"An analogue of Rogers-Ramanujan continued fraction"의 두 판 사이의 차이

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26번째 줄: 26번째 줄:
  
 
 
 
 
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<h5 style="line-height: 2em; margin: 0px;">analogue</h5>
  
 
 
 
 
  
*   <br> A=1/2 (3,5) minimal model<br><math>\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}+\frac{n}{2}}} {(q;q)_n} \sim \frac{2}{\sqrt{5+\sqrt{5}}}\exp(\frac{\pi^2}{10t}+\frac{t}{40})+o(t^5)</math><br><math>\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}}} {(q;q)_n}\sim \frac{2}{\sqrt{5-\sqrt{5}}}\exp(\frac{\pi^2}{10t}-\frac{t}{40})+o(t^5)</math><br>
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A=1/2 (3,5) minimal model
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<math>\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}+\frac{n}{2}}} {(q;q)_n} \sim \frac{2}{\sqrt{5+\sqrt{5}}}\exp(\frac{\pi^2}{10t}+\frac{t}{40})+o(t^5)</math>
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<math>\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}}} {(q;q)_n}\sim \frac{2}{\sqrt{5-\sqrt{5}}}\exp(\frac{\pi^2}{10t}-\frac{t}{40})+o(t^5)</math>
  
 
 
 
 
52번째 줄: 58번째 줄:
  
 
<math>R(z)=R(zq^{1/a})+z^{a}q^{b}R(zq^{2b/a})</math> i.e.
 
<math>R(z)=R(zq^{1/a})+z^{a}q^{b}R(zq^{2b/a})</math> i.e.
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<math>R(z)=R(zq)+zq^{1/4}R(zq^{1/2})</math>
  
 
<math>R(z)=R(zq)+zq^{1/4}R(zq^{1/2})</math>
 
<math>R(z)=R(zq)+zq^{1/4}R(zq^{1/2})</math>

2010년 3월 25일 (목) 09:02 판

Rogers-Ramanujan

A=2 (2,5) minimal model

\(\sum_{n=0}^\infty \frac {q^{n^2+n}} {(q;q)_n} \sim \sqrt\frac{2}{5+\sqrt{5}}\exp(\frac{\pi^2}{15t}+\frac{11t}{60})+o(1)\)

\(\sum_{n=0}^\infty \frac {q^{n^2}} {(q;q)_n} \sim \sqrt\frac{2}{5-\sqrt{5}}\exp(\frac{\pi^2}{15t}-\frac{t}{60})+o(1)\)

 

\(R(z)=R(zq)+zqR(zq^2)\)

 

이 정리로부터 \(R(q^n)=R(q^{n+1})+q^{n+1}R(q^{n+2})\)

즉 \(\frac{R(q^{n+1})}{R(q^n)}=\cfrac{1}{1+q^{n+1}\cfrac{R(q^{n+2})}{R(q^{n+1})}}\)를 얻는다.

 

\(\frac{H(q)}{G(q)}=\cfrac{R(q)}{R(1)} = \cfrac{1}{1+q\cfrac{R(q^2)}{R(q)}}=\cfrac{1}{1+\cfrac{q}{1+q^2\cfrac{R(q^3)}{R(q^2)}}}=\cdots\)

이를 반복하면, 다음을 얻는다.

\(\frac{H(q)}{G(q)} = \cfrac{1}{1+\cfrac{q}{1+\cfrac{q^2}{1+\cfrac{q^3}{1+\cdots}}}}\)

 

analogue

 

A=1/2 (3,5) minimal model

\(\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}+\frac{n}{2}}} {(q;q)_n} \sim \frac{2}{\sqrt{5+\sqrt{5}}}\exp(\frac{\pi^2}{10t}+\frac{t}{40})+o(t^5)\)

\(\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}}} {(q;q)_n}\sim \frac{2}{\sqrt{5-\sqrt{5}}}\exp(\frac{\pi^2}{10t}-\frac{t}{40})+o(t^5)\)

 

 

recurrence relation

\(R(z)=\sum_{n\geq 0}\frac{z^nq^{n^2/4}}{(1-q)\cdots(1-q^n)}\)

\(H(q)=R(q^{1/2})=\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}+\frac{n}{2}}} {(q;q)_n} \sim \frac{2}{\sqrt{5+\sqrt{5}}}\exp(\frac{\pi^2}{10t}+\frac{t}{40})+o(t^5)\)

\(G(q)=R(1)=\sum_{n=0}^\infty \frac {q^{\frac{n^2}{4}}} {(q;q)_n}\sim \frac{2}{\sqrt{5-\sqrt{5}}}\exp(\frac{\pi^2}{10t}-\frac{t}{40})+o(t^5)\)

 

(정리)

\(a=1,b=1/4\)

\(R(z)=R(zq^{1/a})+z^{a}q^{b}R(zq^{2b/a})\) i.e.

\(R(z)=R(zq)+zq^{1/4}R(zq^{1/2})\)

\(R(z)=R(zq)+zq^{1/4}R(zq^{1/2})\)