BEGIN:VCALENDAR
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BEGIN:VEVENT
SUMMARY:Hermie Monterde (University of Manitoba)
DTSTART:20240916T211500Z
DTEND:20240916T221500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/1
DESCRIPTION:Title: Discrete mathematics in continuous quantum wal
ks\nby Hermie Monterde (University of Manitoba) as part of Number Theo
ry and Combinatorics Seminar (NTC)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emily Quesada-Herrera (University of Lethbridge)
DTSTART:20241007T211500Z
DTEND:20241007T221500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/2
DESCRIPTION:Title: On the vertical distribution of the zeros of t
he Riemann zeta-function\nby Emily Quesada-Herrera (University of Leth
bridge) as part of Number Theory and Combinatorics Seminar (NTC)\n\nAbstra
ct: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alice Lacaze-Masmonteil (University of Regina)
DTSTART:20241021T211500Z
DTEND:20241021T221500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/3
DESCRIPTION:Title: Recent advances on the directed Oberwolfach pr
oblem\nby Alice Lacaze-Masmonteil (University of Regina) as part of Nu
mber Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nA directed vari
ant of the famous Oberwolfach problem\, the directed Oberwolfach problem c
onsiders the following scenario. Given $n$ people seated at $t$ round tabl
es of size $m_1\, m_2 \\ldots\, m_t$\, respectively\, such that $m_1+m_2+\
\cdots+m_t=n$\, does there exist a set of $n-1$ seating arrangements such
that each person is seated to the right of every other person precisely on
ce? I will first demonstrate how this problem can be formulated as a type
of graph-theoretic problem known as a cycle decomposition problem. Then\,
I will discuss a particular style of construction that was first introduce
d by R.~Häggkvist in 1985 to solve several cases of the original Oberwolf
ach problem. Lastly\, I will show how this approach can be adapted to the
directed Oberwolfach problem\, thereby allowing us to obtain solutions for
previously open cases. Results discussed in this talk arose from collabor
ations with Andrea Burgess\, Peter Danziger\, and Daniel Horsley.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fatma Cicek (University of Northern British Columbia)
DTSTART:20241104T221500Z
DTEND:20241104T231500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/4
DESCRIPTION:Title: Moments of Some Rankin-Selberg Convolution L-
functions Near The Central Point\nby Fatma Cicek (University of Northe
rn British Columbia) as part of Number Theory and Combinatorics Seminar (N
TC)\n\n\nAbstract\nIn this talk\, we will study the first and second twist
ed moments of some Rankin-Selberg convolution L-functions of an automorphi
c form of prime power level. Our first moment result can be used to prove
that automorphic forms of suitable weight and prime level are determined
by the central values of their Rankin-Selberg L-functions for convolutions
with forms of prime power level. Our second moment result provides\, part
ially\, a prime power level version of an earlier result of Kowalski\, Mic
hel and VanderKam for Rankin-Selberg convolutions of automorphic forms of
prime level. This is joint work with Alia Hamieh from the UNBC.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Golnoush Farzanfard (University of Lethbridge)
DTSTART:20241125T221500Z
DTEND:20241125T231500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/5
DESCRIPTION:Title: Zero Density for the Riemann zeta function
\nby Golnoush Farzanfard (University of Lethbridge) as part of Number Theo
ry and Combinatorics Seminar (NTC)\n\n\nAbstract\nThe Riemann zeta functio
n is a fundamental function in number theory. The study of zeros of the ze
ta function has important applications in studying the distribution of the
prime numbers. Riemann hypothesis conjectures that all non-trivial zeros
lie on the critical line\, while the trivial zeros occur at negative even
integers. A less ambitious goal than proving there are no zeros is to dete
r- mine an upper bound for the number of non-trivial zeros\, denoted as $N
(\\sigma\, T)$\, within a specific rectangular region defined by $ \\sigma
< Rs < 1$ and $0 < Im s < T$ . Previous works by various authors like Ing
ham and Ramare have provided bounds for $N(\\sigma\, T)$. In 2018\, Habiba
Kadiri\, Allysa Lumley\, and Nathan Ng presented a result that provides a
better estimate for $N(\\sigma\, T)$. In this talk I will give an overvie
w of the method they provide to deduce an upper bound for $N(\\sigma\, T)$
. My thesis will improve their upper bound and also update the result to u
se better bounds on $\\zeta$ on the half line among other improvements.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Greg Knapp (University of Calgary)
DTSTART:20250120T191500Z
DTEND:20250120T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/6
DESCRIPTION:Title: On Certain Polytopes Associated to Products of
Algebraic Integer Conjugates\nby Greg Knapp (University of Calgary) a
s part of Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nLet
$d>k$ be positive integers. Motivated by an earlier result of Bugeaud and
Nguyen\, we let $E_{k\,d}$ be the set of $(c_1\,\\ldots\,c_k)\\in\\mathbb
{R}_{\\geq 0}^k$ such that $\\vert\\alpha_0\\vert\\vert\\alpha_1\\vert^{c_
1}\\cdots\\vert\\alpha_k\\vert^{c_k}\\geq 1$ for any algebraic integer $\\
alpha$ of degree $d$\, where we label its Galois conjugates as $\\alpha_0\
,\\ldots\,\\alpha_{d-1}$ with\n$\\vert\\alpha_0\\vert\\geq \\vert\\alpha_1
\\vert\\geq\\cdots \\geq \\vert\\alpha_{d-1}\\vert$. First\, we give an ex
plicit description of $E_{k\,d}$ as a polytope with $2^k$ vertices. Then w
e prove that for $d>3k$\, for every $(c_1\,\\ldots\,c_k)\\in E_{k\,d}$ and
for every $\\alpha$ that is not a root of unity\, the strict inequality $
\\vert\\alpha_0\\vert\\vert\\alpha_1\\vert^{c_1}\\cdots\\vert\\alpha_k\\ve
rt^{c_k}>1$\nholds. We also provide a quantitative version of this inequal
ity in terms of $d$ and the height of the minimal polynomial of $\\alpha$.
\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lucas Villagra Torcomian (Simon Fraser University)
DTSTART:20250224T191500Z
DTEND:20250224T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/7
DESCRIPTION:Title: Perfect powers as sum of consecutive powers\nby Lucas Villagra Torcomian (Simon Fraser University) as part of Number
Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nIn 1770 Euler obser
ved that $3^3 + 4^3 + 5^3 = 6^3$ and asked if there was another perfect po
wer that equals the sum of consecutive cubes. This captivated the attentio
n of many important mathematicians\, such as Cunningham\, Catalan\, Genocc
hi and Lucas.\nIn the last decade\, the more general equation $x^k + (x+1)
^k + ⋯ + (x+d)^k = y^n$ began to be studied.\nIn this talk we will focus
on this equation. We will see some known results and one of the most used
tools to attack this kind of problems. At the end we will show some new r
esults that appear in arXiv:2404.03457.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paul Peringuey (University of British Columbia)
DTSTART:20250303T191500Z
DTEND:20250303T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/8
DESCRIPTION:Title: Refinements of Artin's primitive root conjectu
re\nby Paul Peringuey (University of British Columbia) as part of Numb
er Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nLet $\\rm{ord}_p(
a)$ be the order of $a$ in $(\\mathbb{Z}/p\\mathbb{Z})^*$. In 1927\, Artin
conjectured that the set of primes $p$ for which an\ninteger $a\\neq -1\,
\\square$ is a primitive root (i.e. $\\rm{ord}_p(a)=p-1$) has\na positive
asymptotic density among all primes. In 1967 Hooley proved this\nconjectur
e assuming the Generalized Riemann Hypothesis (GRH).\n\nIn this talk we wi
ll study the behaviour of $\\rm{ord}_p(a)$ as $p$ varies over\nprimes\, in
particular we will show\, under GRH\, that the set of primes $p$ for\nwhi
ch $\\rm{ord}_p(a)$ is ``$k$ prime factors away'' from $p-1$ has a positiv
e\nasymptotic density among all primes except for particular values of $a$
and\n$k$. We will interpret being ``$k$ prime factors away'' in three dif
ferent\nways\, namely $k=\\omega(\\frac{p-1}{\\rm{ord}_p(a)})$\, $k=\\Omeg
a(\\frac{p-1}\n{\\rm{ord}_p(a)})$ and $k=\\omega(p-1)-\\omega(\\rm{ord}_p(
a))$\, and present\nconditional results analogous to Hooley's in all three
cases and for all\ninteger $k$. From this\, we will derive conditionally
the expectation for these\nquantities. \n\nFurthermore we will provide par
tial unconditional answers to some of these\nquestions. This is joint work
with Leo Goldmakher and Greg Martin.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abbas Maarefparvar (University of Lethbridge)
DTSTART:20250127T191500Z
DTEND:20250127T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/9
DESCRIPTION:Title: Classification of some Galois fields with a fi
xed Polya index\nby Abbas Maarefparvar (University of Lethbridge) as p
art of Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nThe Po
lya group $Po(K)$ of a Galois number field $K$ coincides with the subgroup
of the ideal class group $Cl(K)$ of $K$ consisting of all strongly ambigu
ous ideal classes. We prove that there are only finitely many imaginary a
belian number fields $K$ whose `Polya index' $\\left[Cl(K):Po(K)\\right]$
is a fixed integer. Accordingly\, under GRH\, we completely classify all i
maginary quadratic fields with the Polya indices 1 and 2. Also\, we uncond
itionally classify all imaginary biquadratic and imaginary tri-quadratic f
ields with the Polya index 1. In another direction\, we classify all real
quadratic fields $K$ of extended R-D type (with possibly only one more fie
ld $K$) for which $Po(K)=Cl(K)$. Our result generalizes Kazuhiro's classif
ication of all real quadratic fields of narrow R-D type whose narrow genus
numbers are equal to their narrow class numbers. This is a joint work wit
h Amir Akbary (University of Lethbridge).\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emily Quesada Herrera (University of Lethbridge)
DTSTART:20250210T191500Z
DTEND:20250210T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/10
DESCRIPTION:Title: Fourier optimization and the least quadratic
non-residue\nby Emily Quesada Herrera (University of Lethbridge) as pa
rt of Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nWe will
explore how a Fourier optimization framework may be used to study two cla
ssical problems in number theory involving Dirichlet characters: The probl
em of estimating the least character non-residue\; and the problem of esti
mating the least prime in an arithmetic progression. In particular\, we sh
ow how this Fourier framework leads to subtle\, but conceptually interesti
ng\, improvements on the best current asymptotic bounds under the Generali
zed Riemann Hypothesis\, given by Lamzouri\, Li\, and Soundararajan. Based
on joint work with Emanuel Carneiro\, Micah Milinovich\, and Antonio Ramo
s.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dave Morris (University of Lethbridge)
DTSTART:20250317T181500Z
DTEND:20250317T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/11
DESCRIPTION:Title: Colour-permuting automorphisms of complete Ca
yley graphs\nby Dave Morris (University of Lethbridge) as part of Numb
er Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nA bijection f of
a metric space is "distance-permuting" if the distance from f(x) to f(y) d
epends only on the distance from x to y.\n\nFor example\, it is known that
every distance-permuting bijection of the Euclidean plane is the composit
ion of an isometry and a dilation (x --> kx). So they are affine maps.\n\n
We study the analogue in which G is any (finite or infinite) group\, and t
he "distance" from x to y is the "absolute value" of the unique element s
of G\, such that xs = y. We determine precisely which groups have the pro
perty that every distance-preserving bijection is an affine map. The small
est exception is the quaternion group of order 8\, and all other exception
s are constructed from this one.\n\nIt is natural to state the problem in
the language of graph-theory: construct a graph by joining each pair of po
ints (x\,y) with an edge\, and label (or "colour") this edge with its leng
th. Then we are interested in bijections that permute the colours of the e
dges: i.e.\, the colour of the edge from f(x) to f(y) depends only on the
colour of the edge from x to y.\n\nThis is joint work with Shirin Alimirza
ei.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrew Pearce-Crump (University of Bristol)
DTSTART:20250310T181500Z
DTEND:20250310T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/12
DESCRIPTION:Title: Number Theory versus Random Matrix Theory: th
e joint moments story\nby Andrew Pearce-Crump (University of Bristol)
as part of Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nIt
has been known since the 80s\, thanks to Conrey and Ghosh\, that the aver
age of the square of the Riemann zeta function\, summed over the extreme p
oints of zeta up to a height T\, is $\\frac{1}{2} (e^2-5) \\log T$ as $T \
\rightarrow \\infty$. This problem and its generalisations are closely lin
ked to evaluating asymptotics of joint moments of the zeta function and it
s derivatives\, and for a time was one of the few cases in which Number Th
eory could do what Random Matrix Theory could not. RMT then managed to ret
ake the lead in calculating these sorts of problems\, but we may now tell
the story of how Number Theory is fighting back\, and in doing so\, descri
be how to find a full asymptotic expansion for this problem\, the first of
its kind for any nontrivial joint moment of the Riemann zeta function. Th
is is joint work with Chris Hughes and Solomon Lugmayer.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abbas Maarefparvar (University of Lethbridge)
DTSTART:20250924T193000Z
DTEND:20250924T203000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/13
DESCRIPTION:Title: Short Proofs For Some Known Cohomological Res
ults\nby Abbas Maarefparvar (University of Lethbridge) as part of Numb
er Theory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Mark
in Hall).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Caleb Marshall (University of British Columbia)
DTSTART:20251008T193000Z
DTEND:20251008T203000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/14
DESCRIPTION:Title: Vanishing Sums of Roots of Unity: from Intege
r Tilings to Projections of Fractal Sets\nby Caleb Marshall (Universit
y of British Columbia) as part of Number Theory and Combinatorics Seminar
(NTC)\n\nLecture held in MH 1060 (Markin Hall).\n\nAbstract\nA vanishing s
um of roots of unity (VSRU) is a finite list $z_1\,...\,z_K$ of N-th compl
ex roots of unity whose sum is zero. While there are many simple examples-
--including the famous "beautiful equation" of Euler\, $e^{i \\pi} + 1 = 0
$---such sums become extremely complex as the parameter N attains more com
plex prime power divisors (and we will see several classical examples illu
strating this idea\, as well as new examples from my work).\n\nOne fruitfu
l line of inquiry is to seek a quantitative relationship between the prime
divisors of N\, their associated exponents\, and the cardinality paramete
r K. A theorem of T.Y. Lam and K.H. Leung from the early '90's states: K m
ust always be (at least) as large as the smallest prime dividing N. This g
eneralizes the well known observation that that sum of all p-th roots of u
nity (where p is any prime number) must vanish\; and\, one notices that Eu
ler's equation is one example of this fact.\n\nIn this talk\, we will disc
uss two significant strengthenings of this result (one due to myself and I
. Łaba\, another due to myself\, G. Kiss\, I. Łaba and G. Somlai)\, whic
h are derived from complexity measurements for polynomials with integer co
efficients which have many cyclotomic polynomial divisors. As applications
\, we give connections in two other areas of mathematics. The first is in
the study of integer tilings: additive decompositions of the integers Z =
A+B as a sum set\, where each integer is represented uniquely. The second
application is to the Favard length problem in fractal geometry\, which as
ks for bounds upon the average length of the projections of certain dynami
cally-defined fractals onto lines.\n\nThis talk is based upon my individua
l work\, as well as my joint work with I. Łaba\, as well as my joint work
with G. Kiss\, I. Łaba and G. Somlai. All are welcome\, and the first 15
-20 minutes will include introductory ideas and examples for all results d
iscussed in the latter portion of the talk.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Behruz Tayfeh-Rezaie (Institute for Research in Fundamental Scienc
es)
DTSTART:20251022T193000Z
DTEND:20251022T203000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/15
DESCRIPTION:Title: Saturation in deterministic and random graphs
\nby Behruz Tayfeh-Rezaie (Institute for Research in Fundamental Scien
ces) as part of Number Theory and Combinatorics Seminar (NTC)\n\nLecture h
eld in MH 1060 (Markin Hall).\n\nAbstract\nFix a positive integer n and a
graph F. A graph G with n vertices is called F-saturated if G contains no
subgraph isomorphic to F but each graph obtained from G by joining a pair
of nonadjacent vertices contains at least one copy of F as a subgraph. The
saturation function of F\, denoted sat(n\, F)\, is the minimum number of
edges in an F-saturated graph on n vertices. This parameter along with its
counterpart\, i.e. Turan number\, have been investigated for quite a long
time.\nWe review known results on sat(n\, F) for various graphs F. We als
o present new results when F is a complete multipartite graph or a cycle g
raph. The problem of saturation in the Erdos-Renyi random graph G(n\, p) w
as introduced by Korandi and Sudakov in 2017. We survey the results for ra
ndom case and present our latest results on saturation numbers of bipartit
e graphs in random graphs\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Do Nhat Tan Vo (University of Lethbridge)
DTSTART:20251119T203000Z
DTEND:20251119T213000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/16
DESCRIPTION:Title: Additive Sums of Shifted Ternary Divisor Func
tion\nby Do Nhat Tan Vo (University of Lethbridge) as part of Number T
heory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin H
all).\n\nAbstract\nFix a positive integer $X$ and multi-sets of complex nu
mbers $\\mathcal{I}$ and $\\mathcal{J}$. We study the shifted convolution
sum\n\\[\nD_{\\mathcal{I}\,\\mathcal{J}}(X\,1) = \\sum_{n\\leq X} \\tau_{\
\mathcal{I}}(n)\\tau_{\\mathcal{J}}(n+1)\,\n\\]\nwhere $\\tau_{\\mathcal{I
}}$ and $\\tau_{\\mathcal{J}}$ are shifted divisor functions. These sums n
aturally appear in the study of higher moments of the Riemann zeta functio
n and additive problems in number theory. We review known results on $2k-$
th moment of the Riemann zeta function and correlation sums associated wit
h generalized divisor function. Assuming a conjectural bound on the averag
ed level of distribution of $\\tau_{\\mathcal{J}}(n)$ in arithmetic progre
ssions\, we present an asymptotic formula for $D_{\\mathcal{I}\,\\mathcal{
J}}(X\,1)$ with explicit main terms and power-saving error estimates.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Antoine Leudière (University of Calgary)
DTSTART:20251126T203000Z
DTEND:20251126T213000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/17
DESCRIPTION:Title: Point counting without points\nby Antoine
Leudière (University of Calgary) as part of Number Theory and Combinator
ics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Hall).\n\nAbstract\nD
rinfeld modules are the analogues of elliptic curves in positive character
istic. They are essential objects in number theory for studying function f
ields. They do not have points\, in the traditional sense—we're going to
count them anyway! The first methods achieving this were inspired by clas
sical elliptic curve results\; we will instead explore an algorithm based
on so-called Anderson motives that achieves greater generality. Joint work
with Xavier Caruso.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicol Leong (University of Lethbridge)
DTSTART:20251203T203000Z
DTEND:20251203T213000Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/18
DESCRIPTION:by Nicol Leong (University of Lethbridge) as part of Number Th
eory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Ha
ll).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Himanshu Gupta (University of Regina)
DTSTART:20260223T191500Z
DTEND:20260223T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/19
DESCRIPTION:Title: Minimum number of distinct eigenvalues of Joh
nson and Hamming graphs\nby Himanshu Gupta (University of Regina) as p
art of Number Theory and Combinatorics Seminar (NTC)\n\nLecture held in MH
1060 (Markin Hall).\n\nAbstract\nThis talk focuses on the inverse eigenva
lue problem for graphs (IEPG)\, which seeks to determine the possible spec
tra of symmetric matrices associated with a given graph $G$. These matrice
s have off-diagonal non-zero entries corresponding to the edges of $G$\, w
hile diagonal entries are unrestricted. A key parameter in IEPG is $q(G)$\
, the minimum number of distinct eigenvalues among such matrices. The John
son and Hamming graphs are well-studied families of graphs with many inter
esting combinatorial and algebraic properties. We prove that every Johnson
graph admits a signed adjacency matrix with exactly two distinct eigenval
ues\, establishing that its $q$-value is two. Additionally\, we explore th
e behavior of $q(G)$ for Hamming graphs. This is a joint work with Shaun F
allat\, Allen Herman\, and Johnna Parenteau.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emanuela Marangone (University of Manitoba)
DTSTART:20260302T191500Z
DTEND:20260302T201500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/20
DESCRIPTION:Title: Cohomology on the incidence correspondence an
d the Han-Monsky representation ring\nby Emanuela Marangone (Universit
y of Manitoba) as part of Number Theory and Combinatorics Seminar (NTC)\n\
nLecture held in MH 1060 (Markin Hall).\n\nAbstract\nThe study of the coho
mology of line bundles on (partial) flag varieties is an important problem
at the intersection of algebraic geometry\, commutative algebra\, and rep
resentation theory. Over fields of characteristic zero\, this is well-unde
rstood thanks to the Borel-Weil-Bott theorem\, but in positive characteris
tics\, it remains largely open.\nIn this talk\, I will focus on the incide
nce correspondence\, the partial flag variety parameterizing pairs consist
ing of a point in projective space and a hyperplane containing it. I will
describe joint work with C. Raicu\, A. Kyomuhangi\, and E. Reed\, where we
establish a recursive formula for the characters of the cohomology of lin
e bundles on the incidence correspondence in positive characteristic.\nFin
ally\, I will highlight how this problem is unexpectedly connected to othe
r open questions in positive characteristic. In particular\, I will explai
n how our work leads to a better understanding of the Han-Monsky represent
ation ring\, the ring of isomorphism classes of finite-length graded k[T]
modules.\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cameron Franc (McMaster University)
DTSTART:20260316T181500Z
DTEND:20260316T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/21
DESCRIPTION:by Cameron Franc (McMaster University) as part of Number Theor
y and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Hall)
.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Burgess (University of New Brunswick)
DTSTART:20260413T181500Z
DTEND:20260413T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/22
DESCRIPTION:by Andrea Burgess (University of New Brunswick) as part of Num
ber Theory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Mar
kin Hall).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nathan Ng (University of Lethbridge)
DTSTART:20260309T181500Z
DTEND:20260309T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/23
DESCRIPTION:by Nathan Ng (University of Lethbridge) as part of Number Theo
ry and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Hall
).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Roberto Budzinski (Univeristy of Lethbridge)
DTSTART:20260323T181500Z
DTEND:20260323T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/24
DESCRIPTION:by Roberto Budzinski (Univeristy of Lethbridge) as part of Num
ber Theory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Mar
kin Hall).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicol Leong (Univeristy of Lethbridge)
DTSTART:20260330T181500Z
DTEND:20260330T191500Z
DTSTAMP:20260404T110830Z
UID:NumberTheoryandCombinatorics/25
DESCRIPTION:by Nicol Leong (Univeristy of Lethbridge) as part of Number Th
eory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Ha
ll).\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/NumberTheoryandCombinato
rics/25/
END:VEVENT
END:VCALENDAR