A matrix model for counting plane partitions and tilings Bertrand - - PowerPoint PPT Presentation

a matrix model for counting plane partitions and tilings
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A matrix model for counting plane partitions and tilings Bertrand - - PowerPoint PPT Presentation

A matrix model for counting plane partitions and tilings Bertrand Eynard, IPHT CEA-SACLAY STATCOMB, Dimer models and random tilings, oct. 2009 " ! B. Eynard, IPHT-CEA-SACLAY Matrix models and tilings Introduction B. Eynard,


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SLIDE 1

A matrix model for counting plane partitions and tilings

Bertrand Eynard, IPHT CEA-SACLAY STATCOMB, Dimer models and random tilings, oct. 2009

! " µ

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 2

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 3

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 4

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 5

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 6

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 7

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 8

Introduction

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 9

Introduction

tangent edge: Hermit cusp: Pearcey edge: Airy bulk: sine

In all those limits: statistics of cubes ∼ random matrix eigenvalues statistics.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 10

Introduction

tangent edge: Hermit cusp: Pearcey edge: Airy bulk: sine

Question: is there a matrix model whose eigenvalues statistics = statistics of cubes ? before any limit ?

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 11

Outline

Outline: Plane partitions, tilings and TASEP Rewriting as a matrix integral Tools available for matrix models Orthogonal polynomials, determinantal formulae, integrability, loop equations. topological expansion of the matrix model Large size asymptotics, liquid region. Examples Tiling the hexagon, the cardioid, TSSCPPs. Conclusion

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 12

Plane partitions

  • Plane partition, with 3 given boundaries λ, µ, ν:

Right ! N µ N " ! µ " Left N

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 13

Plane partitions

  • Plane partition, with 3 given boundaries λ, µ, ν:

Right ! N µ N " ! µ " Left N

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 14

Plane partitions

  • Plane partition, with 3 given boundaries λ, µ, ν:

! µ " Left N Right ! N µ N "

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 15

Plane partitions

  • Plane partition, with 3 given boundaries λ, µ, ν:

t ! ! "

= N self avoiding particles moving in a given region of the Rhombus lattice.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 16

Plane partitions

  • Plane partition, with 3 given boundaries λ, µ, ν:

h t h h h7 h h h3

4 5 6

h1

2

! µ "

= N self avoiding particles moving in a given region of the Rhombus lattice. hi(t), i = 1, . . . , N, hi(t) − t

2 ∈ Z,

hi(t + 1) = hi(t) ± 1

2,

h1(t) > h2(t) > h3(t) > · · · > hN(t) .

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 17

Generalization

N self avoiding particles moving in a given arbitrary domain D

  • f the Rhombus lattice.

hi(t), i = 1, . . . , N, hi(t) − t

2 ∈ Z,

h1(t) > h2(t) > h3(t) > · · · > hN(t), hi(t + 1) = hi(t) + 1

2 with proba α(t + 1 2)

hi(t + 1) = hi(t) − 1

2 with proba β(t + 1 2)

Possibility of having forbidden places, obliged places, non flat landscape, jumps other than ±1

2,...

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 18

Partition function

Right ! N µ N " ! µ " Left N

Plane partitions: ZNλ,Nµ,Nν(λ, µ, ν) =

  • π,∂π=(λ,µ,ν)

q|π| Example, Mac-Mahon formula Nλ = Nµ = Nν = ∞, λ, µ, ν = ∅: Z =

  • π

q|π| =

  • k=1

(1 − qk)−k = 1 + q + 3q2 + 6q3 + 13q4 + . . .

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 19

Partition function, TASEP

Generalization self-avoiding process in a domain D: Z =

  • h1(t)>···>hN(t)

tmax −1

  • t=tmin

N

  • i=1

e−Vt(hi(t)) qhi(t)

  • t′
  • i
  • α(t′) δhi(t′+ 1

2),hi(t′− 1 2)+ 1 2 + β(t′) δhi(t′+ 1 2),hi(t′− 1 2)− 1 2

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 20

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:
  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)
  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 21

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:
  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)
  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 22

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

δ(h(t + 1) − h(t) ± 1

2) =

i∞

−i∞ dr er(h(t+1)−h(t)) e± r/2.

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)
  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 23

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

α δ(h(t + 1) − h(t) + 1

2) + β δ(h(t + 1) − h(t) − 1 2) =

i∞

−i∞ dr er(h(t+1)−h(t)) (α er/2 + β e−r/2).

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)
  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 24

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

α δ(h(t + 1) − h(t) + 1

2) + β δ(h(t + 1) − h(t) − 1 2) =

i∞

−i∞ dr er(h(t+1)−h(t)) (α er/2 + β e−r/2).

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)

det(eri hj) = ∆(H)∆(R)

  • U(N) dU eTr R U H U†.
  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 25

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

α δ(h(t + 1) − h(t) + 1

2) + β δ(h(t + 1) − h(t) − 1 2) =

i∞

−i∞ dr er(h(t+1)−h(t)) (α er/2 + β e−r/2).

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)

det(eri(t+ 1

2)hj(t+1)) =

∆(H(t + 1))∆(R(t + 1

2))

  • U(N) dU eTr R(t+ 1

2) U H(t+1) U†,

det(e−ri(t+ 1

2)hj(t)) =

∆(H(t))∆(R(t + 1

2))

  • U(N) dU e− Tr R(t+ 1

2) U H(t) U†.

  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 26

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

α δ(h(t + 1) − h(t) + 1

2) + β δ(h(t + 1) − h(t) − 1 2) =

i∞

−i∞ dr er(h(t+1)−h(t)) (α er/2 + β e−r/2).

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)

det(eri(t+ 1

2)hj(t+1)) =

∆(H(t + 1))∆(R(t + 1

2))

  • U(N) dU eTr R(t+ 1

2) U H(t+1) U†,

det(e−ri(t+ 1

2)hj(t)) =

∆(H(t))∆(R(t + 1

2))

  • U(N) dU e− Tr R(t+ 1

2) U H(t) U†.

  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-27
SLIDE 27

Transformation into a matrix integral

Idea:

  • Gessel-Viennot:

h1(t)>···>hN(t)

  • i paths =

hi(t) det(paths).

  • Fourrier transform δ-functions:

α δ(h(t + 1) − h(t) + 1

2) + β δ(h(t + 1) − h(t) − 1 2) =

i∞

−i∞ dr er(h(t+1)−h(t)) (α er/2 + β e−r/2).

  • Harish Chandra-Itzykson-Zuber: H = diag(hi), R = diag(ri)

det(eri(t+ 1

2)hj(t+1)) =

∆(H(t + 1))∆(R(t + 1

2))

  • U(N) dU eTr R(t+ 1

2) U H(t+1) U†,

det(e−ri(t+ 1

2)hj(t)) =

∆(H(t))∆(R(t + 1

2))

  • U(N) dU e− Tr R(t+ 1

2) U H(t) U†.

  • Matrices: M(t) = U H(t) U† , ∆(H(t))2 dH(t) dU = dM(t),

and ˜ M(t′) = U† R(t′) U , ∆(R(t′))2 dR(t′) dU = d ˜ M(t′). hi(t) =eigenvalues of M(t), and ri(t) =eigenvalues of ˜ M(t′). → Matrix model

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 28

Matrix integral

We end up with Z = ∆(Htmax ) ∆(Htmin )

  • tmax −1
  • t=tmin

dM(t) e−Tr Vt(M(t)) qTr M(t)

  • tmax − 1

2

  • t′=tmin + 1

2

d ˜ M(t′) e−Tr ˜

Vt′( ˜ M(t′)) eTr ˜ M(t′) (M(t′+ 1

2)−M(t′− 1 2))

The potentials Vt(h) encode the domain, and landscape weight. The potentials ˜ Vt′ encode the jumps: e−˜

Vt′(x) = (α(t′)e− x

2 + β(t′)e x 2 ).

The eigenvalues of M(t) are hi(t) =position of the ith particle at time t.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 29

Summary matrix model

Theorem The "lozenge tiling/plane partitions/particle process" generating function Z, is a matrix integral. → Chain of matrices, with 2(tmax − tmin) + 1 matrices. Summary:

  • matrices M(t), t ∈ Z: eigenvalues hi(t) = particles,

potential e−Vt(h) characterizes the domain+landscape.

  • matrices ˜

M(t′), t′ ∈ Z + 1

2, eigenvalues ri(t′) = Lagrange

multipliers for jumps, potential e−˜

Vt′(r) = α(t′)e−r/2 + β(t′)er/2.

  • Angular parts= Fourier transform of Gessel-Viennot → HCIZ.
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 30

Generalities: Chain of matrices

Consider a general chain of matrices: Z =

  • dM1 . . . dMk e−Q Tr Pk

i=1 Vi(Mi)−ciMiMi+1

  • method of biorthogonal polynomials → determinantal
  • formuale. Correlation functions of eigenvalues are determinant
  • f some Christoffel-Darboux kernel [E., Mehta 1997].
  • Integrability → Z =tau-function, Hirota equation, various

pde’s.

  • method of loop equations → topological expansion

ln Z = ∞

g=0 Q2−2gFg.

  • Matrix laws universal limits = Bergman, Sine, Tracy-Widom

(= (1, 2)), Pearcey, Hermit, (p, q) conformal laws,...

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 31

Generalities: Loop equations

Consider a general chain of matrices Z =

  • dM1 . . . dMk e−Q Tr Pk

i=1 Vi(Mi)−ciMiMi+1

Assume it has a topological expansion: ln Z = ∞

g=0 Q2−2gFg.

Wn(x1, . . . , xn) =

  • Tr

1 x1 − M1 . . . Tr 1 xn − M1

  • c

=

  • g

Q2−2g−nW (g)

n

then, by solving loop equations (=integration by parts ⇒ equations relating correlation functions) we get: Theorem (E.-Prats Ferrer 2008) For every chain of matrices having a topological expansion, the W (g)

n

’s and Fg’s satisfy the "topological recursion".

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 32

Topological recursion

Define the recursion kernel: H(x0, x) = ¯

x x W (0) 2 (x0, x′) dx′

2(W (0)

1 (x) − W (0) 1 (¯

x)) Then the topological recursion [E.-Orantin 2007] is: W (g)

n+1(x0, J

  • x1, . . . , xn) =
  • i

Resx→aiH(x0, x)

  • W (g−1)

n+2

(x, x, J) +

g

  • h=0

  • I⊂J

W (h)

1+#I(x, I)W (g−h) 1+n−#I(x, J \ I)

  • → if one knows W (0)

1 (x) (called spectral curve S) and W (0) 2

(called Bergman kernel of S), then this recursion easily computes every W (g)

n

.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 33

Symplectic invariants

The Fg = W (g) ’s are computed (for g ≥ 2) by: Fg = W (g) = 1 2 − 2g

  • i

Resx→ai Φ(x) W (g)

1

dx where dΦ/dx = W (0)

1 (x).

+ more sophisticated expressions for F0 and F1, see [E. Orantin 2007]. Remark: Fg’s and W (g)

n

’s can be computed for any function W (0)

1 (x), related to any matrix model or not.

The Fg(S)’s and W (g)

n

’s are functionals of a spectral curve S = {W (0)

1 (x)}.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-34
SLIDE 34

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-35
SLIDE 35

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-36
SLIDE 36

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-37
SLIDE 37

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-38
SLIDE 38

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-39
SLIDE 39

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 40

Symplectic invariants

The Fg(S)’s are functionals of a spectral curve S = {W (0)

1 (x)}.

Examples:

  • W (0)

1 (x) = √x, then Wn = g W (g) n

= detn×n(Airy kernel).

  • W (0)

1 (x) = t x

√ x2 − a2, a2 = 2

3 (1 −

√ 1 − 12t), then Fg = enumerating quadrangulations of genus g.

  • W (0)

1 (x) = sin (√x ), then Fg = Vol(Mg)= Weil-Petersson.

  • y = W (0)

1 (x), solution of ex = ye−y, then W (g) n

=gen. function

  • f Hurwitz numbers of genus g.
  • y = W (0)

1 (x), solution of 0 = P(ex, ey) =mirror curve of some

toric CY 3-fold X, then Fg = Gromov − Witteng(X) (=[BKMP 2007] conjecture).

  • + plenty of other examples...
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 41

Symplectic invariants

Some general properties of the invariants Fg(S): (S = {y(x)})

  • homogeneity (g ≥ 2): Fg(λS) = λ2−2g Fg(S).
  • symplectic invariance Fg({y(x) + Ratl(x)}) = Fg({y(x)}),

Fg({−x(y)}) = Fg({y(x)}), Fg({λy(x/λ)}) = Fg({y(x)}).

  • Special geometry formulae for the derivatives

∂tFg =

  • t∗ W (g)

1

, where t∗ =dual cycle to the form ∂tydx.

  • Commute with limits:

lim Fg(S) ” = ” Fg(lim S).

  • Integrability: τ = e

P

g Fg Θ =Tau-function, satisfies Hirota.

Determinantal formulae: Wn =

g W (g) n

=determinants.

  • modular properties, ... etc
  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 42

Summary loop equations

Summary of the loop equation method:

  • If one knows the "spectral curve"

S = W (0)

1 (x) ” = ” lim 1 Q

  • tr
  • 1

x−M1

  • then: W (0)

2

=Bergman kernel of S (→ heat equation on S).

  • then: ln Z =

g Q2−2g Fg(S), where Fg(S) =symplectic

invariants of S.

  • and the W (g)

n

’s satisfy the topological recursion: Wn(x1, . . . , xn) =

  • Tr

1 x1 − M1 . . . Tr 1 xn − M1

  • c

=

  • g

Q2−2g−nW (g)

n

→ so, once W (0

1 (x) is known, corrections to all orders can be

easily computed.

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 43

Spectral curve for plane-partitions and TASEP

Result: Matrix model’s spectral curve W (0)

1 (x) ↔ limit shape of [Kenyon-Okounkov-Sheffield]

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 44

Examples

Hexagon’ spectral curve: t h T

aT N=bT

!T

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 45

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 0.001

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 46

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 0.1

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-47
SLIDE 47

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 0.3

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-48
SLIDE 48

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 0.8

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-49
SLIDE 49

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 10

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-50
SLIDE 50

Examples

Hexagon’ spectral curve: b = 2, a = 0.3, q = 1000

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-51
SLIDE 51

Example: TSSCPP’s

Totally Symmetric Self Complementary Plane Partitions

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-52
SLIDE 52

Example: TSSCPP’s

Totally Symmetric Self Complementary Plane Partitions

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-53
SLIDE 53

Example: TSSCPP’s

Totally Symmetric Self Complementary Plane Partitions

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-54
SLIDE 54

Example: TSSCPP’s

Totally Symmetric Self Complementary Plane Partitions

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-55
SLIDE 55

Example: TSSCPP’s

Example: N = 3 Z3(12) = 1 144

  • dM1dM2d ˜

M3/2d ˜ M5/2 e− tr (V1(M1)) q tr (M1+M2+M3) e− tr (˜

V3/2( ˜ M3/2)+˜ V5/2( ˜ M5/2)) e tr ( ˜ M3/2(M2−M1)+ ˜ M5/2(M3−M2))

tr (P2(M2)) M3 = diag(2, 3, 4) , P2(x) = 1 2(x − 3 2)(x − 7 2)(x − 9 2) e−V1(x) = (x − 2)(x − 5)

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

slide-56
SLIDE 56

Example: TSSCPP’s

Example: N = 3 → ASM ? Z3(12) = 1 144

  • dM1dM2d ˜

M3/2d ˜ M5/2 e− tr (V1(M1)) q tr (M1+M2+M3) e− tr (˜

V3/2( ˜ M3/2)+˜ V5/2( ˜ M5/2)) e tr ( ˜ M3/2(M2−M1)+ ˜ M5/2(M3−M2))

tr (P2(M2)) M3 = diag(2, 3, 4) , P2(x) = 1 2(x − 3 2)(x − 7 2)(x − 9 2) e−V1(x) = (x − 2)(x − 5)

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings

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SLIDE 57

Conclusion

  • General method: tiling problem → matrix model
  • saying that limit laws of plane partitions = matrix models limit

laws, is a truism.

  • possibility to use the huge matrix models toolbox:
  • rthogonal polynomials, integrability, loop equations, ...
  • loop equations → possibility to use the "topological recursion"

to find the asymptotic expansion (large size, or small ln q), to ALL ORDERS.

  • Possible application: Gromov-Witten invariants of toric CY

3-folds, [BKMP 2007] conjecture ("remodelling the B-model"): The Gromov-Witten invariants do satisfy the topological recursion ?

  • B. Eynard, IPHT-CEA-SACLAY

Matrix models and tilings