2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG...

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2D Ising model 16. 7. 8. RG Fixed point Onsager (1944 ) Can we solve for ? Partition function 1

Transcript of 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG...

Page 1: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

2D Ising model

16. 7. 8.

RG Fixed point

Onsager (1944)

Can we solve for ?

Partition function

1

Page 2: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

S-행렬

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•  무한개의 보존전하 à 완전탄성산란행렬

•  S-행렬로부터 정확한 물리량 계산가능 공간

시간

2

Page 3: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

16. 7. 8.

•  Pole of S à bound state [구속입자] –  (ex) 양자역학의 delta함수 퍼텐샬

– Bound state energy:

– Scattering amplitudes: (E>0)

Griffiths pp.73-74

Pole at

3

Page 4: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

Bootstrap

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Page 5: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

Exact results

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•  S-matrices by Zamolodchikov (1988)

•  Mass spectrum from poles of S-matrices

Perron-Frobenius vector of Cartan matrix

황금비

5

Page 6: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

•  2D Ising model = 1D Ising spin chain

•  Material: CoNb2O6

Experimental evidence of E8

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Critical Ising model

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Page 7: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

R Coldea et al. Science 2010;327:177-180

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Page 8: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

(A) Cartoon of a neutron spin-flip scattering that creates a pair of independently propagating kinks in a ferromagnetically ordered chain.

R Coldea et al. Science 2010;327:177-180

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Page 9: 2D Ising modelk2.ewha.ac.kr/psi/PSI-IsingE8.pdf · 2016. 7. 7. · 2D Ising model 16. 7. 8. RG Fixed point Onsager (1944) Can we solve for ? Partition function 1

(A and B) Energy scans at the zone center at 4.5 and 5 T observing two peaks, m1 and m2, at low energies.

R Coldea et al. Science 2010;327:177-180

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