Gamma matrices and projection operator question on different representations

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Projection operators for chirality are defined as P_- = 1/2(1 - γ^5) and P_+ = 1/2(1 + γ^5), with γ^5 being expressed as iγ^0γ^1γ^2γ^3. In different representations, these operators can appear less straightforward, leading to challenges in identifying the chirality of spinors. The left-handed and right-handed spinors may mix in some representations, but they can still be characterized by their eigenvalues relative to the projection operators. The chiral basis is determined by the eigenvectors of these operators, which may not always conform to simple forms like (1,0). For further reading, Srednicki's QFT book is recommended for a comprehensive understanding of Clifford algebra and its representations.
choongstring
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Typically I understand that projection operators are defined as

P_-=\frac{1}{2}(1-\gamma^5)
P_+=\frac{1}{2}(1+\gamma^5)

where typically also the fifth gamma matrices are defined as

\gamma^5=i\gamma^0\gamma^1\gamma^2\gamma^3

and.. as we choose different representations the projection operators are.. sometimes in nice form where there is only one identity element however what happens when in certain representations it doesn't come out nicely like that how do I interpret which type of spinors are which chiraliity and such. .. anyways and what are some good materials. (shorter the better) on something complete on clifford algebra and it's representations and all the other things like charge conjugation and such.
 
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choongstring said:
Typically I understand that projection operators are defined as

P_-=\frac{1}{2}(1-\gamma^5)
P_+=\frac{1}{2}(1+\gamma^5)

where typically also the fifth gamma matrices are defined as

\gamma^5=i\gamma^0\gamma^1\gamma^2\gamma^3

and.. as we choose different representations the projection operators are.. sometimes in nice form where there is only one identity element however what happens when in certain representations it doesn't come out nicely like that how do I interpret which type of spinors are which chiraliity and such. .. anyways and what are some good materials. (shorter the better) on something complete on clifford algebra and it's representations and all the other things like charge conjugation and such.

It's just that in other representations the left-handed and right-handed spinors are mixed. It's super clear if you use the two-component notation. For references you can read Srednicki's QFT book.
 
So even in other representations, left-handed and right-handed are defined as
(0,1) (1,0) kind of way? (although this is not a rigorous definition)
 
choongstring said:
So even in other representations, left-handed and right-handed are defined as
(0,1) (1,0) kind of way? (although this is not a rigorous definition)

In any representation, the chiral basis is defined as the eigenvector of the projection operator. So it won't always be like (1,0).
 

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