"Renormalization"의 두 판 사이의 차이

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<h5 style="margin: 0px; line-height: 2em;">electroweak renormalization</h5>
 
<h5 style="margin: 0px; line-height: 2em;">electroweak renormalization</h5>
  
*  spontaneous local symmetry breaking or Higgs mechanism<br>
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*  spontaneous local [[search?q=symmetry%20breaking&parent id=3693987|symmetry breaking]] or Higgs mechanism<br>
*  mass term for gauge field is zero in the Lagranaian, but these bosons have mass<br>
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*  mass term for gauge field is zero in the Lagranaian, but these bosons (W,Z bosons) have mass term. To resolve this, we employ Higgs mechanism<br>
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2011년 10월 12일 (수) 12:30 판

renormalization
  • way of pulling out sensible answers from Feynman diagrams that explode
  • there are two parts in the renormalization program
    • regularization - the divergences must be written down in some way so that they can be compared, added and subtracted
    • renormalization proper - the various divergences must be gathered together and extracted from the rest of the calculation

 

 

regularization
  • root of the problem
    • probability of creating particles of colossal energies
    • in terms of Feynman diagrams, the momentum in a loop can run away to infinity
  • dimensional regularization
    • regularization scheme (especially good in QCD)
    • regard the dimension as a continuous quantity
    • coupling constant changes accordingly as the dimension changes continuously
    • we get a new parameter called regularization scheme

 

 

QED renormalization

 

 

electroweak renormalization
  • spontaneous local symmetry breaking or Higgs mechanism
  • mass term for gauge field is zero in the Lagranaian, but these bosons (W,Z bosons) have mass term. To resolve this, we employ Higgs mechanism

 

 

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