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Partition Identities and Quiver Representations Anna Weigandt - - PowerPoint PPT Presentation

Partition Identities and Quiver Representations Anna Weigandt University of Illinois at Urbana-Champaign weigndt2@illinois.edu November 20th, 2017 Based on joint work with Rich ard Rim anyi and Alexander Yong arXiv:1608.02030 Anna


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Partition Identities and Quiver Representations

Anna Weigandt

University of Illinois at Urbana-Champaign weigndt2@illinois.edu

November 20th, 2017 Based on joint work with Rich´ ard Rim´ anyi and Alexander Yong arXiv:1608.02030

Anna Weigandt Partition Identities and Quiver Representations

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Overview

This project provides an elementary explanation for a quantum dilogarithm identity due to M. Reineke. We use generating function techniques to establish a related identity, which is a generalization of the Euler-Gauss identity. This reduces to an equivalent form of Reineke’s identity in type A.

Anna Weigandt Partition Identities and Quiver Representations

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Representations of Quivers

Anna Weigandt Partition Identities and Quiver Representations

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Quivers

A quiver Q = (Q0, Q1) is a directed graph with vertices: i ∈ Q0 edges: a : i → j ∈ Q1

Anna Weigandt Partition Identities and Quiver Representations

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The Definition

A representation of Q is an assignment of a: vector space Vi to each vertex i ∈ Q0 and linear transformation fa : Vi → Vj to each arrow i

a

− → j ∈ Q1 dim(V ) = (dimVi)i∈Q0 is the dimension vector of V .

Anna Weigandt Partition Identities and Quiver Representations

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The Representation Space

Fix d ∈ NQ0. The representation space is RepQ(d) := ⊕

i

a

− →j∈Q1 Mat(d(i), d(j)). Let GLQ(d) := ∏

i∈Q0

GL(d(i)). GLQ(d) acts on RepQ(d) by base change at each vertex. Orbits of this action are in bijection with isomorphism classes of d dimensional representations.

Anna Weigandt Partition Identities and Quiver Representations

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Dynkin Quivers

A quiver is Dynkin if its underlying graph is of type ADE:

Anna Weigandt Partition Identities and Quiver Representations

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Gabriel’s Theorem

Theorem ([Gab75]) Dynkin quivers have finitely many isomorphism classes of indecomposable representations. For type A, indecomposables V[i,j] are indexed by intervals.

Anna Weigandt Partition Identities and Quiver Representations

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Lacing Diagrams

A lacing diagram ([ADF85]) L is a graph so that: the vertices are arranged in n columns labeled 1, 2, . . . , n the edges between adjacent columns form a partial matching.

Anna Weigandt Partition Identities and Quiver Representations

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Lacing Diagrams

A lacing diagram ([ADF85]) L is a graph so that: the vertices are arranged in n columns labeled 1, 2, . . . , n the edges between adjacent columns form a partial matching. Idea: Lacing diagrams are a way to visually encode representations

  • f an An quiver.

Anna Weigandt Partition Identities and Quiver Representations

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The Role of Lacing Diagrams in Representation Theory

When Q is a type A quiver, a lacing diagram can be interpreted as a sequence of partial permutation matrices which form a representation VL of Q. 1 2 3 4     [ 1 1 ] ,     1 1     ,   1       See [KMS06] for the equiorientated case and [BR04] for arbitrary orientations.

Anna Weigandt Partition Identities and Quiver Representations

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Equivalence Classes of Lacing Diagrams

Two lacing diagrams are equivalent if one can be obtained from the other by permuting vertices within a column.

Anna Weigandt Partition Identities and Quiver Representations

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Equivalence Classes of Lacing Diagrams

Two lacing diagrams are equivalent if one can be obtained from the other by permuting vertices within a column. {Equivalence Classes of Lacing Diagrams} ↕ {Isomorphism Classes of Representations of Q}

Anna Weigandt Partition Identities and Quiver Representations

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Strands

A strand is a connected component of L.

Anna Weigandt Partition Identities and Quiver Representations

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Strands

A strand is a connected component of L. m[i,j](L) = |{strands starting at column i and ending at column j}| Example: m[1,2](L) = 2

Anna Weigandt Partition Identities and Quiver Representations

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Strands

A strand is a connected component of L. m[i,j](L) = |{strands starting at column i and ending at column j}| Example: m[1,2](L) = 2

Anna Weigandt Partition Identities and Quiver Representations

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Strands

A strand is a connected component of L. m[i,j](L) = |{strands starting at column i and ending at column j}| Example: m[4,4](L) = 1

Anna Weigandt Partition Identities and Quiver Representations

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Strands

Strands record the decomposition of VL into indecomposable representations: VL ∼ = ⊕V

⊕m[i,j](L) [i,j]

Example: VL ∼ = V ⊕2

[1,2] ⊕ V[2,3] ⊕ V[2,4] ⊕ V[3,3] ⊕ V[4,4]

Anna Weigandt Partition Identities and Quiver Representations

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Reineke’s Identities

Anna Weigandt Partition Identities and Quiver Representations

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The Quantum Dilogarithm Series

E(z) =

k=0

qk2/2zk (1 − q)(1 − q2) . . . (1 − qk)

Anna Weigandt Partition Identities and Quiver Representations

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The Quantum Algebra of a Quiver

The Quantum Algebra AQ is an algebra over Q(q1/2) with generators: {yd : d ∈ NQ0} multiplication: yd1yd2 = q

1 2 (χ(d2,d1)−χ(d1,d2))yd1+d2

The Euler form χ : NQ0 × NQ0 → Z χ(d1, d2) = ∑

i∈Q0

d1(i)d2(i) − ∑

i

a

− →j∈Q1 d1(i)d2(j)

Anna Weigandt Partition Identities and Quiver Representations

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Reineke’s Identity

Given a representation V , we’ll write dV as a shorthand for ddim(V ). For a Dynkin quiver, it is possible to fix a choice of ordering on the simple representations: α1, . . . , αn indecomposable representations: β1, . . . , βN so that E(ydα1) · · · E(ydαn) = E(ydβ1) · · · E(ydβN ) (1) (Original proof given by [Rei10], see [Kel11] for exposition and a sketch of the proof.)

Anna Weigandt Partition Identities and Quiver Representations

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Reformulation

Looking at the coefficient of yd on each side, this is equivalent to the following infinite family of identities ([Rim13]):

n

i=1

1 (q)d(i) = ∑

η

qcodimC(η)

N

i=1

1 (q)mβi (η) . where the sum is over orbits η in RepQ(d) and mβ(η) is the multiplicity of β in V ∈ η. Here, (q)k = (1 − q) · · · (1 − qk) is the q-shifted factorial.

Anna Weigandt Partition Identities and Quiver Representations

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Some Bookkeeping

Fix a sequence of permutations w = (w(1), . . . , w(n)), so that w(i) ∈ Si and w(i)(i) = i. Let sj

i (L) = m[i,j−1](L)

and tk

i (L) = m[i,k](L) + m[i,k+1](L) + . . . + m[i,n](L).

Define the Durfee statistic: rw(L) = ∑

1≤i<j≤k≤n

sk

w(k)(i)(L)tk w(k)(j)(L).

Anna Weigandt Partition Identities and Quiver Representations

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Some Bookkeeping

Fix a sequence of permutations w = (w(1), . . . , w(n)), so that w(i) ∈ Si and w(i)(i) = i. Let sj

i (L) = m[i,j−1](L)

and tk

i (L) = m[i,k](L) + m[i,k+1](L) + . . . + m[i,n](L).

Define the Durfee statistic: rw(L) = ∑

1≤i<j≤k≤n

sk

w(k)(i)(L)tk w(k)(j)(L).

The above statistics are all constant on equivalence classes of lacing diagrams.

Anna Weigandt Partition Identities and Quiver Representations

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Theorem (Rim´ anyi, Weigandt, Yong, 2016) Fix a dimension vector d = (d(1), . . . , d(n)) and let w be as

  • before. Then

n

k=1

1 (q)d(k) = ∑

η∈L(d)

qrw(η)

n

k=1

1 (q)tk

k (η)

k−1

i=1

[tk

i (η) + sk i (η)

sk

i (η)

]

q

[j+k

k

]

q is the q-binomial coefficient and (q)k the q-shifted

factorial.

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series

Let S be a set equipped with a weight function wt : S → N so that |{s ∈ S : wt(s) = k}| < ∞ for each k ∈ N. The generating series for S is G(S, q) = ∑

s∈S

qwt(s).

Anna Weigandt Partition Identities and Quiver Representations

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Partitions

An integer partition is an ordered list of decreasing integers: λ = λ1 ≥ λ2 ≥ . . . ≥ λℓ(λ) > 0 We will typically represent a partition by its Young diagram: We weight a partition by counting the boxes in its Young diagram.

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

1 (q)∞ =

k=1

1 (1 − qk)

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

1 (q)∞ =

k=1

1 (1 − qk) =

k=1

(1 + qk + q2k + q3k + . . .)

Anna Weigandt Partition Identities and Quiver Representations

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Generating Series for Partitions

1 (q)∞ =

k=1

1 (1 − qk) =

k=1

(1 + qk + q2k + q3k + . . .) q16 = q1 · 1 · q3·3 · 1 · 1 · q6 · 1 · 1 · . . .

Anna Weigandt Partition Identities and Quiver Representations

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Notation

Let R(j, k) be the set consisting of a single rectangular partition of size j × k. G(R(j, k), q) =

Anna Weigandt Partition Identities and Quiver Representations

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Notation

Let R(j, k) be the set consisting of a single rectangular partition of size j × k. G(R(j, k), q) = qjk

Anna Weigandt Partition Identities and Quiver Representations

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Notation

Let R(j, k) be the set consisting of a single rectangular partition of size j × k. G(R(j, k), q) = qjk Let P(j, k) be the set of partitions constrained to a j × k

  • box. (Here, we allow j, k = ∞).

G(P(j, k), q) =

Anna Weigandt Partition Identities and Quiver Representations

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Notation

Let R(j, k) be the set consisting of a single rectangular partition of size j × k. G(R(j, k), q) = qjk Let P(j, k) be the set of partitions constrained to a j × k

  • box. (Here, we allow j, k = ∞).

G(P(j, k), q) = ??

Anna Weigandt Partition Identities and Quiver Representations

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P(∞, k): Partitions With at Most k Columns

Idea: Truncate the product

Anna Weigandt Partition Identities and Quiver Representations

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P(∞, k): Partitions With at Most k Columns

Idea: Truncate the product 1 (q)k =

k

i=1

1 (1 − qi)

Anna Weigandt Partition Identities and Quiver Representations

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P(k, ∞): Partitions With at Most k Rows

Idea: Bijection via conjugation

Anna Weigandt Partition Identities and Quiver Representations

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P(k, ∞): Partitions With at Most k Rows

Idea: Bijection via conjugation 1 (q)k =

k

i=1

1 (1 − qi)

Anna Weigandt Partition Identities and Quiver Representations

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q-Binomial Coefficients

q-Binomial Coefficient: If x and y are q commuting (yx = qxy), (x + y)n = ∑

i+j=n

[i + j i ]

q

xiyj.

Anna Weigandt Partition Identities and Quiver Representations

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Combinatorial Interpretation of the q-Binomial Coefficient

(x + y)11 = . . . + yyxyxyyxxyy + . . . x y y x y x y y x y y

Anna Weigandt Partition Identities and Quiver Representations

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Combinatorial Interpretation of the q-Binomial Coefficient

(x + y)11 = . . . + yyxyxyyxxyy + . . . x y y x y x y y x y y G(P(i, j), q) = [i + j i ]

q

Anna Weigandt Partition Identities and Quiver Representations

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Combinatorial Interpretation of the q-Binomial Coefficient

(x + y)11 = . . . + yyxyxyyxxyy + . . . x y y x y x y y x y y G(P(i, j), q) = [i + j i ]

q

= (q)i+j (q)i(q)j

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Squares and Rectangles

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Squares

The Durfee square D(λ) is the largest j × j square partition contained in λ.

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Squares

The Durfee square D(λ) is the largest j × j square partition contained in λ.

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Squares

P(∞, ∞) ← → ∪

j≥0

R(j, j) × P(j, ∞) × P(∞, j)

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Squares

P(∞, ∞) ← → ∪

j≥0

R(j, j) × P(j, ∞) × P(∞, j) Euler-Gauss identity: 1 (q)∞ =

j=0

qj2 (q)j(q)j (2) See [And98] for details and related identities.

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Rectangles

D(λ, −1) D(λ, 0) D(λ, 4) The Durfee Rectangle D(λ, r) is the largest s × (s + r) rectangular partition contained in λ.

Anna Weigandt Partition Identities and Quiver Representations

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Durfee Rectangles

D(λ, −1) D(λ, 0) D(λ, 4) The Durfee Rectangle D(λ, r) is the largest s × (s + r) rectangular partition contained in λ. 1 (q)∞ =

s=0

qs(s+r) (q)s(q)s+r . (3) ([GH68])

Anna Weigandt Partition Identities and Quiver Representations

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Proof of the Main Theorem

Anna Weigandt Partition Identities and Quiver Representations

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Theorem (Rim´ anyi, Weigandt, Yong, 2016) Fix a dimension vector d = (d(1), . . . , d(n)) and let w be as

  • before. Then

n

k=1

1 (q)d(k) = ∑

η∈L(d)

qrw(η)

n

k=1

1 (q)tk

k (η)

k−1

i=1

[tk

i (η) + sk i (η)

sk

i (η)

]

q

Anna Weigandt Partition Identities and Quiver Representations

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Theorem (Rim´ anyi, Weigandt, Yong, 2016) Fix a dimension vector d = (d(1), . . . , d(n)) and let w be as

  • before. Then

n

k=1

1 (q)d(k) = ∑

η∈L(d)

qrw(η)

n

k=1

1 (q)tk

k (η)

k−1

i=1

[tk

i (η) + sk i (η)

sk

i (η)

]

q

Idea: We will interpret each side as a generating series for tuples of

  • partitions. Giving a weight preserving bijection between these two

sets proves the identity.

Anna Weigandt Partition Identities and Quiver Representations

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The Left Hand Side

S = P(∞, d(1)) × . . . × P(∞, d(n))

Anna Weigandt Partition Identities and Quiver Representations

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The Left Hand Side

S = P(∞, d(1)) × . . . × P(∞, d(n)) G(S, q) =

n

i=1

G(P(∞, d(i)), q) =

n

i=1

1 (q)d(i)

Anna Weigandt Partition Identities and Quiver Representations

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The Right Hand Side

T = ∪

η∈L(d)

R(η) × P(η)

Anna Weigandt Partition Identities and Quiver Representations

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The Right Hand Side

T = ∪

η∈L(d)

R(η) × P(η) G(T, q) = ∑

η∈L(d)

G(R(η), q)G(P(η), q)

Anna Weigandt Partition Identities and Quiver Representations

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The map S → T

Let w = (1, 12, 123, 1234) and d = (8, 9, 11, 8). λ = (λ(1), λ(2), λ(3), λ(4)) ∈ S

Anna Weigandt Partition Identities and Quiver Representations

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λ → (µ, ν)

Anna Weigandt Partition Identities and Quiver Representations

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λ(1)

s2

1

t1

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(1)

t1

1

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(2)

t1

1

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(2)

t1

1

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 67

λ(2)

t1

1

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(2)

t2

1

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(2)

t2

1

t2

2

s2

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(3)

t2

1

t2

2

s3

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(3)

t2

1

t2

2

s3

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(3)

t2

1

t2

2

s3

1

Anna Weigandt Partition Identities and Quiver Representations

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λ(3)

t3

1

s3

1

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 74

λ(3)

t3

1

t3

2

t3

3

s3

1

s3

2

Anna Weigandt Partition Identities and Quiver Representations

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λ(4)

t3

1

t3

2

t3

3

Anna Weigandt Partition Identities and Quiver Representations

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λ(4)

t3

1

t3

2

t3

3

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 77

λ(4)

t3

1

t3

2

t3

3

Anna Weigandt Partition Identities and Quiver Representations

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λ(4)

t4

1

s4

1

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 79

λ(4)

t4

1

t4

2

t4

3

t4

4

s4

1

s4

2

s4

3

Anna Weigandt Partition Identities and Quiver Representations

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These Parameters are Well Defined

Lemma There exists a unique η ∈ L(d) so that sk

i (η) = sk i and tk j (η) = tk j

for all i, j, k.

Anna Weigandt Partition Identities and Quiver Representations

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A Recursion

For any η, sk

i (η) + tk i (η) = tk−1 i

(η) (4)

Anna Weigandt Partition Identities and Quiver Representations

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A Recursion

For any η, sk

i (η) + tk i (η) = tk−1 i

(η) (4) The parameters defined by Durfee rectangles satisfy the same equations:

t1

1

t2

1

t2

2

s2

1

t3

1

t3

2

t3

3

s3

1

s3

2

t4

1

t4

2

t4

3

t4

4

s4

1

s4

2

s4

3

λ → (µ, ν) ∈ T(η) ⊆ T

Anna Weigandt Partition Identities and Quiver Representations

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Connection with Reineke’s Identity (in type A)

Anna Weigandt Partition Identities and Quiver Representations

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Simplifying the Identity

Lets think about the blue terms: 1 (q)t1

1

[s2

1 + t2 1

s2

1

]

q

[s3

1 + t3 1

s3

1

]

q

[s4

1 + t4 1

s4

1

]

q

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 85

Simplifying the Identity

Lets think about the blue terms: 1 (q)t1

1

[s2

1 + t2 1

s2

1

]

q

[s3

1 + t3 1

s3

1

]

q

[s4

1 + t4 1

s4

1

]

q

= ( 1 (q)t1

1

) ( (q)s2

1+t2 1

(q)s2

1(q)t2 1

) ( (q)s3

1+t3 1

(q)s3

1(q)t3 1

) ( (q)s4

1+t4 1

(q)s4

1(q)t4 1

)

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 86

Simplifying the Identity

Lets think about the blue terms: 1 (q)t1

1

[s2

1 + t2 1

s2

1

]

q

[s3

1 + t3 1

s3

1

]

q

[s4

1 + t4 1

s4

1

]

q

= ( 1 (q)t1

1

) ( (q)s2

1+t2 1

(q)s2

1(q)t2 1

) ( (q)s3

1+t3 1

(q)s3

1(q)t3 1

) ( (q)s4

1+t4 1

(q)s4

1(q)t4 1

)

Anna Weigandt Partition Identities and Quiver Representations

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Simplifying the Identity

Lets think about the blue terms: 1 (q)t1

1

[s2

1 + t2 1

s2

1

]

q

[s3

1 + t3 1

s3

1

]

q

[s4

1 + t4 1

s4

1

]

q

= ( 1 (q)t1

1

) ( (q)s2

1+t2 1

(q)s2

1(q)t2 1

) ( (q)s3

1+t3 1

(q)s3

1(q)t3 1

) ( (q)s4

1+t4 1

(q)s4

1(q)t4 1

) = 1 (q)s2

1(q)s3 1(q)s4 1(q)t4 1 Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 88

Simplifying the Identity

Lets think about the blue terms: 1 (q)t1

1

[s2

1 + t2 1

s2

1

]

q

[s3

1 + t3 1

s3

1

]

q

[s4

1 + t4 1

s4

1

]

q

= ( 1 (q)t1

1

) ( (q)s2

1+t2 1

(q)s2

1(q)t2 1

) ( (q)s3

1+t3 1

(q)s3

1(q)t3 1

) ( (q)s4

1+t4 1

(q)s4

1(q)t4 1

) = 1 (q)s2

1(q)s3 1(q)s4 1(q)t4 1

= 1 (q)m[1,1](q)m[1,2](q)m[1,3](q)m[1,4]

Anna Weigandt Partition Identities and Quiver Representations

slide-89
SLIDE 89

Simplifying the Identity

Doing these cancellations yields the identity: Corollary (Rim´ anyi, Weigandt, Yong, 2016)

n

i=1

1 (q)d(i) = ∑

η∈L(d)

qrw(η) ∏

1≤i≤j≤n

1 (q)m[i,j](η) .

Anna Weigandt Partition Identities and Quiver Representations

slide-90
SLIDE 90

Simplifying the Identity

Doing these cancellations yields the identity: Corollary (Rim´ anyi, Weigandt, Yong, 2016)

n

i=1

1 (q)d(i) = ∑

η∈L(d)

qrw(η) ∏

1≤i≤j≤n

1 (q)m[i,j](η) . which looks very similar to:

n

i=1

1 (q)d(i) = ∑

η

qcodimC(η)

N

i=1

1 (q)mβi (η) .

Anna Weigandt Partition Identities and Quiver Representations

slide-91
SLIDE 91

A Special Sequence of Permutations

We associate permutations w(i)

Q ∈ Si to Q as follows:

Let w(1)

Q

= 1 and w(2)

Q

= 12. If ai−2 and ai−1 point in the same direction, append i to w(i−1)

Q

If ai−2 and ai−1 point in opposite directions, reverse w(i−1)

Q

and then append i wQ := (w(1)

Q , . . . , w(n) Q )

Anna Weigandt Partition Identities and Quiver Representations

slide-92
SLIDE 92

A Special Sequence of Permutations

We associate permutations w(i)

Q ∈ Si to Q as follows:

Let w(1)

Q

= 1 and w(2)

Q

= 12. If ai−2 and ai−1 point in the same direction, append i to w(i−1)

Q

If ai−2 and ai−1 point in opposite directions, reverse w(i−1)

Q

and then append i wQ := (w(1)

Q , . . . , w(n) Q )

Example: 1 2 3 4 5 6 a1 a2 a3 a4 a5 wQ = (1, 12, 123, 3214, 32145, 541236)

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 93

The Geometric Meaning of rw(η)

The Durfee statistic has the following geometric meaning: Theorem (Rim´ anyi, Weigandt, Yong, 2016) codimC(η) = rwQ(η) The above statement combined with the corollary implies Reineke’s quantum dilogarithm identity in type A.

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 94

References I

  • S. Abeasis and A. Del Fra.

Degenerations for the representations of a quiver of type Am. Journal of Algebra, 93(2):376–412, 1985.

  • G. E. Andrews.

The theory of partitions.

  • 2. Cambridge university press, 1998.
  • A. S. Buch and R. Rim´

anyi. A formula for non-equioriented quiver orbits of type a. arXiv preprint math/0412073, 2004.

  • M. Brion.

Representations of quivers. 2008.

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 95

References II

  • P. Gabriel.

Finite representation type is open. In Representations of algebras, pages 132–155. Springer, 1975.

  • B. Gordon and L. Houten.

Notes on plane partitions. ii. Journal of Combinatorial Theory, 4(1):81–99, 1968.

  • B. Keller.

On cluster theory and quantum dilogarithm identities. In Representations of algebras and related topics, EMS Ser.

  • Congr. Rep., pages 85–116. Eur. Math. Soc., Z¨

urich, 2011.

  • A. Knutson, E. Miller and M. Shimozono.

Four positive formulae for type A quiver polynomials. Inventiones mathematicae, 166(2):229–325, 2006.

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 96

References III

  • M. Reineke.

Poisson automorphisms and quiver moduli. Journal of the Institute of Mathematics of Jussieu, 9(03):653–667, 2010.

  • R. Rim´

anyi. On the cohomological Hall algebra of Dynkin quivers. arXiv:1303.3399, 2013.

Anna Weigandt Partition Identities and Quiver Representations

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SLIDE 97

Thank You!

Anna Weigandt Partition Identities and Quiver Representations