBA \nThe lectures will be available online via Webex.  The details will be given later.  Contact the organizers for more information:   Mikhail Kotchetov ;  Yuri A Bakhturin URL:https://aarms.math.ca/event/automorphisms-and-derivations-in-affine-algebraic-geometry/ LOCATION:Memorial University (St. John’s Campus)\, St. John's\, Newfoundland and Labrador\, Canada CATEGORIES:AARMS schools and minicourses ORGANIZER;CN="Mikhail Kotchetov":MAILTO:Mikhail@mun.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Halifax:20230310T160000 DTEND;TZID=America/Halifax:20230310T170000 DTSTAMP:20260611T184459 CREATED:20200904T115630Z LAST-MODIFIED:20221209T171625Z UID:6998-1678464000-1678467600@aarms.math.ca SUMMARY:Dalhousie-AARMS AAMP Seminar: Katrina Morgan (Northwestern University) DESCRIPTION:Title + Abstract: TBD\nThe Dalhousie-AARMS Analysis-Applied Math-Physics Seminar takes place on Fridays from 4 – 5 pm Atlantic Time over either Zoom and/or in Chase 227 depending on the speaker.  If you would like to attend\, please email the organizers for connection details. URL:https://aarms.math.ca/event/dalhousie-aarms-aamp-seminar-steven-lester-kings-college-london-2-2-3-2-2-2-4-2-2-2-2-2-2-2/ LOCATION:Dalhousie University\, Halifax\, Nova Scotia\, Canada CATEGORIES:AAMP Seminar ORGANIZER;CN="Suresh Eswarathasan":MAILTO:sr766936@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230308T153000 DTEND;TZID=UTC:20230308T163000 DTSTAMP:20260611T184459 CREATED:20230304T105511Z LAST-MODIFIED:20230304T105511Z UID:7138-1678289400-1678293000@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar: Lucas Mol\, Thomson Rivers University DESCRIPTION:Avoiding additive powers in words\nA word is a sequence of symbols taken from some finite alphabet. A square is a word of the form xx\, where x is a nonempty word. It is well-known that there are infinite words over an alphabet of size 3 that contain no squares. Suppose now that the alphabet is some finite subset of the integers. An additive square is a word of the form xx’\, where x and x’ have the same nonzero length and the same sum. Additive cubes\, fourth powers\, etc.\, are defined similarly. We present a method for proving that certain types of infinite words contain no additive k-powers. This is joint work with James Currie\, Narad Rampersad\, and Jeffrey Shallit.\n\n\n—————————————————————————————————————-\n\n\n\nJoin Zoom Meeting \nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-lucas-mol-thomson-rivers-university/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT BEGIN:VEVENT DTSTART;TZID=UTC:20230301T153000 DTEND;TZID=UTC:20230301T163000 DTSTAMP:20260611T184459 CREATED:20230226T121131Z LAST-MODIFIED:20230226T121131Z UID:7132-1677684600-1677688200@aarms.math.ca SUMMARY:Atlantic Graph Theory Seminar: Isaac McMullin and Ian George\, Dalhousie University DESCRIPTION:Speaker 1: Isaac McMullin \nExistence of Optimal Split Reliability Polynomials\nOne of the most common models of robustness of a graph against random failures has all vertices operational\, but the edges independently operational with probability p. On one hand\, one can ask for the probability that all vertices can communicate (all-terminal reliability) while on the other hand\, we can ask that two specific vertices (or terminals) can communicate with each other (two-terminal reliability). While both of these questions have been well-studied\, they are both increasing functions of the edge probability. One new approach is split reliability\, where for two fixed vertices s and t\, we consider the probability that every vertex communicates with one of s or t\, but not both. The split reliability of G is a polynomial function of p that for connected graphs is 0 both at p=0 and at p=1. In this presentation\, we explore the existence for fixed numbers n>=2 and m>=n-1 of an optimal connected (n\,m)-graph G_(n\,m) for split reliability\, that is\, a connected graph with n vertices and m edges for which for any other such graph H\, the split reliability of G_(n\,m) is at least as large as that of H\, for all values of p in [0\,1]. Unlike the similar problems for all-terminal and two-terminal reliability\, where only partial results are known\, we completely solve the issue for split reliability\, where we show that there is an optimal (n\,m)-graph for split reliability if and only if n<=3\, m=n-1\, or n=m=4. \n  \n\n\nSpeaker 2: Ian George \nDegree Polynomials of Graphs \nIn this talk we introduce the Degree Polynomial of a graph.  This polynomial is defined to be the generating function of the sequence (a_0\, a_1\, a_2\, …) where a_k is the number of vertices of degree k in a graph.  Little has been published about this polynomial other than its behaviour under graph operations.  We will explore some basic properties of this polynomial\, and see what information it encodes about a graph.  Then we will discuss the roots of degree polynomials\, or degree roots\, giving some bounds and density results.  Along the way\, the degree polynomials and degree roots for certain families of graphs will be highlighted. \n\nThe talks will be held in room 227 in the Chase building at Dalhousie\, and streamed via zoom \nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/86415230827?pwd=QUxLUnlMdWYzL05zSUJ4bnBCOUJnZz09\n\nMeeting ID: 864 1523 0827\nPasscode: 835547 URL:https://aarms.math.ca/event/atlantic-graph-theory-seminar-isaac-mcmullin-and-ian-george-dalhousie-university/ LOCATION:Online via Zoom CATEGORIES:AARMS Atlantic Graph Theory Seminar ORGANIZER;CN="jeannette Janssen":MAILTO:jeannette.janssen@dal.ca END:VEVENT END:VCALENDAR