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BEGIN:VEVENT
SUMMARY:Hermie Monterde (University of Manitoba)
DTSTART:20240916T211500Z
DTEND:20240916T221500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/1
DESCRIPTION:Title: Discrete mathematics in continuous quantum walks\
nby Hermie Monterde (University of Manitoba) as part of Number Theory and
Combinatorics Seminar (NTC)\n\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emily Quesada-Herrera (University of Lethbridge)
DTSTART:20241007T211500Z
DTEND:20241007T221500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/2
DESCRIPTION:Title: On the vertical distribution of the zeros of the Riem
ann zeta-function\nby Emily Quesada-Herrera (University of Lethbridge)
as part of Number Theory and Combinatorics Seminar (NTC)\n\nAbstract: TBA
\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alice Lacaze-Masmonteil (University of Regina)
DTSTART:20241021T211500Z
DTEND:20241021T221500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/3
DESCRIPTION:Title: Recent advances on the directed Oberwolfach problem\nby Alice Lacaze-Masmonteil (University of Regina) as part of Number Th
eory and Combinatorics Seminar (NTC)\n\n\nAbstract\nA directed variant of
the famous Oberwolfach problem\, the directed Oberwolfach problem consider
s the following scenario. Given $n$ people seated at $t$ round tables of s
ize $m_1\, m_2 \\ldots\, m_t$\, respectively\, such that $m_1+m_2+\\cdots+
m_t=n$\, does there exist a set of $n-1$ seating arrangements such that ea
ch person is seated to the right of every other person precisely once? I w
ill first demonstrate how this problem can be formulated as a type of grap
h-theoretic problem known as a cycle decomposition problem. Then\, I will
discuss a particular style of construction that was first introduced by R.
~Häggkvist in 1985 to solve several cases of the original Oberwolfach pro
blem. Lastly\, I will show how this approach can be adapted to the directe
d Oberwolfach problem\, thereby allowing us to obtain solutions for previo
usly open cases. Results discussed in this talk arose from collaborations
with Andrea Burgess\, Peter Danziger\, and Daniel Horsley.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fatma Cicek (University of Northern British Columbia)
DTSTART:20241104T221500Z
DTEND:20241104T231500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/4
DESCRIPTION:Title: Moments of Some Rankin-Selberg Convolution L-functio
ns Near The Central Point\nby Fatma Cicek (University of Northern Brit
ish Columbia) as part of Number Theory and Combinatorics Seminar (NTC)\n\n
\nAbstract\nIn this talk\, we will study the first and second twisted mome
nts of some Rankin-Selberg convolution L-functions of an automorphic form
of prime power level. Our first moment result can be used to prove that a
utomorphic forms of suitable weight and prime level are determined by the
central values of their Rankin-Selberg L-functions for convolutions with f
orms of prime power level. Our second moment result provides\, partially\,
a prime power level version of an earlier result of Kowalski\, Michel and
VanderKam for Rankin-Selberg convolutions of automorphic forms of prime l
evel. This is joint work with Alia Hamieh from the UNBC.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Golnoush Farzanfard (University of Lethbridge)
DTSTART:20241125T221500Z
DTEND:20241125T231500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/5
DESCRIPTION:Title: Zero Density for the Riemann zeta function\nby Go
lnoush Farzanfard (University of Lethbridge) as part of Number Theory and
Combinatorics Seminar (NTC)\n\n\nAbstract\nThe Riemann zeta function is a
fundamental function in number theory. The study of zeros of the zeta func
tion 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 integer
s. A less ambitious goal than proving there are no zeros is to deter- mine
an upper bound for the number of non-trivial zeros\, denoted as $N(\\sigm
a\, T)$\, within a specific rectangular region defined by $ \\sigma < Rs <
1$ and $0 < Im s < T$ . Previous works by various authors like Ingham 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 overview of th
e method they provide to deduce an upper bound for $N(\\sigma\, T)$. My th
esis will improve their upper bound and also update the result to use bett
er bounds on $\\zeta$ on the half line among other improvements.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Greg Knapp (University of Calgary)
DTSTART:20250120T191500Z
DTEND:20250120T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/6
DESCRIPTION:Title: On Certain Polytopes Associated to Products of Algebr
aic Integer Conjugates\nby Greg Knapp (University of Calgary) as 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 $\\vert\\alpha_0\\vert\\vert\\alpha_1\\vert^{c_1}\\cdo
ts\\vert\\alpha_k\\vert^{c_k}\\geq 1$ for any algebraic integer $\\alpha$
of degree $d$\, where we label its Galois conjugates as $\\alpha_0\,\\ldot
s\,\\alpha_{d-1}$ with\n$\\vert\\alpha_0\\vert\\geq \\vert\\alpha_1\\vert\
\geq\\cdots \\geq \\vert\\alpha_{d-1}\\vert$. First\, we give an explicit
description of $E_{k\,d}$ as a polytope with $2^k$ vertices. Then we prove
that for $d>3k$\, for every $(c_1\,\\ldots\,c_k)\\in E_{k\,d}$ and for ev
ery $\\alpha$ that is not a root of unity\, the strict inequality $\\vert\
\alpha_0\\vert\\vert\\alpha_1\\vert^{c_1}\\cdots\\vert\\alpha_k\\vert^{c_k
}>1$\nholds. We also provide a quantitative version of this inequality in
terms of $d$ and the height of the minimal polynomial of $\\alpha$.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lucas Villagra Torcomian (Simon Fraser University)
DTSTART:20250224T191500Z
DTEND:20250224T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/7
DESCRIPTION:Title: Perfect powers as sum of consecutive powers\nby L
ucas Villagra Torcomian (Simon Fraser University) as part of Number Theory
and Combinatorics Seminar (NTC)\n\n\nAbstract\nIn 1770 Euler observed tha
t $3^3 + 4^3 + 5^3 = 6^3$ and asked if there was another perfect power tha
t equals the sum of consecutive cubes. This captivated the attention of ma
ny important mathematicians\, such as Cunningham\, Catalan\, Genocchi 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 t
his equation. We will see some known results and one of the most used tool
s to attack this kind of problems. At the end we will show some new result
s that appear in arXiv:2404.03457.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paul Peringuey (University of British Columbia)
DTSTART:20250303T191500Z
DTEND:20250303T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/8
DESCRIPTION:Title: Refinements of Artin's primitive root conjecture\
nby Paul Peringuey (University of British Columbia) as part of Number Theo
ry 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 conjec
tured that the set of primes $p$ for which an\ninteger $a\\neq -1\,\\squar
e$ is a primitive root (i.e. $\\rm{ord}_p(a)=p-1$) has\na positive asympto
tic density among all primes. In 1967 Hooley proved this\nconjecture assum
ing the Generalized Riemann Hypothesis (GRH).\n\nIn this talk we will stud
y the behaviour of $\\rm{ord}_p(a)$ as $p$ varies over\nprimes\, in partic
ular we will show\, under GRH\, that the set of primes $p$ for\nwhich $\\r
m{ord}_p(a)$ is ``$k$ prime factors away'' from $p-1$ has a positive\nasym
ptotic density among all primes except for particular values of $a$ and\n$
k$. We will interpret being ``$k$ prime factors away'' in three different\
nways\, namely $k=\\omega(\\frac{p-1}{\\rm{ord}_p(a)})$\, $k=\\Omega(\\fra
c{p-1}\n{\\rm{ord}_p(a)})$ 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 exp
ectation for these\nquantities. \n\nFurthermore we will provide partial un
conditional answers to some of these\nquestions. This is joint work with L
eo Goldmakher and Greg Martin.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abbas Maarefparvar (University of Lethbridge)
DTSTART:20250127T191500Z
DTEND:20250127T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/9
DESCRIPTION:Title: Classification of some Galois fields with a fixed Pol
ya index\nby Abbas Maarefparvar (University of Lethbridge) as part of
Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nThe Polya gro
up $Po(K)$ of a Galois number field $K$ coincides with the subgroup of the
ideal class group $Cl(K)$ of $K$ consisting of all strongly ambiguous ide
al classes. We prove that there are only finitely many imaginary abelian
number fields $K$ whose `Polya index' $\\left[Cl(K):Po(K)\\right]$ is a fi
xed integer. Accordingly\, under GRH\, we completely classify all imaginar
y quadratic fields with the Polya indices 1 and 2. Also\, we unconditional
ly classify all imaginary biquadratic and imaginary tri-quadratic fields w
ith the Polya index 1. In another direction\, we classify all real quadrat
ic fields $K$ of extended R-D type (with possibly only one more field $K$)
for which $Po(K)=Cl(K)$. Our result generalizes Kazuhiro's classification
of all real quadratic fields of narrow R-D type whose narrow genus number
s are equal to their narrow class numbers. This is a joint work with Amir
Akbary (University of Lethbridge).\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emily Quesada Herrera (University of Lethbridge)
DTSTART:20250210T191500Z
DTEND:20250210T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/10
DESCRIPTION:Title: Fourier optimization and the least quadratic non-res
idue\nby Emily Quesada Herrera (University of Lethbridge) as part of N
umber Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nWe will explor
e how a Fourier optimization framework may be used to study two classical
problems in number theory involving Dirichlet characters: The problem of e
stimating the least character non-residue\; and the problem of estimating
the least prime in an arithmetic progression. In particular\, we show how
this Fourier framework leads to subtle\, but conceptually interesting\, im
provements on the best current asymptotic bounds under the Generalized Rie
mann Hypothesis\, given by Lamzouri\, Li\, and Soundararajan. Based on joi
nt work with Emanuel Carneiro\, Micah Milinovich\, and Antonio Ramos.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/10
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dave Morris (University of Lethbridge)
DTSTART:20250317T181500Z
DTEND:20250317T191500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/11
DESCRIPTION:Title: Colour-permuting automorphisms of complete Cayley gr
aphs\nby Dave Morris (University of Lethbridge) as part of Number Theo
ry and Combinatorics Seminar (NTC)\n\n\nAbstract\nA bijection f of a metri
c space is "distance-permuting" if the distance from f(x) to f(y) depends
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 composition of
an isometry and a dilation (x --> kx). So they are affine maps.\n\nWe stud
y the analogue in which G is any (finite or infinite) group\, and the "dis
tance" 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 property t
hat every distance-preserving bijection is an affine map. The smallest exc
eption is the quaternion group of order 8\, and all other exceptions are c
onstructed from this one.\n\nIt is natural to state the problem in the lan
guage of graph-theory: construct a graph by joining each pair of points (x
\,y) with an edge\, and label (or "colour") this edge with its length. The
n we are interested in bijections that permute the colours of the edges: 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 Alimirzaei.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/11
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrew Pearce-Crump (University of Bristol)
DTSTART:20250310T181500Z
DTEND:20250310T191500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/12
DESCRIPTION:Title: Number Theory versus Random Matrix Theory: the joint
moments story\nby Andrew Pearce-Crump (University of Bristol) as part
of Number Theory and Combinatorics Seminar (NTC)\n\n\nAbstract\nIt has be
en known since the 80s\, thanks to Conrey and Ghosh\, that the average of
the square of the Riemann zeta function\, summed over the extreme points o
f zeta up to a height T\, is $\\frac{1}{2} (e^2-5) \\log T$ as $T \\righta
rrow \\infty$. This problem and its generalisations are closely linked to
evaluating asymptotics of joint moments of the zeta function and its deriv
atives\, and for a time was one of the few cases in which Number Theory co
uld do what Random Matrix Theory could not. RMT then managed to retake the
lead in calculating these sorts of problems\, but we may now tell the sto
ry of how Number Theory is fighting back\, and in doing so\, describe how
to find a full asymptotic expansion for this problem\, the first of its ki
nd for any nontrivial joint moment of the Riemann zeta function. This is j
oint work with Chris Hughes and Solomon Lugmayer.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/12
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abbas Maarefparvar (University of Lethbridge)
DTSTART:20250924T193000Z
DTEND:20250924T203000Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/13
DESCRIPTION:Title: Short Proofs For Some Known Cohomological Results\nby Abbas Maarefparvar (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://researchseminars.org/talk/NumberTheoryandCombinatorics/13
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Caleb Marshall (University of British Columbia)
DTSTART:20251008T193000Z
DTEND:20251008T203000Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/14
DESCRIPTION:Title: Vanishing Sums of Roots of Unity: from Integer Tilin
gs to Projections of Fractal Sets\nby Caleb Marshall (University of Br
itish Columbia) as part of Number Theory and Combinatorics Seminar (NTC)\n
\nLecture held in MH 1060 (Markin Hall).\n\nAbstract\nA vanishing sum of r
oots of unity (VSRU) is a finite list $z_1\,...\,z_K$ of N-th complex root
s of unity whose sum is zero. While there are many simple examples---inclu
ding the famous "beautiful equation" of Euler\, $e^{i \\pi} + 1 = 0$---suc
h sums become extremely complex as the parameter N attains more complex pr
ime power divisors (and we will see several classical examples illustratin
g this idea\, as well as new examples from my work).\n\nOne fruitful line
of inquiry is to seek a quantitative relationship between the prime diviso
rs of N\, their associated exponents\, and the cardinality parameter K. A
theorem of T.Y. Lam and K.H. Leung from the early '90's states: K must alw
ays be (at least) as large as the smallest prime dividing N. This generali
zes the well known observation that that sum of all p-th roots of unity (w
here p is any prime number) must vanish\; and\, one notices that Euler's e
quation is one example of this fact.\n\nIn this talk\, we will discuss two
significant strengthenings of this result (one due to myself and I. Łaba
\, another due to myself\, G. Kiss\, I. Łaba and G. Somlai)\, which are d
erived from complexity measurements for polynomials with integer coefficie
nts which have many cyclotomic polynomial divisors. As applications\, we g
ive connections in two other areas of mathematics. The first is in the stu
dy of integer tilings: additive decompositions of the integers Z = A+B as
a sum set\, where each integer is represented uniquely. The second applica
tion is to the Favard length problem in fractal geometry\, which asks for
bounds upon the average length of the projections of certain dynamically-d
efined fractals onto lines.\n\nThis talk is based upon my individual 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 min
utes will include introductory ideas and examples for all results discusse
d in the latter portion of the talk.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/14
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Behruz Tayfeh-Rezaie (Institute for Research in Fundamental Scienc
es)
DTSTART:20251022T193000Z
DTEND:20251022T203000Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/15
DESCRIPTION:Title: Saturation in deterministic and random graphs\nb
y Behruz Tayfeh-Rezaie (Institute for Research in Fundamental Sciences) as
part of Number Theory and Combinatorics Seminar (NTC)\n\nLecture held 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 subgrap
h isomorphic to F but each graph obtained from G by joining a pair of nona
djacent vertices contains at least one copy of F as a subgraph. The satura
tion function of F\, denoted sat(n\, F)\, is the minimum number of edges i
n an F-saturated graph on n vertices. This parameter along with its counte
rpart\, 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 also prese
nt new results when F is a complete multipartite graph or a cycle graph. T
he problem of saturation in the Erdos-Renyi random graph G(n\, p) was intr
oduced by Korandi and Sudakov in 2017. We survey the results for random ca
se and present our latest results on saturation numbers of bipartite graph
s in random graphs\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/15
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Do Nhat Tan Vo (University of Lethbridge)
DTSTART:20251119T203000Z
DTEND:20251119T213000Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/16
DESCRIPTION:Title: Additive Sums of Shifted Ternary Divisor Function\nby Do Nhat Tan Vo (University of Lethbridge) as part of Number Theory a
nd Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (Markin Hall).\n
\nAbstract\nFix a positive integer $X$ and multi-sets of complex numbers $
\\mathcal{I}$ and $\\mathcal{J}$. We study the shifted convolution sum\n\\
[\nD_{\\mathcal{I}\,\\mathcal{J}}(X\,1) = \\sum_{n\\leq X} \\tau_{\\mathca
l{I}}(n)\\tau_{\\mathcal{J}}(n+1)\,\n\\]\nwhere $\\tau_{\\mathcal{I}}$ and
$\\tau_{\\mathcal{J}}$ are shifted divisor functions. These sums naturall
y appear in the study of higher moments of the Riemann zeta function and a
dditive problems in number theory. We review known results on $2k-$th mome
nt of the Riemann zeta function and correlation sums associated with gener
alized divisor function. Assuming a conjectural bound on the averaged leve
l of distribution of $\\tau_{\\mathcal{J}}(n)$ in arithmetic progressions\
, 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://researchseminars.org/talk/NumberTheoryandCombinatorics/16
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Antoine Leudière (University of Calgary)
DTSTART:20251126T203000Z
DTEND:20251126T213000Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/17
DESCRIPTION:Title: Point counting without points\nby Antoine Leudi
ère (University of Calgary) as part of Number Theory and Combinatorics Se
minar (NTC)\n\nLecture held in MH 1060 (Markin Hall).\n\nAbstract\nDrinfel
d modules are the analogues of elliptic curves in positive characteristic.
They are essential objects in number theory for studying function fields.
They do not have points\, in the traditional sense—we're going to count
them anyway! The first methods achieving this were inspired by classical
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://researchseminars.org/talk/NumberTheoryandCombinatorics/17
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicol Leong (University of Lethbridge)
DTSTART:20251203T203000Z
DTEND:20251203T213000Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/18
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Himanshu Gupta (University of Regina)
DTSTART:20260223T191500Z
DTEND:20260223T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/19
DESCRIPTION:Title: Minimum number of distinct eigenvalues of Johnson an
d Hamming graphs\nby Himanshu Gupta (University of Regina) as part of
Number Theory and Combinatorics Seminar (NTC)\n\nLecture held in MH 1060 (
Markin Hall).\n\nAbstract\nThis talk focuses on the inverse eigenvalue pro
blem for graphs (IEPG)\, which seeks to determine the possible spectra of
symmetric matrices associated with a given graph $G$. These matrices have
off-diagonal non-zero entries corresponding to the edges of $G$\, while di
agonal entries are unrestricted. A key parameter in IEPG is $q(G)$\, the m
inimum number of distinct eigenvalues among such matrices. The Johnson and
Hamming graphs are well-studied families of graphs with many interesting
combinatorial and algebraic properties. We prove that every Johnson graph
admits a signed adjacency matrix with exactly two distinct eigenvalues\, e
stablishing that its $q$-value is two. Additionally\, we explore the behav
ior of $q(G)$ for Hamming graphs. This is a joint work with Shaun Fallat\,
Allen Herman\, and Johnna Parenteau.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/19
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emanuela Marangone (University of Manitoba)
DTSTART:20260302T191500Z
DTEND:20260302T201500Z
DTSTAMP:20260422T212725Z
UID:NumberTheoryandCombinatorics/20
DESCRIPTION:Title: Cohomology on the incidence correspondence and the H
an-Monsky representation ring\nby Emanuela Marangone (University of Ma
nitoba) as part of Number Theory and Combinatorics Seminar (NTC)\n\nLectur
e held in MH 1060 (Markin Hall).\n\nAbstract\nThe study of the cohomology
of line bundles on (partial) flag varieties is an important problem at the
intersection of algebraic geometry\, commutative algebra\, and representa
tion theory. Over fields of characteristic zero\, this is well-understood
thanks to the Borel-Weil-Bott theorem\, but in positive characteristics\,
it remains largely open.\nIn this talk\, I will focus on the incidence cor
respondence\, the partial flag variety parameterizing pairs consisting of
a point in projective space and a hyperplane containing it. I will describ
e joint work with C. Raicu\, A. Kyomuhangi\, and E. Reed\, where we establ
ish a recursive formula for the characters of the cohomology of line bundl
es on the incidence correspondence in positive characteristic.\nFinally\,
I will highlight how this problem is unexpectedly connected to other open
questions in positive characteristic. In particular\, I will explain how o
ur work leads to a better understanding of the Han-Monsky representation r
ing\, the ring of isomorphism classes of finite-length graded k[T] modules
.\n
LOCATION:https://researchseminars.org/talk/NumberTheoryandCombinatorics/20
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cameron Franc (McMaster University)
DTSTART:20260316T181500Z
DTEND:20260316T191500Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/21
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Burgess (University of New Brunswick)
DTSTART:20260413T181500Z
DTEND:20260413T191500Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/22
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nathan Ng (University of Lethbridge)
DTSTART:20260309T181500Z
DTEND:20260309T191500Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/23
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Roberto Budzinski (Univeristy of Lethbridge)
DTSTART:20260323T181500Z
DTEND:20260323T191500Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/24
/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicol Leong (Univeristy of Lethbridge)
DTSTART:20260330T181500Z
DTEND:20260330T191500Z
DTSTAMP:20260422T212725Z
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://researchseminars.org/talk/NumberTheoryandCombinatorics/25
/
END:VEVENT
END:VCALENDAR