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advanced_tools:wigners_little_groups

Explanations in this section should contain no formulas, but instead colloquial things like you would hear them during a coffee break or at a cocktail party.

The little group is a subgroup of the Poincare group which leaves the four-momentum of a given particle invariant. The little groups for massive and massless particles are locally isomorphic to the three-dimensional rotation group and the two-dimensional euclidean group respectively. GAUGE TRANSFORMATIONS AS LORENTZ-BOOSTED ROTATIONS by D. HAN et. al.

- A good explanation can be found at page 8 in https://indico.cern.ch/event/544849/contributions/2214530/attachments/1301154/1942518/yskim.pdf
- Another great introduction is section 2 here https://arxiv.org/pdf/1709.04891.pdf
- A good discussion can also be found in Groups, Physics, and Geometry by Gilmore

The motto in this section is: *the higher the level of abstraction, the better*.

- Common Question 1

- Common Question 2

- Example1

- Example2:

**Contributing authors:**

Jakob Schwichtenberg

advanced_tools/wigners_little_groups.txt · Last modified: 2017/12/04 07:01 (external edit)