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1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理(かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻 「物理学特別講義 BXI:非平衡統計力学の最近の展開」 2010年11月29日-12月1日,東京大学本郷キャンパス

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Page 1: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

1

Part 2 From Vicious Walk Model

to Random Matrix Theory

中央大学理工学部

香取眞理(かとりまこと)

集中講義:東京大学大学院理学系研究科物理学専攻「物理学特別講義

BXI:非平衡統計力学の最近の展開」

2010年11月29日-12月1日,東京大学本郷キャンパス

Page 2: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

2

• Let be the N-dimensional Markov chain starting from

x

= (x1 , x2 , …xN ), such that the coordinates S j (t) , j = 1,2,…,N, are independent

simple symmetric random walk on Z.

• Take the starting point x from the set

• With a constant T > 0

we impose the noncolliding

condition

up to time T ;

We denote by the conditional probability of under this noncolliding condition.

1. Vicious Walker Model

.,.....,2,1 ),(.....)()( 21 TttStStS N =<<<

)P)}(({ ,,...2,1,0xS =tt

{ }. ...:)2(),...,,( 2121 NN

NN xxxxxx <<<∈==< ZxZ

Michael Fisher calleda vicious walker model

in his Boltzmann

medal

lecture.

(M. E. Fisher, J. Statistical Physics 34

(1984) 667-729.)

( )xS Ttt Q ,)}({ ...3,2,1,0=

xx P QT

Page 3: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

3• We will assume that

• Each realization of vicious walk is represented by an N-tuple

of

nonintersecting lattice paths

on the 1+1 spatio-temporal plane, Z×{0,1,2,…,T}.

An example is given by Figure 1 on the case N=4 and T=6.

.1 ),1(2)0( NjjS j ≤≤−=

Page 4: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

4

•As a model of Wetting or Melting Transitions(Fisher (J. Statistical Physics 1984))

•As a model of Commensurate-Incommensurate Transitions(Huse

and Fisher (Physical Review B 1984))

Physical Motivations to Study Vicious Walker Models

Page 5: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

5

•As a model of Directed Polymer Networks(de Gennes

(J. Chemical Phys. 1968),

Essam

and Guttmann (Phys. Review E 1995))

(a) polymer with star topology

(b) polymer with watermelon topology

Page 6: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

62. Young Diagrams, Young Tableaux and Schur

Polynomials

A bijection

between vicious walks

and semistandard

Young tableaux (SSYT). [ Guttmann, Owczarek

and Viennot, J. Physics A (1998),

Krattenthaler, Guttmann and Viennot, J. Physics A (2000) ]

(1) Let

Lj = the number of leftward steps

among T steps of the j-th

walker, for j =1,2,…., N.

Draw a collection of boxes with

N columns,

in which the number of boxes in the j-th

column is Lj .

[

e.g., L = ( L1 , L2 , L3 , L4 )=( 3, 3, 2, 1 ) ](2)

For each walker, we label

each leftward step by the integer 1,2,…,T, which is the time when that leftward step is done.

(3)

Then for the j-th

column of the collections of boxes, fill the boxes

by the labels

of leftward steps

of the j-th

walker, from the top to the bottom,

j =1, 2,…, N.

Page 7: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

7Remark 1

L j = the number of leftward steps

among T steps of the j-th

walker, for j=1,2,…., N.

[

e.g., L=(L1 , L2 , L3 , L4 )=(3,3,2,1) ]

The noncolliding

condition

of vicious walkers

guarantees the equalities

Let

Then the equalities (2.1) imply

•The collections of boxes with conditions concerning the numbers of boxes in rows (2.2)(and in columns (2.1)) are called Young diagram (YD).

•The total number of rows in the YD is called the length l of YD.[ e.g., length l = 3. In general, length l =0,1,2,…, T ]

(2.1) . ....21 NLLL ≥≥≥

row.th - in the boxes ofnumber the kk =λ

(2.2) . ...21 lλλλ ≥≥≥

] )2,3,4(),,( [ 321 == λλλλe.g.,

Young diagram

Page 8: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

8Remark 2Let

T (j, k)=

the integer in the box located

in the

j-th

row and k-th

column,

The noncolliding

condition

of vicious walkers

guarantees the equalities

strictly

increasing

in each column,

weakly

increasing

in each row.

Young diagram with integers T=(T(j, k))satisfying the above ordering

of T(j, k)’s

are called Semi-Standard Young Tableaux (SSYT).

)1,( ),(

),1( ),(

+≤

+<

kjTkjT

kjTkjTYoung Tableau

Page 9: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

9• YD with boxes in the

k-th

row, k = 1,2, …, l , is

said to be the YD of shape

• Let L j = the number of boxes in the

j-th

column.

The YD with the shape L = (L1 , L2 , …

, LN ) is regarded as

the conjugate

of the YD with the shape

and denoted by

• As shown in Figure 3, they are mirror images with

respect to the diagonal line.

kλ. ),...,,( 21 lλλλ=λ

. ),...,,( 21 lλλλ=λ

. ~or ~ LλλL ==

• The sequence of integers in the weakly decreasing order(representing the number of boxes in rows of YD)

is regarded as a partition

of an integer

• The number of parts l is equal to or less than

T .We introduce a set of T variables

z =(z1 , z2 , …, zT ).

TkT λλλλλλλ ≥≥≥∈= ... , , ),...,,( 2121 Nλ

∑=

=T

kkn

Figure 3

Page 10: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

10

• For each SSYT, T=( T(j,k) ) , define a monomial

• e.g., for the SSYS shown in Figure 2 (b),

=

=

=

T

m

mm

kjkjT

z

z

1

Tin occurs integer that the timesof #

),(),(

Tz

365

3432

65

644

6432T

zzzzz

zzzzz

zzzz

=

×××××

×××=z

Page 11: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

11

Notice that for one YD

with a given shape , there are different ways of filling boxes with integers

to make SSYT.

For each YD

with shape , we define a polynomial

of z = (z1 , z2 , …, zT )

by summing the monomials over all SSYTdefined on that YD:

This polynomial is called the Schur

Function

indexed by (the partition/YD with shape)

λ

λ

. ),...,,( shape same with theSSYT all:T

T21 ∑=

λλ zTzzzs

• shape

of YD the final positions

of vicious walkers at t =

T.• variety of SSYT

on a YD variety of different vicious walks

with the same final positions

λ

Page 12: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

123. Enumeration of Vicious Walks with Fixed Final Positions

• There is a simple relation between

the number of leftward steps Lj , j =1, 2,…, N,

and the final positions yj , j = 1, 2,…, N, as

Lj = (T -

yj )/2 + ( j - 1), j = 1, 2,…, N,

or equivalently

yj = T - 2 Lj + 2 (j - 1), j = 1, 2,…, N.

bijections• final positions

y

of vicious walkers YD

with the shape

• one realization of vicious walk

one SSYT

T=( T (j, k) )from S(0)=(2(

j-1 )), j=1,..,N , to S(T) = y

with the shape

• set of all vicious walk

a Schur

functionfrom S(0)=(2( j-1 )), j=1,..,N , to

S

(T) = y

λ

λ

),...,,( 21 Tzzzsλ

)(conjugate ~ and Lλ Ly =⇔

Page 13: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

13

For L = (L1 , L2 , …, LN ) = ( (T -

yj )/2+(

j –

1) ) , set Then

. ),...,,()(1...21,

21 =====

TzzzTTN zzzsM λy

, ~Lλ =

DefinitionFor y1 < y2 < …

< yN , define the number

MN,T (y) = total number of distinct vicious walksof N walkers from the initial positions

Sj (0) = 2(j-1) ,

j=1,2,…, N to the final positions

Sj (T) = yj , j=1,2,…, N .

The above bijection

between vicious walks and Schur

functions gives the following identity.

Page 14: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

14Jacobi-Trudi

Formula ( )

( ) , det

det),...,,(

,1

,121 kT

jTkj

kTjTkj

T zz

zzzsk

−≤≤

−+≤≤=

λ

λ

( )( )

.

11 lim

detdet

lim

),...,,,1( lim)(

1

1

)1(

1

))(1(,1

))(1(,1

1

121,

1

≤<≤

≤<≤−

−+−−

−−≤≤

−+−≤≤

−→

−+−=

−−∑

=

=

=

=

Tkj

kj

Tkjjk

jkm

q

kTjTkj

kTjTkj

q

TqTN

jkjk

qqq

qq

qqqsM

kjT

mm

k

λλ

λλλ

λ

λy

Remark:

This is nothing but the dimension of the irreducible representation

R

with the highest weight of the unitary group U(T) λ

( ) ).(det tdeterminan eVandermond

1,1 ∏

≤<≤

−≤≤ −=

Tkjjk

kTjTkj zzz

Page 15: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

15

Jacobi-Trudi

formula. )],...,,([det),...,,( 21)(~,121 TkjNkjT zzzezzzs

k −+≤≤= λλ

By definition of elementary symmetric polynomials

t)coefficien (binomial )1,...,1,1( is, that

, )1( then , 1 all if ),...,,()1(0

2101

⎟⎟⎠

⎞⎜⎜⎝

⎛=

⎟⎟⎠

⎞⎜⎜⎝

⎛=+=⇒=+ ∑∑∏

===

kT

e

kT

zzzzez

k

kT

k

Tj

kT

T

kk

T

jj ξξξξ

. 2/))1(2(

det

det

~det )(

, )1(2/)( and ~ Since

,1

,1

,1,

⎥⎦

⎤⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−−+

=

⎥⎦

⎤⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−+

=

⎥⎦

⎤⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−+

=

−+−==

≤≤

≤≤

≤≤

kNkj

kNkj

kNkjTN

kk

yjTT

kjLT

kjT

M

jyTL

λy

Page 16: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

16

. 2/))1(2(

det )( ,1, ⎥⎦

⎤⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−−+

= ≤≤k

NkjTN yjTT

M y

Since

this expression of binomial-coefficient determinant

is regarded as a special case of

Karlin-McGregor formula

known in probability theory, and

Lindstrom-Gessel-Viennot

formula

known in combinatorics

theory.

, timefinal at the position theto 0 timeinitial at the )1(2position thefrom

plane temporal-spatio on the possible ofnumber the2/))1(2(

Ttytj

yjTT

k

k

==−

=⎟⎟⎠

⎞⎜⎜⎝

⎛−−+

paths single

Page 17: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

174. Enumeration of Vicious Walks with All Possible Final Positions

. 1

1

)(

10...: 1

...:,,

21

21

∏∑ ∏

≤<≤≥≥≥≥≥ ≤<≤

<<<

−+−++

=−

−+−=

=

TkjN Tkj

kj

yyyTNTN

kjkjN

jkjk

MM

T

N

λλλ

λλ

λ

yy

DefinitionMN,T = total number of distinct vicious walks

of N walkers from the initial positions Sj (0) = 2(j-1) ,

j=1,2,…, N

to any possible final positions at time T

Asymptotics

of the Survival Probability of Vicious Walkers

[Fisher (1984), Guttmann et al. (1998), Krattenthaler

(2000)]

).1(41 with

2,

, −=≈≡ − NNTM

P NNTTN

TNN ψψ

Page 18: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

18Summation Formula

. 1

110...: 121

∏∑ ∏≤<≤≥≥≥≥≥ ≤<≤ −+

−++=

−+−

TkjN Tkj

kj

kjkjN

jkjk

Tλλλ

λλ

λ

( )

( ) )conjecture sKnuth'-(Bender 1

1,...,,,1

)conjecture s(MacMahon'

1

11

1,...,,

,equalities twofollowing theofany oflimit 1by obtained is This

11

1

0...:

12

1 11

1

2/)12(

2/)12(

0...:

2/12/)32(2/)12(

21

21

∏∑

∏ ∏∑

≤<≤−+

−++

≥≥≥≥≥

= ≤<≤−+

−++

−+

≥≥≥≥≥

−−

−−

=

−−

−−

=

Tkjkj

kjN

N

T

T

i Tkjkj

kjN

i

iN

N

TT

qqqqqs

qq

qqqqqs

q

T

T

λλλ

λλλ

λλ

λλ

Page 19: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

19

More general summation formula is given in the textbook of Macdonald

. )(det)(det

),...,,( 21,1

21,1

0...:21

21

jTi

jiTji

jTNi

jiTji

TN zz

zzzzzs

T

−−≤≤

−+−≤≤

≥≥≥≥≥ −

−=∑

λλλλλ

Remark{ }

{ }T

T

NTN

TN

N

∈×

⎭⎬⎫

⎩⎨⎧

≤≤

≥≥≥≥≥

λ

λ

λ

:rectangle an in included YD

)( parts ofnumber with theand rowfirst theoflength with theYD

0....:

1

21

c

l

c

λ

λλλ

Page 20: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

205. Diffusion Scaling Limit

{ }

. )|,(f y),(Ν

by given is 0 t time toup of

boundary hit thenot does at startedmotion Brownian y that theprobabilit The

. in motion Brownian absorbing theofdensity n transitio the

2)(

exp 2

1det)|,(f

formula,McGregor -Karlin theof By vietue ).A typeofchamber (Weyl ...: Let

,....2,1,0 ),( walk random theofion interpolat thebe toconsidered here is )( where

, )],0([ paths continuous of space on the , 1 , . )(1Q) . (

measuresy probabilitconsider we, ,0For

.,...,2,1,0 , )(...)()( ; time toupcondition ngnoncollidi with the walk vicious thedenotes )Q,)}(({hat Remember t

2

,1

121

2

21

,...2,1,0

2

xyxR

R

Rx

R

xy

RxRSS

RS

Zx

S

xx

x

tdt NN

N

N

N

N

kjNkjN

NNNN

NTLL,T

NN

t

tyx

tt

xxxttt

TCLtLL

T

TttStStSTt

∫=<

>

∈•

=

⎥⎥⎦

⎢⎢⎣

⎪⎭

⎪⎬⎫

⎪⎩

⎪⎨⎧ −−=

•<<<∈=•

=

→≥⎟⎠⎞

⎜⎝⎛ ∈=

∈>•

=<<<

<

<

<

≤≤

−<

<

=

π

μ

Page 21: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

21Theorem 1.

. || ),2/(/2 ,(0,0,...0) where,, ,0for

,),(N

),(N)|,(f),;,(g

),,(N)(2

||exp),;,0(g

densityy probabilitn transitiowith the],,0[ , ))(),...,(),(()( processdiffusion ousinhomogeney temporall theof law the

weakly toconverges ) . ( , as ,0 and fixedany For

1

22

1

2/4/)1(2/

,

1

2

,

21

,

2

∑∏

==

−−−<

≤<≤

<

=Γ==∈≤<≤

−−−

=

−−⎭⎬⎫

⎩⎨⎧−×=

∈=

∞→>∈

N

jj

N

j

NNNNN

N

NNTN

NNji

ijTN

N

TLN

yjtTcTts

sTtTstts

tTyyt

ct

TttXtXtXt

LT

y0Ryx

xyxyyx

yyy0

X

Zx xμ

Page 22: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

22

Corollary 2.

motions.Brownian standardt independen denote )}({ where

,,...,2,1 ),,0[ , )()(

1)()(

:modelmotion Brownian sDyson' of equations thesolves )( processdiffusion The (ii)

.)(/)2(' where,, ,0for

)()(h with (y)h)|,(f)(h

1),;,(p

,)(h2

||exp '),;,0(p

densityy probabilitn transitiowith the),,0[ , ))(),...,(),(()(

processdiffusion shomogeneouy temporall theof law the weakly toconverges ) . ( , as ,0 and fixedany For

. as with offunction increasingan be Let (i)

1

,1

1

2/2/

1

2

21

,

2

2

Nii

ijNj jiii

N

j

NNN

jNkj

kNNNN

N

NN

N

TLN

LL

tB

NitdttYtY

tdBtdY

t

jtcTts

xxstts

tct

ttYtYtYt

LT

LTLT

=

≠≤≤

=

−−<

≤<≤

<

=∞∈−

+=

Γ=∈≤<≤

−=−=

⎭⎬⎫

⎩⎨⎧−×=

∞∈=

∞→>∈

∞→∞→

Y

Ryx

xxyx

yx

yyy0

Y

Zx x

π

μ

Next we consider the case that the noncolliding

time-period

T=TL goes to infinity.

Page 23: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

23

REMARKS:

When all the particles are starting from the origin 0,

The Process Y(t)

= NONCOLLIDING Browniam

Motions

2)(e 2

1),;,0(p 11

2/2

iNji

j

N

k

tkyN yy

tt −×

⎭⎬⎫

⎩⎨⎧∝ ∏∏

≤<≤=

πy0

Product of Independent Gaussian Distributions

Strong Repulsive Interactions

. 0),;,0(p ,0|| As →→− y0 tyy Nij

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24

REMARKS:

Here we set N = 3 as an example.

The process

Y(t) is identified with Dyson’s Brownian motion model

( ) ( )( )⎥⎥⎥

⎢⎢⎢

−−−−−−−−−

×=)|,G()|,G()|,G()|,G()|,G()|,G()|,G()|,G()|,G(

det)(h)(h,,,;,,,p

333231

232221

131211

321321

xystxystxystxystxystxystxystxystxyst

yyytxxxsN

NN x

y

h-transform

in the sense of Doob

Karlin-McGregor formulaLindstrom-Gessel-Viennot

formula

. )()(h ,kernel)(heat

)(2

)(exp)(2

1)|,(

1

2

iNji

jN xxx

styx

stxystG

−=

⎭⎬⎫

⎩⎨⎧

−−

−−

=−

∏≤<≤

π

Page 25: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

25

Dyson’s Brownian motion model1.

For all t > 0, with Probability 1.

2.

The process is given as a solution of the stochastic differential equations,

where Bi (t) are independent standard Brownian motions i =1, 2 ,…, N .

Nt <∈RY )(

[ )∞∈≤≤−

+= ∑≠≤≤

,0,1)()(

1)()(,1:

tNidttYtY

tdBtdYijNjj ji

ii

• Strong repulsive forces

among any pair of particlesdistance particle1

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26Remark.

HERMITIAN MATRIX-VALUED PROCESS

AND DYSON’S BROWNIAN MOTION MODEL

•Let be mutually independent (standard one-dim.) Brownianmotions started from the origin. Define

,,1),(~),( NjitBtB ijij ≤≤

⎪⎪⎩

⎪⎪⎨

>−

=

<

=

⎪⎪⎩

⎪⎪⎨

>

=

<

=

)()(~2

1)(0

)()(~2

1

)(

)()(2

1)()(

)()(2

1

)(

jitB

ji

jitB

ta

jitB

jitB

jitB

ts

ij

ij

ij

ij

ii

ij

ij

•Consider the Hermitian

Matrix-Valued

stochastic processNN ×( ) ( )

NjiijijNjiij tatstt≤≤≤≤

−+==Ξ,1,1

)(1)()()( ξThat is,

⎟⎟⎟⎟⎟⎟⎟⎟

⎜⎜⎜⎜⎜⎜⎜⎜

−−−−−−

−+−−−−−+−+−−−+−+−+

)(...)(1)()(1)()(1)(..............................

)(1)(...)()(1)()(1)()(1)(...)(1)()()(1)()(1)(...)(1)()(1)()(

)(

332211

333323231313

222323221212

111313121211

tstatstatstats

tatststatstatstatstatststatstatstatstatsts

t

NNNNNNNN

NN

NN

NN

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27

•Consider the variation of the matrix, It is clear that

And by the previous observation, we find that

They are summarized as

Since is a Hermitian

matrix-valued process,at each time t there is a Unitary Matrix

, such that

where the eigenvalues

are in the increasing order

We can regard

as an N-particle stochastic process in one dimension.

)(tΞ

( )Njiij tdtd

≤≤=Ξ

,1)()( ξ

),1(0)( Njitd ij ≤≤=ξ

( )

( ) )1()(

)1()()()()(

)1(0)(

2

*

2

Nidttd

Njidttdtdtdtd

Njitd

ii

ijijjiij

ij

≤≤=

≤≠≤==

≤≠≤=

ξ

ξξξξ

ξ

),,,1()()( Nnkjidttdtd jkinknij ≤≤= δδξξ

Njiij tutU ≤≤= ,1))(()({ })(),....,(),(diag)()()()( 21 tttttUttU Nλλλ=Λ=Ξ+

[ )∞∈∀≤≤≤ ,0),(....)()( 21 tttt Nλλλ

( ) NN tttt Rλ ∈≡ )(),....,(),()( 21 λλλ

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28

QUESTIONBy the diagonalization

of the matrix, what kind of interactions emerge

among the N particles in the process ?)(tλ

•From now on we assume that

•And we consider the following conditional configuration-spaceof one-dim. N particles,

(This is called the Weyl

chamber of type . )

)0(....)0()0( 21 Nλλλ <<<

{ }NNA

N xxx <<<∈= ....: 21RxW

1−NA

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29

ANSWER 1 (by Dyson 1962)1.

For all t > 0, with Probability 1.

2.

The process is given as a solution of the stochastic differential equations,

where are independent standard one-dim. Brownian motions .

ANt Wλ ∈)(

[ )∞∈≤≤∑−

+=≠≤≤

,0,1)()(

1)()(,1:

tNidttt

tdBtdijNjj ji

ii λλλ

)(tBi )1( Ni ≤≤

• This process is called Dyson’s Brownian motion model.

• Strong repulsive forces

emerge among any pair of particles distance particle1

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30

• Let

•Consider

It solves the Fokker-Planck (FP) equation in the form

( )⎪⎩

⎪⎨

=≤≤∂∂

=∑−

=

−∏=

≠≤≤

≤<≤

)(),....,(),()( , )1( )h( ln1)(

)sdifference ofproduct ( )()h(

21,1:

1

xxxxbxx

x

Ni

ijNjjji

i

iNji

j

bbbNixxx

b

xx

[ ]. )...., , ,( ), ...., , ,( where

,)( to)( fromdensity y probabilittransition),;,p(

2121 NN yyyxxxtsts

=====

yxyλxλyx

),;,p()(),;,p(21),;,p( yxxbyxyx xx tststs

t∇⋅+Δ=

∂∂

ANSWER 2Introduce a determinant

Then the solution of the FP equation is given by

If (all particles starting from the origin)

[ ] tj

yi

x

ijijNji txytxytt

2/2)(

,1e

21)|,G( with )|,G(det)|,f(

−−

≤≤==

πxy

. , ,0for )h()|,f()h(

1),;,p( ANtsstts Wyxyxy

xyx ∈∞<<<−=

,0at )0,....,0,0( ==→ s0x

∏Γ=∑=⎭⎬⎫

⎩⎨⎧−=

==

− N

i

NN

ii

NiCy

tCtt

1

2/1

1

2222

1

2/2

. )()2( , || where)h(2

||exp),;,0p( πyyyy0

Page 31: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

31

Noncolliding

Diffusion Processes

Random Matrix TheoryMatrix Models in Statistical Phys.

andString Theory, etc…..

Infinite Systems of Noncolliding

Diffusion Particles

Theory of Entire Functions

Representation Theory

ofLie Algebra/Lie Groups

I hope …..Statistical PhysicsProbability Theory

Other Fields of

(Infinite) Particle Systems

Noncolliding Processes Mathematics

Remaks

limit functions ncorrelatio of

sexpression taldeterminan

∞→N

Enumerative CombinatoricsYoung TableauxSymmetric FunctionsVicious Walker Model

Diffusion Scaling limit

Page 32: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

32

6. Temporally Inhomogeneous Noncolliding

Brownian Motions

. || ),2/(/2

,(0,0,...0) where,, ,0for

,),(N

),(N)|,(f),;,(g

),,(N)(2

||exp),;,0(g

densityy probabilitn transitiowith the],,0[ , ))(),...,(),(()(

The

1

22

1

2/4/)1(2/

,

1

2

,

21

2

∑∏

==

−−−

<

≤<≤

=Γ=

=∈≤<≤

−−−

=

−−⎭⎬⎫

⎩⎨⎧−×=

∈=

N

jj

N

j

NNNN

NN

NNTN

NNji

ijTN

N

yjtTc

Tts

sTtTstts

tTyyt

ct

TttXtXtXt

y

0Ryx

xyxyyx

yyy0

X process diffusion ousinhomogene temporally

. ),0[ , )( lim)( processdiffusion shomogeneouy temporallThe∞∈= ∞→ ttt T XY

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33Case t = T

Case ∞→T

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34

Transition in Time of Particle Distribution• This observation implies that there occurs a transition.

For a finite but large T

Ttxxyt

tg jNkj

k

N

iTN i <<<−

⎭⎬⎫

⎩⎨⎧−∝ ∏∑

≤<≤=

0for )(21exp),;,0( 2

11,

2y0

As the time

t goes on from 0

to T

TtxxyT

Tg jNkj

k

N

iTN i =−

⎭⎬⎫

⎩⎨⎧−∝ ∏∑

≤<≤=

at )(21exp),;,0(

11,

2y0

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35

Three Standard (Wigner-Dyson) Random Matrix Ensembles

[1]

The distribution of Eigenvalues

of Hermitian

Matricesin the Gaussian Unitary Ensemble (GUE)

is given in the form

[2]

The distribution of Eigenvalues

of Real Symmetric Matricesin the Gaussian Orthogonal Ensemble (GOE)

is given in the form

[3]

The distribution of Eigenvalues

of Quternion

Self-Dual HermitianMatrices

in the Gaussian Symplectic

Ensemble (GSE)

is given in the form

2)(2

1exp11

22 j

Nkjk

N

ii λλλ

σ−

⎭⎬⎫

⎩⎨⎧− ∏∑

≤<≤=

NN ×

NN ×

NN ×

)(2

1exp11

22 j

Nkjk

N

ii λλλ

σ−

⎭⎬⎫

⎩⎨⎧− ∏∑

≤<≤=

4)(2

1exp11

22 j

Nkjk

N

ii λλλ

σ−

⎭⎬⎫

⎩⎨⎧− ∏∑

≤<≤=

Page 36: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

36•Let be mutually independent standard Brownian motions

started from the origin. Define,,1),(~),( NjitBtB ijij ≤≤

bridges)(Brownian ].,0[ ,1 , )(

)(~)( where

,

)()(2

1)(0

)()(2

1

)(

)()(2

1)()(

)()(2

1

)(

0

TtNjidssTs

tBt

jit

ji

jit

ta

jitB

jitB

jitB

ts

tij

ijij

ij

ij

ij

ij

ii

ij

ij

∈≤<≤−

−=

⎪⎪

⎪⎪

>−

=

<

=

⎪⎪

⎪⎪

>

=

<

=

∫β

β

β

β

•Consider the Hermitian

Matrix-Valued

stochastic processNN ×

( ) ( )NjiijijNjiijTN tatstt

≤≤≤≤−+==Ξ

,1,1, )(1)()()( ξThat is,

⎟⎟⎟⎟⎟⎟⎟⎟

⎜⎜⎜⎜⎜⎜⎜⎜

−−−−−−

−+−−−−−+−+−−−+−+−+

)(...)(1)()(1)()(1)(..............................

)(1)(...)()(1)()(1)()(1)(...)(1)()()(1)()(1)(...)(1)()(1)()(

)(

332211

333323231313

222323221212

111313121211

,

tstatstatstats

tatststatstatstatstatststatstatstatstatsts

t

NNNNNNNN

NN

NN

NN

TN

Page 37: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

37

Since is a Hermitian

matrix-valued process,at each time t there is a Unitary Matrix

, such that

where the eigenvalues

are in the increasing order

We can regard

as an N-particle stochastic process in one dimension.

We have proved the following theorem.

)(tΞ

Njiij tutU ≤≤= ,1))(()({ })(),....,(),(diag)()()()( 21 tttttUttU Nλλλ=Λ=Ξ+

[ )∞∈∀≤≤≤ ,0),(....)()( 21 tttt Nλλλ

( ) NN tttt Rλ ∈≡ )(),....,(),()( 21 λλλ

TheoremThe eigenvalue

process

is equivalent

in distribution

with

the system of

noncolliding

Brownian motions

X(t)with the initial condition X(0)=0 (i.e. all particles start from

the origin),

which are obtained as the scaling limit of vicious walker model.

( ))(),....,(),()( 21 tttt Nλλλ≡λ

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387. PATTERNS of NONCOLLIDING PATHS

AND RANDOM MATRIX THEORIES7.1 STAR CONFIGURATIONS• There occurs a transition in distribution from GUE to GOE.

This temporal transition can be decribed

by the Two-Matrix Model

of Pandey

and Mehta, in which a Hermitian

random matrix is coupled with a real symmetric random matrix.See Katori and Tanemura, PRE 66

(2002) 011105/1-12.•

Techniques developed for multi-matrix models

can be used to evaluate the dynamical correlation functions. Quaternion determinantal

expressions

are derived.See Nagao, Katori and Tanemura, Phys. Lett. A307 (2003) 29-35.

• Using the exact correlation functions, we can discuss the scaling limits

ofinfinite particles and the infinite time-period .

See Katori, Nagao and Tanemura, Adv.Stud.Pure

Math. 39 (2004) 283-306.∞→N ∞→T

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39

7.2 Watermelon Configurations• Consider a finite time-period [0,T] and set

y=0

at the initial time t=0 and the final time t=T.• The transition probability density is given as

• The distribution is kept in the form of GUE.• Only the variance

changes as a function of t as .

( )2)h(

/12||exp11),;,0(q2

1

2/2

watermelon yy0⎭⎬⎫

⎩⎨⎧

−−

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛ −=

Ttty

Ttt

Ct

N

⎟⎠⎞

⎜⎝⎛ −=

Ttt 12σ

Page 40: Part 2 From Vicious Walk Model to Random Matrix …...1 Part 2 From Vicious Walk Model to Random Matrix Theory 中央大学理工学部 香取眞理 (かとりまこと) 集中講義:東京大学大学院理学系研究科物理学専攻

40

7.3 Banana Configurations• Consider 2N particle system. Set y=0

at the initial time

t=0.

At the final time

t=T, we assume the following Pairing of Particle Positions.

• The transition probability density is given by

• As , there occurs a transition from the GUE distribution to the GSE distribution.

. .... with ,.... , , 12312124321 −− <<<=== NNN yyyyyyyyy

. )|,G()|,G(det),(N where

, , ,0for ),(N

),(N)|,f(),;,0(q

1,21

2

banana

banana

bananabanana

⎥⎦⎤

⎢⎣⎡

∫=

∈≤<<−

=

≤≤≤≤ iji

ijNjNi

AN

xyttxxytxt

TtsT

tTtt

ANW

Wyxx

yxyyx

Tt →= 0

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41

7.4 Star Configurations with Absorbing Wall• Put an Absorbing Wall

at the origin. Consider the N Brownian particles started from 0

conditioned never to collide with each other nor to collide with the wall.• This is identified with the h-transform of the N-dim. Absorbing Brownian motion in

• For , we can obtain a process showing a transition fromthe class C

distribution

of Altland

and Zirnbauer

(1996);

to the class CI distribution

(studied for a theory of quantum dots)

{ } ). typeofchamber (Weyl ....0: 21 NNNC

N Cxxxx <<<<∈= RW

∞<T

Ttyyyt

tN

kki

Njij

C <<<−⎭⎬⎫

⎩⎨⎧−∝ ∏∏

=≤<≤0for )(

2||exp),;,0(q

1

222

1

22yyx

.at )(2

||exp),;,0(q1

2

1

22

TtyyyT

TN

kki

Njij

C =−⎭⎬⎫

⎩⎨⎧−∝ ∏∏

=≤<≤

yyx

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42

7.5 Star Configurations with Reflection Wall• Put a reflection wall

at the origin. Consider the N Brownian particles started form 0

conditioned never to collide with each other.• This is identified with the h-transform of the N-dim. Absorbing Brownian motion in

{ } ). typeofchamber (Weyl ....|:| 21 NNND

N Dxxxx <<<∈= RW

For , we can obtain a process showing a transition from the class D distribution

of Altland

and Zirnbauer

(1996);

to the ``real”

class D distribution

∞<T

Ttyyt

t iNji

jD <<<−

⎭⎬⎫

⎩⎨⎧−∝ ∏

≤<≤0for )(

2||exp),;,0(q 22

1

22yyx

.at )(2

||exp),;,0(q 2

1

22

TtyyT

T iNji

jD =−

⎭⎬⎫

⎩⎨⎧−∝ ∏

≤<≤

yyx

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43

7.6 Banana Configurations with Reflection Wall• Put a reflection wall

at the origin.

• Consider the 2N Brownian particles started from 0 in Banana configurations.

• For , we can obtain a process showing a transition from the class D distribution

of Altland

and Zirnbauer

To the class DIII

distribution.Ttyy

tt i

Njij

D <<<−⎭⎬⎫

⎩⎨⎧−∝ ∏

≤<≤0for )(

2||exp),;,0(q 22

1

22

, banana yyx

∞<T

.at )(||exp),;,0(q1

122

121

212

24

oddbanana , Ttyyy

TT

N

kki

Njij

D =∏−∏⎭⎬⎫

⎩⎨⎧−∝

=−−

≤<≤−

yyx

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447.7 CONCLUDING REMARKS

• There are 10 CLASSES

of Gaussian Random Matrix Theories.

Standard (Wigner-Dyson)GUE

Star configurations

GOEGSE

Banana configurations

Nonstandard (chiral

random matrices)

Particle Physics of QCDchGUEchGOE

Realized by Noncolliding

Systems of

chGSE

2D Bessel processes

and Generalized MeandersNonstandard (Altland-Zirnbauer)

Mesoscopic

Physics with Superconductivity

class Cclass CI

Star config. with Absorbing Wall

class Dclass DIII

Banana config. With Reflection Wall

All of the 10 eigenvalue-distributions can be realized by the Noncolliding

Diffusion Particle Systems (Vicious Walks).

See Katori and Tanemura, J.Math.Phys.(2004)

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45

Noncolliding

Diffusion Processes

Random Matrix TheoryMatrix Models in Statistical Phys.

andString Theory, etc…..

Infinite Systems of Noncolliding

Diffusion Particles

Theory of Entire Functions

Representation Theory

ofLie Algebra/Lie Groups

I hope …..Statistical PhysicsProbability Theory

Other Fields of

(Infinite) Particle Systems

Noncolliding Processes Mathematics

8. Remaks

(again)

limit functions ncorrelatio of

sexpression taldeterminan

∞→N

Enumerative CombinatoricsYoung TableauxSymmetric FunctionsVicious Walker Model

Diffusion Scaling limit

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小林奈央樹 et. al. : Phys. Rev. E 78 (2008) 051102