Lace expansions Critical Phenomena in Statistical Mechanics and - - PowerPoint PPT Presentation

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Lace expansions Critical Phenomena in Statistical Mechanics and - - PowerPoint PPT Presentation

Lace expansions Critical Phenomena in Statistical Mechanics and Quantum Field Theory PCTS, Princeton University David C. Brydges Prof. emeritus Mathematics Department University of British Columbia October 35, 2018 Abstract I will


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Lace expansions

Critical Phenomena in Statistical Mechanics and Quantum Field Theory PCTS, Princeton University

David C. Brydges

  • Prof. emeritus

Mathematics Department University of British Columbia October 3–5, 2018

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Abstract

I will explain the general principles of lace expansions, how they have been used, and some open problems related to their future.

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Plan for this lecture

The applications of the lace expansion are already beautifully reviewed – see for example (Slade, Notices of AMS Oct 2002). My only part in the process that made the lace expansion well known was to get Gordon Slade interested in it. He recruited Takashi Hara and many others; they proved the results you have heard about. But I have had experience with all kinds of expansions and today I want to talk about general themes, particularly resummations in terms of minimal graphs. Furthermore, lace expansions, unlike Mayer expansions, are convergent up to the physical critical point. What makes this possible? This lecture heads in this direction because I think there are other good resummations waiting for us to find them.

◮ Self-avoiding walk and a few results ◮ Ideas and background for the lace expansion ◮ Brief comments on percolation and spin models

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Self-avoiding walk (SAW)

Let ω = (ω0, . . . , ωn) be a sequence of nearest neighbours in Zd with ω0 = 0 and let Ωn be the set of all such ω with n fixed.

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Self-avoiding walk (SAW)

Let ω = (ω0, . . . , ωn) be a sequence of nearest neighbours in Zd with ω0 = 0 and let Ωn be the set of all such ω with n fixed. A SAW ω is a sequence of distinct nearest neighbours.

  • ω2

ω3 ω5 ω6 ω7 ω8 ω1 ω0 = 0 ω4

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Self-avoiding walk (SAW)

Let ω = (ω0, . . . , ωn) be a sequence of nearest neighbours in Zd with ω0 = 0 and let Ωn be the set of all such ω with n fixed. A SAW ω is a sequence of distinct nearest neighbours.

  • ω2

ω3 ω5 ω6 ω7 ω8 ω1 ω0 = 0 ω4

Give all SAW in Ωn equal probability.

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. ✶

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. Pn(ω) := cn

  • 1≤i<j≤n

(1 − λ✶ωi=ωj), ω ∈ Ωn.

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. Pn(ω) := cn

  • 1≤i<j≤n

(1 − λ✶ωi=ωj), ω ∈ Ωn. SAW = WSAW with λ = 1. Simple random walk is λ = 0.

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. Pn(ω) := cn

  • 1≤i<j≤n

(1 − λ✶ωi=ωj), ω ∈ Ωn. SAW = WSAW with λ = 1. Simple random walk is λ = 0. Two properties (D) and (S) these models might have:

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. Pn(ω) := cn

  • 1≤i<j≤n

(1 − λ✶ωi=ωj), ω ∈ Ωn. SAW = WSAW with λ = 1. Simple random walk is λ = 0. Two properties (D) and (S) these models might have: (D). As n → ∞, Eλ,n|ωn|2 ∼ cn for some c.

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Weakly self avoiding walk (WSAW)

Let λ ∈ [0, 1]. Pn(ω) := cn

  • 1≤i<j≤n

(1 − λ✶ωi=ωj), ω ∈ Ωn. SAW = WSAW with λ = 1. Simple random walk is λ = 0. Two properties (D) and (S) these models might have: (D). As n → ∞, Eλ,n|ωn|2 ∼ cn for some c. (S). As t → ∞, t−1/2ω[tn] converges in law to Brownian motion.

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Some results

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Some results

◮ (Brydges–Spencer 1985)

Let d ≥ 5. For λ sufficiently small (D) holds for WSAW.

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Some results

◮ (Brydges–Spencer 1985)

Let d ≥ 5. For λ sufficiently small (D) holds for WSAW.

◮ (G. Slade 1997, 1998)

For d sufficiently large (S) holds for SAW. Convergence of f.d. distributions from lace expansion, tightness from subadditivity.

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Some results

◮ (Brydges–Spencer 1985)

Let d ≥ 5. For λ sufficiently small (D) holds for WSAW.

◮ (G. Slade 1997, 1998)

For d sufficiently large (S) holds for SAW. Convergence of f.d. distributions from lace expansion, tightness from subadditivity.

◮ (Hara–Slade 1992)

(D) holds for SAW with d ≥ 5. For d = 4 E|ωn|2 ∼ cn log1/4 n is expected.

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Some results

◮ (Brydges–Spencer 1985)

Let d ≥ 5. For λ sufficiently small (D) holds for WSAW.

◮ (G. Slade 1997, 1998)

For d sufficiently large (S) holds for SAW. Convergence of f.d. distributions from lace expansion, tightness from subadditivity.

◮ (Hara–Slade 1992)

(D) holds for SAW with d ≥ 5. For d = 4 E|ωn|2 ∼ cn log1/4 n is expected.

◮ (Clisby–Liang–Slade 2007)

Enumeration via lace expansion; in 7 dimensions there are 504,552,243,465,714,026,682,387,806 SAW with n = 24 steps.

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Some results

◮ (Brydges–Spencer 1985)

Let d ≥ 5. For λ sufficiently small (D) holds for WSAW.

◮ (G. Slade 1997, 1998)

For d sufficiently large (S) holds for SAW. Convergence of f.d. distributions from lace expansion, tightness from subadditivity.

◮ (Hara–Slade 1992)

(D) holds for SAW with d ≥ 5. For d = 4 E|ωn|2 ∼ cn log1/4 n is expected.

◮ (Clisby–Liang–Slade 2007)

Enumeration via lace expansion; in 7 dimensions there are 504,552,243,465,714,026,682,387,806 SAW with n = 24 steps.

◮ (van der Hofstad 2001) ballistic behaviour for one-dimensional

WSAW.

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Comments

The last two illustrate surprising applications of the lace expansion. The first three set the pattern that recurs with different scalings in

  • ther applications. For example, one can replace walks by lattice

trees or lattice animals. In these cases the hypothesis is d ≥ 8 and the limiting process is integrated super-Brownian excursion.

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Comments

The last two illustrate surprising applications of the lace expansion. The first three set the pattern that recurs with different scalings in

  • ther applications. For example, one can replace walks by lattice

trees or lattice animals. In these cases the hypothesis is d ≥ 8 and the limiting process is integrated super-Brownian excursion. There are also results about lower dimensions, but one has to compensate by allowing the walk to have long range steps.

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Comments

The last two illustrate surprising applications of the lace expansion. The first three set the pattern that recurs with different scalings in

  • ther applications. For example, one can replace walks by lattice

trees or lattice animals. In these cases the hypothesis is d ≥ 8 and the limiting process is integrated super-Brownian excursion. There are also results about lower dimensions, but one has to compensate by allowing the walk to have long range steps. Now on to a discussion of the lace expansion itself,

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Relate SAW to simple random walk

Following Mayer in a different context, expand

  • 0≤i<j≤n

(1 − λ✶ωi=ωj) =

  • G⊂{all pairs}
  • ij∈G

(−λ✶ωi=ωj)

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Relate SAW to simple random walk

Following Mayer in a different context, expand

  • 0≤i<j≤n

(1 − λ✶ωi=ωj) =

  • G⊂{all pairs}
  • ij∈G

(−λ✶ωi=ωj) The right hand side has 2(n+1

2 ) terms of opposing signs!

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Relate SAW to simple random walk

Following Mayer in a different context, expand

  • 0≤i<j≤n

(1 − λ✶ωi=ωj) =

  • G⊂{all pairs}
  • ij∈G

(−λ✶ωi=ωj) The right hand side has 2(n+1

2 ) terms of opposing signs!

Let us see how a similar situation was handled by (O. Penrose 1967) in his work on convergence of the Mayer expansion.

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Excursion into the Mayer expansion

Particles at x1, . . . , xn in a finite set Λ. Grand canonical partition function Z =

  • n=0

zn n!

  • x∈Λn
  • 1≤i<j≤n

(1 − fij),.

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Excursion into the Mayer expansion

Particles at x1, . . . , xn in a finite set Λ. Grand canonical partition function Z =

  • n=0

zn n!

  • x∈Λn
  • 1≤i<j≤n

(1 − fij),.

= ✶{xi , xj incompatible}

By expanding the product Z becomes a sum over all graphs – connected and disconnected.

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Excursion into the Mayer expansion

Particles at x1, . . . , xn in a finite set Λ. Grand canonical partition function Z =

  • n=0

zn n!

  • x∈Λn
  • 1≤i<j≤n

(1 − fij),.

= ✶{xi , xj incompatible}

By expanding the product Z becomes a sum over all graphs – connected and disconnected. Mayer’s first theorem: log Z ∼

  • n=1

zn n!

  • G∈C(n)
  • x∈Λn
  • ij∈G

(−fij)

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Excursion into the Mayer expansion

Particles at x1, . . . , xn in a finite set Λ. Grand canonical partition function Z =

  • n=0

zn n!

  • x∈Λn
  • 1≤i<j≤n

(1 − fij),.

= ✶{xi , xj incompatible}

By expanding the product Z becomes a sum over all graphs – connected and disconnected. Mayer’s first theorem: log Z ∼

  • n=1

zn n!

  • G∈C(n)
  • x∈Λn
  • ij∈G

(−fij)

{connected graphs with vertices 1, . . . , n}

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Excursion into the Mayer expansion

Particles at x1, . . . , xn in a finite set Λ. Grand canonical partition function Z =

  • n=0

zn n!

  • x∈Λn
  • 1≤i<j≤n

(1 − fij),.

= ✶{xi , xj incompatible}

By expanding the product Z becomes a sum over all graphs – connected and disconnected. Mayer’s first theorem: log Z ∼

  • n=1

zn n!

  • G∈C(n)
  • x∈Λn
  • ij∈G

(−fij)

{connected graphs with vertices 1, . . . , n}

Penrose reduced the sum over C(n) to a sum over the set T (n) of tree graphs = minimally connected graphs.

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For each n choose an order on all possible edges

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For each n choose an order on all possible edges

Complete graph on n = 5 vertices

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For each n choose an order on all possible edges

Complete graph on n = 5 vertices

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For each n choose an order on all possible edges

Complete graph on n = 5 vertices 10 9 8 6 3 2 4 1 5 7

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For each n choose an order on all possible edges

Complete graph on n = 5 vertices 10 9 8 6 3 2 4 1 5 7 Orders edges for n = 5

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Define Kruskal map k : C(n) → T (n)

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop.

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7

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Define Kruskal map k : C(n) → T (n)

For G in C(n) pick edges in order discarding those that form a loop. 4 1 8 6 5 7 connected graph G is mapped to tree subgraph T

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The maximal graph M(T)

By construction, for any tree, k(T) = T.

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The maximal graph M(T)

By construction, for any tree, k(T) = T. Given a tree T, add all edges such that the resulting graph M is still mapped by k to T. One can add edges in any order to reach the same M.

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The maximal graph M(T)

By construction, for any tree, k(T) = T. Given a tree T, add all edges such that the resulting graph M is still mapped by k to T. One can add edges in any order to reach the same M. All graphs G such that k(G) = T satisfy T ⊂ G ⊂ M.

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The maximal graph M(T)

By construction, for any tree, k(T) = T. Given a tree T, add all edges such that the resulting graph M is still mapped by k to T. One can add edges in any order to reach the same M. All graphs G such that k(G) = T satisfy T ⊂ G ⊂ M. Thus M = M(T) is the maximal graph such that k(M) = T.

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The maximal graph M = M(T) such that k(M) = T

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The maximal graph M = M(T) such that k(M) = T

10 9 8 6 3 2 4 1 5 7

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The maximal graph M = M(T) such that k(M) = T

10 9 8 6 3 2 4 1 5 7 M is the red and dotted edges, i.e., all edges except the yellow edges.

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The maximal graph M = M(T) such that k(M) = T

10 9 8 6 3 2 4 1 5 7 M is the red and dotted edges, i.e., all edges except the yellow edges. No graph with yellow edge 3 < max{7, 4} can map to the red tree.

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The maximal graph M = M(T) such that k(M) = T

10 9 8 6 3 2 4 1 5 7 M is the red and dotted edges, i.e., all edges except the yellow edges. No graph with yellow edge 3 < max{7, 4} can map to the red tree. Likewise yellow edge 2 < max{5, 1, 7, 4}.

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The maximal graph M = M(T) such that k(M) = T

10 9 8 6 3 2 4 1 5 7 M is the red and dotted edges, i.e., all edges except the yellow edges. No graph with yellow edge 3 < max{7, 4} can map to the red tree. Likewise yellow edge 2 < max{5, 1, 7, 4}. The graphs that map to T are precisely graphs that contain T and any subset of the dotted lines.

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Penrose resummation formula

Lemma:

  • G∈C(n)

(−f )G =

  • T

(−f )T (1 − f )M(T)\T .

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Penrose resummation formula

Lemma:

  • G∈C(n)

(−f )G =

  • T

(−f )T (1 − f )M(T)\T .

=

  • ij∈G

(−fij )

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Penrose resummation formula

Lemma:

  • G∈C(n)

(−f )G =

  • T

(−f )T (1 − f )M(T)\T .

=

  • ij∈G

(−fij ) ∈ [0, 1] if fij ∈ [0, 1]

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Penrose resummation formula

Lemma:

  • G∈C(n)

(−f )G =

  • T

(−f )T (1 − f )M(T)\T .

=

  • ij∈G

(−fij ) ∈ [0, 1] if fij ∈ [0, 1]

This reduction from C(n) to T (n) easily implies that the expansion for log Z is absolutely convergent for z small.

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd new parameter z ≥ 0

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd new parameter z ≥ 0 set of simple walks with n steps and ωn = x

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd new parameter z ≥ 0 set of simple walks with n steps and ωn = x

χλ,z :=

  • x∈Zd

Gλ,z(x) is called the susceptibility.

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd new parameter z ≥ 0 set of simple walks with n steps and ωn = x

χλ,z :=

  • x∈Zd

Gλ,z(x) is called the susceptibility. Let zc = zc(λ) be the radius of convergence of χλ,z.

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Back to WSAW: define Greens function

Let Gλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • 1≤i<j≤n

(1 − λ✶ωi=ωj).

x ∈ Zd new parameter z ≥ 0 set of simple walks with n steps and ωn = x

χλ,z :=

  • x∈Zd

Gλ,z(x) is called the susceptibility. Let zc = zc(λ) be the radius of convergence of χλ,z. Objective: for d ≥ 5, λ small, Gλ,zc(λ)(x) ≤ 2G0,zc(0)(x)

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Comment

This is called an infrared bound. Once we get it from the lace expansion other results such as (D). As n → ∞, Eλ,n|ωn|2 ∼ cn for some c. are standard.

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Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

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Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

fij = λ✶{ωi =ωj }

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SLIDE 67

Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

fij = λ✶{ωi =ωj } {graphs on vertices 0, . . . , n }

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Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

fij = λ✶{ωi =ωj } {graphs on vertices 0, . . . , n }

1 n 2 6 f26

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Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

fij = λ✶{ωi =ωj } {graphs on vertices 0, . . . , n }

1 n 2 6 f26

Definition: Markovian vertices have no arches over them

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Graphical expansion for Gλ,z(x)

In the formula for Gλ,z(x) insert

  • 0≤i<j≤n

(1 − fij) =

  • G∈G[0,...,n]
  • ij∈G

(−fij)

fij = λ✶{ωi =ωj } {graphs on vertices 0, . . . , n }

1 n 2 6 f26

Definition: Markovian vertices have no arches over them

Say G ∈ C(n) if G has no Markovian points except 0.

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Define Πλ,z(x)

Πλ,z(x) :=

  • n=0

zn

  • ω∈Ωn(x)
  • G∈C(n)
  • ij∈G

(−λ✶ωi=ωj) which is an expansion in graphs without Markovian points whereas Gλ,z(x) =

  • n=0

zn

  • ω∈Ωn(x)
  • G∈G(n)
  • ij∈G

(−λ✶ωi=ωj) is an expansion in all possible graphs.

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Define k : C(n) → L(n)

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Define k : C(n) → L(n)

n

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Define k : C(n) → L(n)

n n

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Define k : C(n) → L(n)

n n n

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Define k : C(n) → L(n)

n n n n

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Define k : C(n) → L(n)

n n n n n

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Define k : C(n) → L(n)

n n n n n

Define L(n): L ∈ L(n) if L ∈ C(n) and is minimal. ✶

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Define k : C(n) → L(n)

n n n n n

Define L(n): L ∈ L(n) if L ∈ C(n) and is minimal. Lemma: This map k : C(n) → L(n) is such that ✶

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Define k : C(n) → L(n)

n n n n n

Define L(n): L ∈ L(n) if L ∈ C(n) and is minimal. Lemma: This map k : C(n) → L(n) is such that

  • G∈C(n)

(−f )G =

  • L∈L(n)

(−f )L (1 − f )M(T)\L, fij = λ✶ωi=ωj .

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Instead of (1 − f )M(T)\L ≤ 1 used in Mayer

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Instead of (1 − f )M(T)\L ≤ 1 used in Mayer

0 ≤ (1 − f )M(T)\L ≤

  • ij∈dotted edges

(1 − λ✶ωi=ωj)

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SLIDE 83

Instead of (1 − f )M(T)\L ≤ 1 used in Mayer

0 ≤ (1 − f )M(T)\L ≤

  • ij∈dotted edges

(1 − λ✶ωi=ωj) enabling a bootstrap. Gλ,z is expressed in terms of Πλ,z and Πλ,z is bounded in terms of G. A poor estimate on G can improve when passed through this circle.

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Π bounded by G

From the last Lemma and the definition of Π Πλ,z(x) =

  • n=0

zn

  • ω∈Ωn(x)
  • L∈L(n)

(−f )L (1 − f )M(T)\L,

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Π bounded by G

From the last Lemma and the definition of Π Πλ,z(x) =

  • n=0

zn

  • ω∈Ωn(x)
  • L∈L(n)

(−f )L (1 − f )M(T)\L, From the (1 − f )M(T)\L inequality, |Πλ,z(x)| ≤

+ + + + x

where in the Feynman diagrams on the RHS each line is Gλ,z(·) and each vertex has weight λ.

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Schwinger-Dyson replaces log ↔ connected graphs

For z ≤ zc, and if Πλ,z ∈ ℓ1, Gλ(z) = G0(z) + G0(z) ∗ Πλ(z) ∗ Gλ(z)

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SLIDE 87

Bootstrap

See Lace Expansion for Dummies, Bolthausen–van der Hofstad–Kozma 2017. If d ≥ 5, λ small and z < zc(λ) the estimate Gλ,z(x) ≤ 3G0,zc(0)(x) passed through the bootstrap Gλ,z → Gλ,z → Gλ,z implies the estimate Gλ,z(x) ≤ 2G0,zc(0)(x) (3 ⇒ 2) For z ≪ zc(λ), Gλ,z(x) ≤ 2G0,zc(0)(x) holds. continuity properties in z imply it holds z ≤ zc(λ).

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Percolation

Mean-Field Critical Behaviour for Percolation in High Dimensions: (Hara–Slade 1990). ✶ ✶

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Percolation

Mean-Field Critical Behaviour for Percolation in High Dimensions: (Hara–Slade 1990). Whenever we expand and resum

  • 1≤i<j≤n

(1 − ✶ωi=ωj) we are developing an inclusion-exclusion formula and the percolation lace expansion is an inclusion-exclusion formula modeled on the SAW

  • expansion. The BK inequality plays enough of the role of

1 − ✶ω(s)=ω(t) ≤ 1 that one can get the analogue of

+ + + + x

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SLIDE 90

Spin models

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SLIDE 91

Spin models

Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) ✶

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SLIDE 92

Spin models

Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) Application of the lace expansion to the ϕ4 model (A. Sakai 2015). ✶

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SLIDE 93

Spin models

Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) Application of the lace expansion to the ϕ4 model (A. Sakai 2015). In preparation: similar results as Akira Sakai, but also for the two component ϕ4 model. (Brydges-Helmuth-Holmes) Correlation inequalities play the role of 1 − ✶ω(s)=ω(t) ≤ 1

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SLIDE 94
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SLIDE 95

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003).

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SLIDE 96

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002)

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SLIDE 97

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004.

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SLIDE 98

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004. Random Subgraphs Of Finite Graphs: The Phase Transition For The n-Cube. (Borgs–J. Chayes–v. der Hofstad-Slade–J. Spencer 2006)

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SLIDE 99

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004. Random Subgraphs Of Finite Graphs: The Phase Transition For The n-Cube. (Borgs–J. Chayes–v. der Hofstad-Slade–J. Spencer 2006) Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007)

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SLIDE 100

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004. Random Subgraphs Of Finite Graphs: The Phase Transition For The n-Cube. (Borgs–J. Chayes–v. der Hofstad-Slade–J. Spencer 2006) Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) Lace expansion for the Ising model (high dimensions or finite range coupling). (A. Sakai 2007)

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SLIDE 101

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004. Random Subgraphs Of Finite Graphs: The Phase Transition For The n-Cube. (Borgs–J. Chayes–v. der Hofstad-Slade–J. Spencer 2006) Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) Lace expansion for the Ising model (high dimensions or finite range coupling). (A. Sakai 2007) Application of the lace expansion to the ϕ4 model (A. Sakai 2015).

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SLIDE 102

Convergence of critical oriented percolation to super-Brownian motion above 4+1 dimensions. (van der Hofstad–Slade 2003). Incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions (van der Hofstad–den Hollander–Slade 2002) Existence, properties of the incipient infinite cluster for high-dimensional unoriented percolation V der Hofstad–J´ arai 2004. Random Subgraphs Of Finite Graphs: The Phase Transition For The n-Cube. (Borgs–J. Chayes–v. der Hofstad-Slade–J. Spencer 2006) Lace expansion for the Ising model (high dimensions or finite range coupling). (A Sakai 2007) Lace expansion for the Ising model (high dimensions or finite range coupling). (A. Sakai 2007) Application of the lace expansion to the ϕ4 model (A. Sakai 2015). In preparation: similar results as Akira Sakai, but also for the two component ϕ4 model. (Brydges-Helmuth-Holmes)