"Spin system and Pauli exclusion principle"의 두 판 사이의 차이

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<h5>angular momentum</h5>
  
 
 
 
 
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<h5 style="line-height: 2em; margin: 0px;">sl(2)</h5>
 
<h5 style="line-height: 2em; margin: 0px;">sl(2)</h5>
  
*  3차원 리대수<br><math>E=</math><br><math>F</math><br><math>H=\begin{pmatrix} 1&0\ 0&-1 \end{pmatrix}</math><br>
 
 
*  commutator<br><math>[E,F]=H</math><br><math>[H,E]=2E</math><br><math>[H,F]=-2F</math><br>
 
*  commutator<br><math>[E,F]=H</math><br><math>[H,E]=2E</math><br><math>[H,F]=-2F</math><br>
  
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*  Bosons<br>
 
*  Bosons<br>
* photon
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** photon
* vector boson<br>
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** vector boson
* Gluon<br>
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** Gluon
* follows Bose-Einstein statistics<br>
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** follows Bose-Einstein statistics
* force-transmitting particles<br>
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** force-transmitting particles
 
 
*  
 
 
 
 
 
 
 
 
*  Fermions = spin- <math>1/2</math> particles<br>
 
*  Fermions = spin- <math>1/2</math> particles<br>
 
**  quarks and leptons<br>
 
**  quarks and leptons<br>
 
**  follows Fermi-Dirac statistics<br>
 
**  follows Fermi-Dirac statistics<br>
**  matter particles<br>
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**   <br> matter particles<br>
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2010년 11월 3일 (수) 18:56 판

introduction
  • the simplest example of quantum mechanical system
  • quantization of the angular momentum
  • measures as being some multiple of Planck's constant divided by 2pi

 

 

angular momentum

 

 

representation theory
  • concept from the representation of  \(SU(2)\)
  • half of highest weight is called the spin of the module
    • Casimir operator can also detect this number.
  • spin \(1/2\) is the most important case since they are the matter particles
  • this is why we have half-integral spin although those representation are integral highest weight representations.

 

 

operator formulation
  • 파울리 행렬 (해밀턴의 사원수 참조)
    \(\sigma_1 = \sigma_x = \begin{pmatrix} 0&1\\ 1&0 \end{pmatrix} \)
    \(\sigma_2 = \sigma_y = \begin{pmatrix} 0&-i\\ i&0 \end{pmatrix} \)
    \(\sigma_3 = \sigma_z = \begin{pmatrix} 1&0\\ 0&-1 \end{pmatrix}\)
  • raising and lowering 연산자
    \(\sigma_{\pm}=\frac{1}{2}(\sigma_{x}\pm i\sigma_{y})\)
    \(\sigma_{+}=\frac{1}{2}(\sigma_{x}+ i\sigma_{y})=\begin{pmatrix} 0&1\\ 0&0 \end{pmatrix}\)
    \(\sigma_{-}=\frac{1}{2}(\sigma_{x}- i\sigma_{y})=\begin{pmatrix} 0&0\\ 1&0 \end{pmatrix}\)
    \([\sigma_{z},\sigma_{\pm}]=\pm 2\sigma_{\pm}\)

 

 

sl(2)
  • commutator
    \([E,F]=H\)
    \([H,E]=2E\)
    \([H,F]=-2F\)

 

 

spin particle statstics
  • Bosons
    • photon
    • vector boson
    • Gluon
    • follows Bose-Einstein statistics
    • force-transmitting particles
  • Fermions = spin- \(1/2\) particles
    • quarks and leptons
    • follows Fermi-Dirac statistics
    •  
      matter particles

 

 

history

 

 

related items

 

 

encyclopedia

 

 

books

 

 

 

expositions

 

 

 

articles

 

 

 

question and answers(Math Overflow)

 

 

blogs

 

 

experts on the field

 

 

links