Dirac gammology - dimension of the algebra

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SUMMARY

The discussion focuses on the Dirac matrices, specifically their algebraic properties in 3+1 dimensions, which confirm that the dimension of this algebra is 4. The relation \gamma^\mu\gamma^\nu+\gamma^\nu\gamma^\mu=2g^{\mu\nu} is central to understanding this dimension. It is established that any set of four 4x4 matrices, such as {\gamma^0,\gamma^1,\gamma^2,\gamma^3}, forms a complete basis, and the existence of 12 additional linearly independent matrices further supports this conclusion. The dimension of representation is derived from the theorems of Schur and Frobenius.

PREREQUISITES
  • Understanding of Dirac matrices and their properties
  • Familiarity with linear algebra concepts, particularly linear independence
  • Knowledge of the metric tensor in the context of spacetime
  • Basic grasp of representation theory, including Schur and Frobenius theorems
NEXT STEPS
  • Study the properties of Dirac matrices in quantum mechanics
  • Explore linear algebra techniques for proving linear independence
  • Research the metric tensor and its implications in 3+1 dimensional spacetime
  • Investigate representation theory, focusing on Schur and Frobenius theorems
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The discussion is beneficial for physicists, mathematicians, and students studying quantum mechanics or advanced linear algebra, particularly those interested in the algebraic structures of Dirac matrices and their applications in theoretical physics.

Loro
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Dirac matrices satisfy the relations:

\gamma^\mu\gamma^\nu+\gamma^\nu\gamma^\mu=2g^{\mu\nu}

I would like to understand why the dimension of this algebra in 3+1 dimensions is 4.

If we're looking for all possible sets {\gamma^0,\gamma^1,\gamma^2,\gamma^3} of 4x4 matrices that satisfy this, how do I show that when I find just one set, it already forms a complete basis?
 
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You know that there are 4 matrices to begin with (the nr of matrices is equal to the dimension of space-time, i.e 4).. You need to show they are 4*4 and not 3*3, 5*5, 6*6, etc. You can show that starting with these 4, there are 12 more linear independent matrices. Then the dimension of representation follows from the theorem of Schur and Frobenius.
 
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