"Braid group"의 두 판 사이의 차이

수학노트
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imported>Pythagoras0
 
(사용자 2명의 중간 판 3개는 보이지 않습니다)
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** <math>\sigma_i\sigma_{i+1}\sigma_i = \sigma_{i+1}\sigma_i \sigma_{i+1}</math> for <math>i = 1,..., n-2</math>
 
** <math>\sigma_i\sigma_{i+1}\sigma_i = \sigma_{i+1}\sigma_i \sigma_{i+1}</math> for <math>i = 1,..., n-2</math>
 
* [[Yang-Baxter equation (YBE)]]
 
* [[Yang-Baxter equation (YBE)]]
* For a solution of the YBE $\bar{R}$, we can construct a representation $\rho$ of the braid group by
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* For a solution of the YBE <math>\bar{R}</math>, we can construct a representation <math>\rho</math> of the braid group by
$$
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:<math>
 
\rho : B_n \to \rm{Aut}(V^{\otimes n})
 
\rho : B_n \to \rm{Aut}(V^{\otimes n})
$$ where $\rho(\sigma_i)=\bar{R}_i$
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</math> where <math>\rho(\sigma_i)=\bar{R}_i</math>
  
  
There is also a natural surjective morphism from $B_n$ to the symmetric group $\mathfrak{S}_n$, given  on the generators by $B_n\ni\sigma_i\mapsto s_i\in \mathfrak{S}_n$, $i=1,\dots,n-1$. For a braid $\beta\in B_n$, we denote $p_{\beta}$ its image in $\mathfrak{S}_n$, and refer to $p_{\beta}$ as to the underlying permutation of $\beta$.
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There is also a natural surjective morphism from <math>B_n</math> to the symmetric group <math>\mathfrak{S}_n</math>, given  on the generators by <math>B_n\ni\sigma_i\mapsto s_i\in \mathfrak{S}_n</math>, <math>i=1,\dots,n-1</math>. For a braid <math>\beta\in B_n</math>, we denote <math>p_{\beta}</math> its image in <math>\mathfrak{S}_n</math>, and refer to <math>p_{\beta}</math> as to the underlying permutation of <math>\beta</math>.
  
  
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[[파일:Braid.png]]
 
[[파일:Braid.png]]
 
* read the braid word from left to right accordingly.
 
* read the braid word from left to right accordingly.
* For instance, the braid word corresponding to the braid above is $\sigma_1^{-1}\sigma_2\sigma_1^{-1}\sigma_2\sigma_1^{-1}$
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* For instance, the braid word corresponding to the braid above is <math>\sigma_1^{-1}\sigma_2\sigma_1^{-1}\sigma_2\sigma_1^{-1}</math>
  
 
==Markov moves==
 
==Markov moves==
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[[분류:개인노트]]
 
[[분류:개인노트]]
 
[[분류:math and physics]]
 
[[분류:math and physics]]
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[[분류:migrate]]
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==메타데이터==
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===위키데이터===
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* ID :  [https://www.wikidata.org/wiki/Q220409 Q220409]
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===Spacy 패턴 목록===
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* [{'LOWER': 'braid'}, {'LEMMA': 'group'}]

2021년 2월 17일 (수) 02:36 기준 최신판

review of symmetric groups

  • 원소의 개수가 n인 집합의 전단사함수들의 모임
  • \(n!\) 개의 원소가 존재함
  • 대칭군의 부분군은 치환군(permutation group)이라 불림



presentation of symmetric groups

  • \(S_n\)
  • generators \(\sigma_1, \ldots, \sigma_{n-1}\)
  • relations
    • \({\sigma_i}^2 = 1\)
    • \(\sigma_i\sigma_j = \sigma_j\sigma_i \mbox{ if } j \neq i\pm 1\)
    • \(\sigma_i\sigma_{i+1}\sigma_i = \sigma_{i+1}\sigma_i\sigma_{i+1}\)


presentation of braid groups

  • \(B_n\)
  • generators \(\sigma_1,...,\sigma_{n-1}\)
  • relations (known as the braid or Artin relations):
    • \(\sigma_i\sigma_j =\sigma_j \sigma_i\) whenever \(|i-j| \geq 2 \)
    • \(\sigma_i\sigma_{i+1}\sigma_i = \sigma_{i+1}\sigma_i \sigma_{i+1}\) for \(i = 1,..., n-2\)
  • Yang-Baxter equation (YBE)
  • For a solution of the YBE \(\bar{R}\), we can construct a representation \(\rho\) of the braid group by

\[ \rho : B_n \to \rm{Aut}(V^{\otimes n}) \] where \(\rho(\sigma_i)=\bar{R}_i\)


There is also a natural surjective morphism from \(B_n\) to the symmetric group \(\mathfrak{S}_n\), given on the generators by \(B_n\ni\sigma_i\mapsto s_i\in \mathfrak{S}_n\), \(i=1,\dots,n-1\). For a braid \(\beta\in B_n\), we denote \(p_{\beta}\) its image in \(\mathfrak{S}_n\), and refer to \(p_{\beta}\) as to the underlying permutation of \(\beta\).


examples

  • in a braid diagram, read from bottom to top and we number all strands of the braid with the indices it starts at the bottom

파일:Braid.png

  • read the braid word from left to right accordingly.
  • For instance, the braid word corresponding to the braid above is \(\sigma_1^{-1}\sigma_2\sigma_1^{-1}\sigma_2\sigma_1^{-1}\)

Markov moves

  • braid group version of Reidemeister moves


computational resource



related items

encyclopedia


expositions

메타데이터

위키데이터

Spacy 패턴 목록

  • [{'LOWER': 'braid'}, {'LEMMA': 'group'}]